Netowrk Working Group H. Lu
Request for Comments: 2458 Editor
Category: Informational M. Krishnaswamy
Lucent Technologies
L. Conroy
Roke Manor Research
S. Bellovin
F. Burg
A. DeSimone
K. Tewani
AT&T Labs
P. Davidson
Nortel
H. Schulzrinne
Columbia University
K. Vishwanathan
Isochrome
November 1998
Netowrk Working Group H. Lu
Request for Comments: 2458 Editor
Category: Informational M. Krishnaswamy
Lucent Technologies
L. Conroy
Roke Manor Research
S. Bellovin
F. Burg
A. DeSimone
K. Tewani
AT&T Labs
P. Davidson
Nortel
H. Schulzrinne
Columbia University
K. Vishwanathan
Isochrome
November 1998
Toward the PSTN/Internet Inter-Networking --Pre-PINT Implementations
走向PSTN/互联网互联——PINT前的实现
Status of this Memo
本备忘录的状况
This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
本备忘录为互联网社区提供信息。它没有规定任何类型的互联网标准。本备忘录的分发不受限制。
Copyright Notice
版权公告
Copyright (C) The Internet Society (1998). All Rights Reserved.
版权所有（C）互联网协会（1998年）。版权所有。
Abstract
摘要
This document contains the information relevant to the development of the inter-networking interfaces underway in the Public Switched Telephone Network (PSTN)/Internet Inter-Networking (PINT) Working Group. It addresses technologies, architectures, and several (but by no means all) existing pre-PINT implementations of the arrangements through which Internet applications can request and enrich PSTN telecommunications services. The common denominator of the enriched services (a.k.a. PINT services) is that they combine the Internet and PSTN services in such a way that the Internet is used for non-voice interactions, while the voice (and fax) are carried entirely over the PSTN. One key observation is that the pre-PINT implementations, being developed independently, do not inter-operate. It is a task of the PINT Working Group to define the inter-networking interfaces that
本文件包含公共交换电话网（PSTN）/互联网互联（PINT）工作组正在进行的互联接口开发相关信息。它涉及技术、体系结构和一些（但并非全部）现有的协议前实现，通过这些协议，互联网应用程序可以请求和丰富PSTN电信服务。丰富服务（又称PINT服务）的共同点是，它们将互联网和PSTN服务结合在一起，使互联网用于非语音交互，而语音（和传真）完全通过PSTN传输。一个关键的观察结果是，独立开发的pre-PINT实现不会相互操作。PINT工作组的任务是定义所需的网络间接口
will support inter-operation of the future implementations of PINT services.
将支持PINT服务未来实现的互操作。
Table of Contents
目录
1. Introduction ....................................... 3
2. Terminology ....................................... 3
3. PINT Services ....................................... 4
4. Architectural Overview ............................... 5
4.1 Public Switched Telephone Network ............... 5
4.2 Pre-PINT Systems ............................... 9
5. IN-Based Solutions ............................... 20
5.1 The Lucent System ............................... 20
5.1.1 Roles of the Web Server, Service Node, and SMS ....... 20
5.1.2 A Click-to-Dial-Back Service Scenario ............... 21
5.1.3 Web Server-Service Node Interface ............... 22
5.1.4 Web Server-SMS Interface and SNMP MIB ............... 24
5.1.5 Security Considerations ........................... 26
5.2 Siemens Web Call Center ........................... 27
5.2.1 Service Description ............................... 27
5.2.2 Implementation ................................... 29
5.2.3 Derived Requirements/Lessons ..................... 35
6. Alternative Solutions ............................... 37
6.1 The AT&T System ..................................... 37
6.1.1 High Level Architecture ............................ 38
6.1.2 IP Client to CallBroker Interface .................. 39
6.1.3 Protocol ........................................... 40
6.1.4 APIs Exposed to the IP Client ..................... 41
6.1.5 Voice-Bridge Control API ........................ 41
6.2 Simple Computer Telephony Protocol ............... 41
6.2.1 Overview ........................................... 41
6.2.2 How SCTP Fits in with the Reference PINT Services .. 42
7. Session Initiation Protocol--An Emerging Standard .. 43
7.1 Overview ....................................... 43
7.2 SIP Protocol ....................................... 44
7.3 SIP Entities ....................................... 45
7.4 Providing Call Control Functionality ............... 46
8. Overall Security Considerations ..................... 47
9. Conclusion ....................................... 48
10. Acknowledgments ................................... 48
11. Appendix ....................................... 49
11.1 PSTN/IN 101 ....................................... 49
11.1.1 Public Switched Telephone Network ............... 49
11.1.2 Intelligent Network ............................... 51
11.2 Call Center Features ............................. 54
1. Introduction ....................................... 3
2. Terminology ....................................... 3
3. PINT Services ....................................... 4
4. Architectural Overview ............................... 5
4.1 Public Switched Telephone Network ............... 5
4.2 Pre-PINT Systems ............................... 9
5. IN-Based Solutions ............................... 20
5.1 The Lucent System ............................... 20
5.1.1 Roles of the Web Server, Service Node, and SMS ....... 20
5.1.2 A Click-to-Dial-Back Service Scenario ............... 21
5.1.3 Web Server-Service Node Interface ............... 22
5.1.4 Web Server-SMS Interface and SNMP MIB ............... 24
5.1.5 Security Considerations ........................... 26
5.2 Siemens Web Call Center ........................... 27
5.2.1 Service Description ............................... 27
5.2.2 Implementation ................................... 29
5.2.3 Derived Requirements/Lessons ..................... 35
6. Alternative Solutions ............................... 37
6.1 The AT&T System ..................................... 37
6.1.1 High Level Architecture ............................ 38
6.1.2 IP Client to CallBroker Interface .................. 39
6.1.3 Protocol ........................................... 40
6.1.4 APIs Exposed to the IP Client ..................... 41
6.1.5 Voice-Bridge Control API ........................ 41
6.2 Simple Computer Telephony Protocol ............... 41
6.2.1 Overview ........................................... 41
6.2.2 How SCTP Fits in with the Reference PINT Services .. 42
7. Session Initiation Protocol--An Emerging Standard .. 43
7.1 Overview ....................................... 43
7.2 SIP Protocol ....................................... 44
7.3 SIP Entities ....................................... 45
7.4 Providing Call Control Functionality ............... 46
8. Overall Security Considerations ..................... 47
9. Conclusion ....................................... 48
10. Acknowledgments ................................... 48
11. Appendix ....................................... 49
11.1 PSTN/IN 101 ....................................... 49
11.1.1 Public Switched Telephone Network ............... 49
11.1.2 Intelligent Network ............................... 51
11.2 Call Center Features ............................. 54
12. References ....................................... 56
Authors' Addresses ......................................... 57
Full Copyright Statement .................................. 60
12. References ....................................... 56
Authors' Addresses ......................................... 57
Full Copyright Statement .................................. 60
This document contains the information relevant to the development of the inter-networking interfaces underway in the Public Switched Telephone Network (PSTN)/Internet Inter-Networking (PINT) Working Group. It addresses technologies, architectures, and several (but by no means all) existing pre-PINT implementations of the arrangements through which Internet applications can request and enrich PSTN telecommunications services. The common denominator of the enriched services (a.k.a. PINT services) is that they combine the Internet and PSTN services in such a way that the Internet is used for non-voice interactions, while the voice (and fax) are carried entirely over the PSTN.
本文件包含公共交换电话网（PSTN）/互联网互联（PINT）工作组正在进行的互联接口开发相关信息。它涉及技术、体系结构和一些（但并非全部）现有的协议前实现，通过这些协议，互联网应用程序可以请求和丰富PSTN电信服务。丰富服务（又称PINT服务）的共同点是，它们将互联网和PSTN服务结合在一起，使互联网用于非语音交互，而语音（和传真）完全通过PSTN传输。
The organization of the document is as follows. First, the basic terminology and a short "intuitive" description of the PINT services are provided. The rest of the information deals, in one way or the other, with the pre-PINT support of these services where they are used as a benchmark. Thus, an architectural overview common to all present solutions is presented. The flow of the document then divides into two streams: one is dedicated to the Intelligent Network (IN)-based solutions; the other explores alternative means (i.e., CallBroker and Computer-Telephony Integration (CTI) approach). At this point, the emerging standards are explored, in particular, the Session Initiation Protocol (SIP), which promises an elegant solution to the PINT problem. Each of the above developments is addressed in a respective section. The final sections of the document contain the overall security considerations, conclusion, acknowledgments, appendix, and a set of references. The security section summarizes the PINT security requirements derived from the pre-PINT experiences and the appendix presents a tutorial on the PSTN, IN, and Call Center functions.
本文件的组织结构如下。首先，提供了PINT服务的基本术语和简短的“直观”描述。其余的信息以这样或那样的方式与这些服务的pre-PINT支持进行交易，这些服务被用作基准。因此，本文给出了所有现有解决方案共有的体系结构概述。然后，文档流分为两个流：一个流专门用于基于智能网络（IN）的解决方案；另一种是探索替代方法（即CallBroker和计算机电话集成（CTI）方法）。在这一点上，我们将探讨新出现的标准，特别是会话启动协议（SIP），它承诺为PINT问题提供一个优雅的解决方案。上述每一项发展都在各自的章节中进行了阐述。文档的最后部分包含总体安全考虑、结论、确认、附录和一组参考资料。安全部分总结了PINT之前的经验得出的PINT安全要求，附录介绍了PSTN、IN和呼叫中心功能的教程。
This document uses the following terminology:
本文件使用以下术语：
Authentication -- verification of the identity of a party.
身份验证——验证一方的身份。
Authorization -- determination of whether or not a party has the right to perform certain activities.
授权——确定一方是否有权进行某些活动。
PINT Gateway -- the PSTN node that interacts with the Internet.
PINT网关——与Internet交互的PSTN节点。
User or Customer -- the person who asks for a service request to be issued. In the context of PINT Services, this person will use an Internet host to make his or her request. The term "user" is also used to describe a host originating the PINT service request on behalf of this person.
用户或客户——请求发出服务请求的人。在PINT服务的上下文中，此人将使用Internet主机发出请求。术语“用户”还用于描述代表此人发起PINT服务请求的主机。
This document addresses four services initially identified by the PINT Working Group and presently supported by pre-PINT implementations. These services are: click-to-dial-back, click-to-fax, click-to-fax-back and voice-access-to-content.
本文档介绍了PINT工作组最初确定的四项服务，目前由PINT之前的实现提供支持。这些服务包括：单击以回拨、单击以传真、单击以回传真和语音访问内容。
Note that the word "click" should not be taken literally. It is rather used to point out that initiation of the related services takes place on the Internet, where point and click are the most prevalent user actions. In other words, a service request could originate from any type of IP-based platforms. There is no implication that these services must be implemented by a device within the PSTN or the Internet running a Web server.
请注意，“点击”一词不应按字面理解。它更倾向于指出，相关服务的启动发生在互联网上，点击是最普遍的用户行为。换句话说，服务请求可以来自任何类型的基于IP的平台。这并不意味着这些服务必须由PSTN或运行Web服务器的Internet内的设备实现。
The common denominator of the PINT services is that they combine the Internet and PSTN services in such a way that the Internet is used for non-voice interactions, while the voice (and fax) are carried entirely over the PSTN. (An example of such a service is combination of a Web-based Yellow Pages service with the ability to initiate PSTN calls between customers and suppliers in a manner described in what follows.)
PINT服务的共同点是，它们将Internet和PSTN服务结合在一起，使Internet用于非语音交互，而语音（和传真）完全通过PSTN传输。（此类服务的一个示例是基于Web的黄页服务与以下所述方式在客户和供应商之间发起PSTN呼叫的能力的组合。）
Some of the benefits of using the PSTN are high quality of the voice, an ability to route the call to different locations depending on pre-set criteria (for example, time of the day, day of the week, and geographic location), outstanding security and reliability, and access to flexible, low cost, and secure billing and charging systems. The benefits of using the Internet are the uniform, well-defined, and widely-used interfaces available anywhere, anytime.
使用PSTN的一些好处是语音质量高，能够根据预设标准（例如，一天中的时间、一周中的某一天和地理位置）将呼叫路由到不同的位置，出色的安全性和可靠性，以及访问灵活、低成本、安全的计费和收费系统。使用互联网的好处是随时随地都可以使用统一、定义良好且广泛使用的接口。
Click-to-Dial-Back
单击以回拨
With this service, a user requests (through an IP host) that the PSTN call be established between another party and himself or herself. An important pre-requisite for using this service is that the user has simultaneous access to both the PSTN and Internet.
使用此服务，用户请求（通过IP主机）在另一方和自己之间建立PSTN呼叫。使用此服务的一个重要先决条件是用户可以同时访问PSTN和Internet。
One example of an application of this service is on-line shopping: a user browsing through an on-line catalogue, clicks a button thus inviting a call from a sales representative. Note that (as is the case with the all-PSTN Free-Phone, or "800", service) flexible
这项服务的一个应用实例是在线购物：用户浏览在线目录，点击按钮，从而邀请销售代表来电。请注意（与所有PSTN免费电话或“800”服务一样）灵活
billing arrangements can be implemented here on behalf of the service provider. In addition (and also similarly to the Free-Phone/800), the PSTN could route the call depending on the time of day, day of week, availability of agents in different locations, and so on.
可以代表服务提供商在此处执行计费安排。此外（也类似于免费电话/800），PSTN可以根据一天中的时间、一周中的哪一天、不同地点是否有代理等来路由呼叫。
Click-to-Fax
单击以传真
With this service, a user at an IP host requests that a fax be sent to a particular fax number. In particular this service is especially meaningful when the fax is to be sent to someone who has only a fax machine (but no access to the Internet). Consider, as an example, a service scenario in which a Web user makes a reservation for a hotel room in Beijing from a travel service page containing hotel information of major cities around the world. Suppose a specific Beijing hotel chosen by the user does not have Internet connection but has a fax machine. The user fills out the hotel reservation form and then clicks a button sending out the form to the travel service provider, which in turn generates a fax request and sends it together with the hotel reservation form to the PSTN. Upon receiving the request and the associated data, the PSTN translates the data into the proper facsimile format and delivers it to the Beijing hotel as specified in the fax request.
使用此服务，IP主机上的用户请求将传真发送到特定的传真号码。特别是，当传真发送给只有传真机（但无法访问互联网）的人时，这项服务尤其有意义。例如，考虑一个服务场景，其中Web用户从包含世界主要城市酒店信息的旅行服务页面中预订北京酒店房间。假设用户选择的特定北京酒店没有互联网连接，但有传真机。用户填写酒店预订表单，然后单击按钮将表单发送给旅行社提供商，旅行社提供商随后生成传真请求并将其与酒店预订表单一起发送到PSTN。在收到请求和相关数据后，PSTN将数据转换为正确的传真格式，并按照传真请求中的规定将其发送至北京酒店。
Click-to-Fax-Back
单击以传真回
With this service, a user at an IP host can request that a fax be sent to him or her. (Consider the user of the previous example, who now requests the confirmation from the Beijing Hotel. Another useful application of the service is when size of the information that a user intends to get is so large that downloading it to the user's PC over the Internet will require a long time and a lot of disk space.)
通过此服务，IP主机上的用户可以请求向其发送传真。（以上一个例子中的用户为例，他现在请求北京酒店确认。该服务的另一个有用应用是，当用户想要获取的信息太大，通过互联网下载到用户的PC上需要很长时间和大量磁盘空间时。）
Voice-Access-to-Content
对内容的语音访问
With this service, a user at an IP host requests that certain information on the Internet be accessed (and delivered) in an audio form over the PSTN, using the telephone as an informational appliance. One application of this service is to provide Web access to the blind. (This may require special resources--available in the PSTN--to convert the Web data into speech.)
通过此服务，IP主机上的用户请求通过PSTN以音频形式访问（和传送）Internet上的某些信息，并将电话用作信息设备。这项服务的一个应用是为盲人提供网络访问。（这可能需要PSTN中提供的特殊资源将Web数据转换为语音。）
From an application perspective, Internet nodes are interconnected directly, as shown in Figure 1. When two machines are to communicate, they will have the address of the destination end system, and will
从应用程序的角度来看，Internet节点直接互连，如图1所示。当两台机器要通信时，它们将具有目标端系统的地址，并且
send network level datagrams, assuming that the underlying infrastructure will deliver them as required.
发送网络级数据报，假设底层基础设施将根据需要提供这些数据报。
_____
__ _____/ \_____
[__] / \
[----]-.-.-.-. Internet .-.
\_____ _______/ |
__ \__./ __ .
[__] / [__] |
[----]-. [----]-.
_____
__ _____/ \_____
[__] / \
[----]-.-.-.-. Internet .-.
\_____ _______/ |
__ \__./ __ .
[__] / [__] |
[----]-. [----]-.
Key: .-.-. Internet Access Link
关键字：.-.-。互联网接入链路
Figure 1
图1
Where all nodes are on the same (broadcast) network, there is no need for intervening routers; they can send and deliver packets to one another directly. The Internet nodes are responsible for their own communications requests, and act as peers in the communication sessions that result.
如果所有节点都在同一（广播）网络上，则不需要介入路由器；它们可以直接互相发送和传递数据包。Internet节点负责其自己的通信请求，并在产生的通信会话中充当对等方。
This contrasts with the situation in the PSTN. There, the end systems are configured as shown in Figure 2. The end systems tend to be specific to a particular type of traffic, so that, for example, the majority of terminals are dedicated to carrying speech traffic (telephones) or to carrying facsimile data (fax machines). The terminals all connect to Central Offices (COs) via access lines, and these COs are interconnected into a network.
这与PSTN中的情况形成对比。在这里，终端系统的配置如图2所示。终端系统往往特定于特定类型的业务，因此，例如，大多数终端专用于承载语音业务（电话）或承载传真数据（传真机）。这些终端都通过接入线连接到中央办公室（COs），这些COs相互连接成一个网络。
/--\
()/\()__
/__\ \ .................................
\ ! ! ! /--\
__ \ [-!-] [-!-] ! ()/\()
\ \ \__[CO ]=========[CO ]==\\ ! ___/__\
[Fax]________[---] [---] \\ [-!-] / __
\\=======[CO ]____/ \ \
[---]________[Fax]
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
CO Central Office (Telephone Exchange)
/--\
()/\()__
/__\ \ .................................
\ ! ! ! /--\
__ \ [-!-] [-!-] ! ()/\()
\ \ \__[CO ]=========[CO ]==\\ ! ___/__\
[Fax]________[---] [---] \\ [-!-] / __
\\=======[CO ]____/ \ \
[---]________[Fax]
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
CO Central Office (Telephone Exchange)
Figure 2
图2
Communications between the terminals are all "circuit switched", so a dedicated synchronous data path (or circuit) needs to be placed between the end terminals for carrying all communications. Arranging for such a circuit to be made or removed (cleared) is the responsibility of the Central Offices in the network. A user makes a request via his or her terminal, and this request is passed on to the "local" Central Office. The relationship between the terminals and the local Central Offices to which they are connected is strictly Client/Server.
终端之间的通信都是“电路交换”的，因此需要在终端之间放置一条专用的同步数据路径（或电路），以承载所有通信。网络中的中央办公室负责安排修建或拆除（清除）此类线路。用户通过其终端发出请求，并将该请求传递到“本地”中央办公室。终端和它们所连接的本地中心办公室之间的关系严格是客户机/服务器关系。
The COs are interconnected using two different types of connections. One of these is called a trunk connection (shown as a double line in the above figure) and is used to carry the data traffic generated by the terminals. The other connection acts as part of a separate network (and is shown as a dotted line in the above figure). This is the signaling network, and is used by the Central Offices to request a connection to be made between themselves and the destination of the required circuit. This will be carried across the trunk link to the "next" Central Office in the path. The path, once in place through the PSTN, always takes the same route. This contrasts with the Internet, where the underlying datagram nature of the infrastructure means that data packets are carried over different routes, depending on the combined traffic flows through the network at the time.
COs使用两种不同类型的连接进行互连。其中之一称为中继连接（上图中显示为双线），用于承载终端生成的数据流量。另一个连接作为单独网络的一部分（在上图中显示为虚线）。这是信令网络，由中央办公室用于请求在其自身和所需电路的目的地之间建立连接。这将通过主干链路传送到路径中的“下一个”中央办公室。一旦通过PSTN，路径始终采用相同的路径。这与互联网形成了对比，互联网基础设施的底层数据报性质意味着数据包通过不同的路由传输，这取决于当时通过网络的组合流量。
The call set up process can be viewed as having two parts: one in which a request for connection is made, and the other in which the circuit is made across the PSTN and call data flows between the communicating parties. This is shown in the next pair of figures (3a and 3b).
呼叫建立过程可以被视为有两个部分：一个部分发出连接请求，另一个部分通过PSTN发出电路并在通信方之间进行呼叫数据流。这在下一对图（3a和3b）中显示。
/--\
() ()
--____
/++\ \
/----\ \
A \ [-!-]
\->[CO ]
[---]
Time = 13:55
/--\
() ()
--____
/++\ \
/----\ \
A \ [-!-]
\->[CO ]
[---]
Time = 13:55
Figure 3a
图3a
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
CO Central Office (Telephone Exchange)
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
CO Central Office (Telephone Exchange)
/--\
() ()
-- .................................
/ \<--- ^ ! ! /--\
/----\ \ ! v ! () ()
A' \ [-!-] [-!-] ! --
\__[CO ]=========[CO ]==\\ v ->-/ \
[---] [---] \\ [-!-] / /----\
\\=======[CO ]____/ B'
Time = 14:00 [---]
/--\
() ()
-- .................................
/ \<--- ^ ! ! /--\
/----\ \ ! v ! () ()
A' \ [-!-] [-!-] ! --
\__[CO ]=========[CO ]==\\ v ->-/ \
[---] [---] \\ [-!-] / /----\
\\=======[CO ]____/ B'
Time = 14:00 [---]
Figure 3b
图3b
Figure 3 shows a particular kind of service that can be provided; call booking. With this service, a request is sent for a connection to be made between the A and B telephones at a specified time. The telephone is then replaced (the request phase is terminated). At the specified time, the CO will make a connection across the network in the normal way, but will, first, ring the "local" or A' telephone to inform the user that his or her call is now about to be made.
图3显示了可以提供的特定类型的服务；电话预约。有了这项服务，就可以在指定的时间在a和B电话之间发送连接请求。然后更换电话（请求阶段终止）。在指定时间，CO将以正常方式通过网络进行连接，但首先会拨打“本地”或“a”电话，通知用户他或她的电话即将拨打。
For more complex services, the requesting telephone is often connected via its "local" CO to a Service Node (SN), where the user can be played prompts and can specify the parameters of his or her request in a more flexible manner. This is shown below, in Figures 4a and 4b. For more details of the operation of the Service Node (and other Intelligent Network units), see the Appendix.
对于更复杂的服务，请求电话通常通过其“本地”CO连接到服务节点（SN），在那里可以播放提示并以更灵活的方式指定用户请求的参数。下图4a和4b显示了这一点。有关服务节点（和其他智能网络单元）操作的更多详细信息，请参阅附录。
When the SN is involved in the request and in the call setup process, it appears, to the CO, to be another PSTN terminal. As such, the initial request is routed to the Service Node, which, as an end system, then makes two independent calls "out" to A' and B'.
当SN涉及请求和呼叫建立过程时，对CO来说，它似乎是另一个PSTN终端。因此，初始请求被路由到服务节点，服务节点作为终端系统，然后向A'和B'发出两个独立的“out”调用。
/--\ [---]
() () [SN ]
--___ [|--]
/++\ \ |
/----\ \ |
\ |
A \ [|-!]
\->[CO ]
[---]
Time = 13:55
/--\ [---]
() () [SN ]
--___ [|--]
/++\ \ |
/----\ \ |
\ |
A \ [|-!]
\->[CO ]
[---]
Time = 13:55
Figure 4a
图4a
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
CO Central Office (Telephone Exchange)
SN Service Node
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
CO Central Office (Telephone Exchange)
SN Service Node
/--\ [---]
() () [SN ]
-- [|--] /--\
/ \<-- | ............................... () ()
/----\ \ | ^ ! ! --
\ | / v v / \
A' \ [|-!] [-!-] [-!-] ->-/----\
\--[CO ] [CO ] [CO ] /
[---] [---] [---]___/ B'
Time = 14:00
/--\ [---]
() () [SN ]
-- [|--] /--\
/ \<-- | ............................... () ()
/----\ \ | ^ ! ! --
\ | / v v / \
A' \ [|-!] [-!-] [-!-] ->-/----\
\--[CO ] [CO ] [CO ] /
[---] [---] [---]___/ B'
Time = 14:00
Figure 4b
图4b
Note that in both cases as shown in Figures 3 and 4 a similar service can be provided in which the B' telephone is replaced by an Intelligent Peripheral (or an Special Resource Functional entity within a Service Node), playing an announcement. This allows a "wake up" call to be requested, with the Intelligent Peripheral or Service Node Special Resource playing a suitable message to telephone A' at the specified time. Again, for more details of the operation of the Special Resources (and other Intelligent Network units), see the Appendix.
请注意，在图3和图4所示的两种情况下，都可以提供类似的服务，其中B'电话由智能外围设备（或服务节点内的特殊资源功能实体）代替，播放公告。这允许请求“唤醒”呼叫，智能外围设备或服务节点专用资源在指定时间播放合适的消息给电话“a”。同样，有关特殊资源（和其他智能网络单元）运行的更多详细信息，请参见附录。
Although the pre-PINT systems reported here (i.e., those developed by AT&T, Lucent, Siemens and Nortel) vary in the details of their operation, they exhibit similarities in the architecture. This section highlights the common features. Specific descriptions of these systems will follow.
尽管此处报告的pre-PINT系统（即AT&T、朗讯、西门子和北电开发的系统）在操作细节上有所不同，但它们在架构上表现出相似性。本节重点介绍了常见功能。下面将对这些系统进行具体说明。
All of the systems can be seen as being quite similar to that shown in the following diagram. In each case, the service is separated into two parts; one for the request and another for execution of the service. Figure 5 summarizes the process.
所有系统都与下图所示非常相似。在每种情况下，服务分为两部分；一个用于请求，另一个用于执行服务。图5总结了该过程。
_____
__ _____/ \_____
[__] / \
[-++-]-.-.>.-. Internet .-.-
\_____ _______/ .
\___/ v
[----] .
[PINT]-.-
[----]
%
v
[---]
[SN ]
[|--]
_____
__ _____/ \_____
[__] / \
[-++-]-.-.>.-. Internet .-.-
\_____ _______/ .
\___/ v
[----] .
[PINT]-.-
[----]
%
v
[---]
[SN ]
[|--]
Figure 5a
图5a
Key: CO Central Office (Telephone Exchange)
SN Service Node
PINT PSTN/Internet Gateway
.-.-. Internet Access Link
%%% Gateway/Service Node Link
___ PSTN Access Lines
=== PSTN Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
Key: CO Central Office (Telephone Exchange)
SN Service Node
PINT PSTN/Internet Gateway
.-.-. Internet Access Link
%%% Gateway/Service Node Link
___ PSTN Access Lines
=== PSTN Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
_____
__ _____/ \_____
[__] / \
[----]-.-.-.-. Internet .-.-
\_____ _______/ .
\___/ |
[----] .
[PINT]-.-
[-%--]
%
%
/--\ [-%-]
() () [SN ]
-- [|--] /--\
/ \<-- | .................... () ()
/----\ \ | ^ ! ! --
\ | / v v / \
A' \ [|-!] [-!-] [-!-] ->-/----\
\--[CO ]=======[CO ]======[CO ] /
[---] [---] [---]__/ B'
_____
__ _____/ \_____
[__] / \
[----]-.-.-.-. Internet .-.-
\_____ _______/ .
\___/ |
[----] .
[PINT]-.-
[-%--]
%
%
/--\ [-%-]
() () [SN ]
-- [|--] /--\
/ \<-- | .................... () ()
/----\ \ | ^ ! ! --
\ | / v v / \
A' \ [|-!] [-!-] [-!-] ->-/----\
\--[CO ]=======[CO ]======[CO ] /
[---] [---] [---]__/ B'
Figure 5b
图5b
Comparing Figure 4a with Figure 5a, the differences lie in the way that the information specifying the request is delivered to the Service Node. In the PSTN/IN method shown in the earlier diagram, the user connects to the SN from the telephone labeled A, with the connection being routed via the CO. In the latter case, the request is delivered from an Internet node, via the PINT gateway, and thence to the Service Node over a "private" link. The effect is identical, in that the request for service is specified (although the actual parameters used to specify the service required may differ somewhat).
比较图4a和图5a，区别在于指定请求的信息被传递到服务节点的方式。在上图所示的PSTN/In方法中，用户从标有A的电话连接到SN，连接通过CO路由。在后一种情况下，请求通过PINT网关从Internet节点发送，然后通过“专用”链路发送到服务节点。其效果是相同的，因为指定了服务请求（尽管用于指定所需服务的实际参数可能有所不同）。
The figures depicting the respective service execution phases (Figures 4b and 5b) show that the operation, from the IN/PSTN perspective, is again identical. The Service Node appears to initiate two independent calls "out" to telephones A' and B'.
描绘各个服务执行阶段的图（图4b和5b）表明，从IN/PSTN的角度来看，该操作再次是相同的。服务节点似乎发起了两个独立的呼叫“out”到电话A'和B'。
The alternative systems developed by AT&T and by Nortel allow another option to be used in which the PINT Gateway does not have to connect to the PSTN via a Service Node (or other Intelligent Network component), but can instead connect directly to Central Offices that support the actions requested by the gateway. In these alternatives, the commands are couched at a "lower level", specifying the call states required for the intended service connection rather than the service identifier and the addresses involved (leaving the Intelligent Network components to coordinate the details of the service call on the gateway's behalf). In this way the vocabulary of the commands is closer to that used to control Central Offices. The difference really lies in the language used for the services specification, and all systems can use the overall architecture depicted in Figure 5; the only question remains whether the Intelligent Network components are actually needed in these other approaches.
AT&T和北电开发的替代系统允许使用另一种选择，即PINT网关不必通过服务节点（或其他智能网络组件）连接到PSTN，而是可以直接连接到支持网关请求的操作的中央办公室。在这些备选方案中，命令以“较低级别”表达，指定预期服务连接所需的呼叫状态，而不是所涉及的服务标识符和地址（让智能网络组件代表网关协调服务呼叫的细节）。通过这种方式，命令的词汇更接近用于控制中央办公室的词汇。区别在于服务规范所使用的语言，所有系统都可以使用图5所示的总体架构；唯一的问题仍然是，在这些其他方法中是否确实需要智能网络组件。
The following diagram (Figure 6) shows the interface architecture involved in providing the kind of service mentioned above.
下图（图6）显示了提供上述服务所涉及的接口体系结构。
Internet __ __
Server [__] _______ [__]
[W3S-]-. ___/ .-.-.-[W3C-] Internet
_________________|/.-.-.-.-. \ Terminal
/ .. . \
| Internet / . \ |
\___________ . . . /
\/___|____\_________/
. . .
/ | \
(A) (B) (E)
. . .
_|_ _|_ _|_
[SN ]<-(D)--[SMS]--(H)->[SCP]
[|-|] --- [-!-]
/ \ !
(C) (I) ...........(F)...!.(G).
/ \ ! !
[--|] [|-!] [-!-]
[CO ] [MSC] [SSP]
[---] [---] \|/ [---]
/--\ | |____| | /--\
()/\() | | ()/\()
/--\___| 1 |___/--\
Fixed PSTN Terminal [] Fixed PSTN Terminal
Mobile Terminal
Internet __ __
Server [__] _______ [__]
[W3S-]-. ___/ .-.-.-[W3C-] Internet
_________________|/.-.-.-.-. \ Terminal
/ .. . \
| Internet / . \ |
\___________ . . . /
\/___|____\_________/
. . .
/ | \
(A) (B) (E)
. . .
_|_ _|_ _|_
[SN ]<-(D)--[SMS]--(H)->[SCP]
[|-|] --- [-!-]
/ \ !
(C) (I) ...........(F)...!.(G).
/ \ ! !
[--|] [|-!] [-!-]
[CO ] [MSC] [SSP]
[---] [---] \|/ [---]
/--\ | |____| | /--\
()/\() | | ()/\()
/--\___| 1 |___/--\
Fixed PSTN Terminal [] Fixed PSTN Terminal
Mobile Terminal
Key: W3S HTTP (Web) Server
W3C HTTP (Web) Client/Browser
CO Central Office (Telephone Exchange)
MSC Mobile Switching Center (Mobile Network Telephone
Exchange)
SN Service Node
SSP Service Switching Point
SCP Service Control Point
SMS Service Management System
.-.-. Internet relationship
___ PSTN Access relationship
... PSTN "core" signaling relationship
Key: W3S HTTP (Web) Server
W3C HTTP (Web) Client/Browser
CO Central Office (Telephone Exchange)
MSC Mobile Switching Center (Mobile Network Telephone
Exchange)
SN Service Node
SSP Service Switching Point
SCP Service Control Point
SMS Service Management System
.-.-. Internet relationship
___ PSTN Access relationship
... PSTN "core" signaling relationship
Figure 6
图6
The interfaces are:
接口包括：
A The interface over which Internet requests for service are delivered to the Service Node B The interface over which Service Management requests are sent from the Internet to the Service Management System C The interface over which the Service Node sends call control requests to a connected Central Office D The interface over which the Service Management System manages the Service Node E The interface over which Internet requests for service are delivered to the Service Control Point F The interface over which the Service Control Point sends service call control requests to the Mobile Switching Center G The interface over which the Service Control Point sends service control requests to the Service Switching Point H The interface over which the Service Management System manages the Service Control Point I The interface over which the Service Node sends service call control requests to the Mobile Switching Center
A将Internet服务请求传送到服务节点的接口B将服务管理请求从Internet发送到服务管理系统的接口C服务节点将呼叫控制请求发送到连接的中央办公室的接口D服务通过的接口管理系统管理服务节点E、服务控制点向移动交换中心发送服务呼叫控制请求的接口F、服务控制点向移动交换中心发送服务呼叫控制请求的接口G、服务控制点向移动交换中心发送服务控制请求的接口服务交换点H是服务管理系统管理服务控制点I的接口，服务节点通过该接口向移动交换中心发送服务呼叫控制请求
In practice, a number of the interfaces have very similar purposes to one another. The means by which these purposes are achieved differ, in that some of the interfaces (C and I) reflect access arrangements, whilst others (F and G) imply a "core" signaling relationship. However, it is possible to categorize them in terms of the "intent" of messages sent across the interfaces.
实际上，许多接口彼此的用途非常相似。实现这些目的的方式有所不同，其中一些接口（C和I）反映了接入安排，而其他接口（F和G）暗示了“核心”信令关系。但是，可以根据跨接口发送的消息的“意图”对它们进行分类。
For example, Interfaces A and E are similar; one of the main aims of PINT work is to ensure that they are the same. Similarly, Interfaces D and H imply similar actions and are likely to carry similar messages. Interfaces C, F, G, and I are all used to request that a call be initiated, albeit via access or core signaling relationships.
例如，接口A和E是相似的；品脱工作的主要目的之一是确保它们是相同的。类似地，接口D和H意味着类似的操作，并且可能携带类似的消息。接口C、F、G和I都用于请求发起呼叫，尽管是通过访问或核心信令关系。
The interfaces can also be viewed in terms of the kind of components that are involved and the bodies by which they are codified. Interfaces A, B, and E are all going to be realized as Internet Protocols. All of the others use existing protocols in the PSTN/IN. Traditionally, these have been codified by different groups, and this is likely to be the case in the PINT work.
还可以根据所涉及的组件类型和编码它们的主体来查看接口。接口A、B和E都将作为Internet协议实现。其他所有协议都使用PSTN/in中的现有协议。传统上，这些都是由不同的团体编纂的，这可能是品脱作品中的情况。
The general arrangements for the different systems are shown below (Figures 7, 8, 9, and 10). They differ in the details of their configurations, but the main tasks they perform are very similar, and so the overall operation is similar to the generic architecture shown in Figures 5 and 6.
不同系统的总体布置如下所示（图7、图8、图9和图10）。它们在配置细节上有所不同，但它们执行的主要任务非常相似，因此总体操作类似于图5和图6所示的通用体系结构。
Key for following diagrams:
下图的关键点：
Components:
组件：
W3C World Wide Web Client W3S World Wide Web Server WSA Web Server "Back End Program" Interface (CGI or Servlet interface) Srvlt Servlet "back end" program/objects FS Finger Server SCTPC Simple Computer Telephony Protocol Client SCTPS Simple Computer Telephony Protocol Server CBC CallBroker Client CBS CallBroker Server SSTPC Service Support Transport Protocol Client SSF Service Switching Function SCF Service Control Function SRF Special Resource Function CO Central Office/ Public Telephone Exchange SSP Service Switching Point SCP Service Control Point SR/I.IP Special Resource/ "Internet" Intelligent Peripheral SMS Service Management System INAPAd Intelligent Network Application Part Adaptor PktFlt Packet Filter (Firewall) SNMPAg Simple Network Management Protocol Agent
W3C万维网客户端W3C万维网服务器WSA Web服务器“后端程序”接口（CGI或Servlet接口）Srvlt Servlet“后端”程序/对象FS Finger服务器SCTPC简单计算机电话协议客户端SCTPS简单计算机电话协议服务器CBC CallBroker客户端CBS CallBroker服务器SSTPC服务支持传输协议客户端SSF服务交换功能SCF服务控制功能SRF特殊资源功能CO中央办公室/公用电话Exchange SSP服务交换点SCP服务控制点SR/I.IP特殊资源/“Internet”智能外围SMS服务管理系统INAPAd智能网络应用程序部分适配器PktFlt包过滤器（防火墙）SNMPAg简单网络管理协议代理
Protocols:
协议：
P0 HyperText Transfer Protocol P1 HTTP Server <-> "Back End Program" internal protocol P2 CallBroker Client <-> CallBroker Server protocol (AT&T system), or SCTP Client <-> Server protocol (Nortel system) P3 PINT User Agent <-> PINT Gateway protocol P4 Intra-Intelligent Network protocol (e.g., INAP) P5 Proprietary (INAP-based) Gateway-> I.IP protocol P6 Finger protocol P7 Digital Subscriber Signaling 1 protocol P8 Simple Network Management Protocol P9 SMS <-> Service Control Point/Service Node protocol
P0超文本传输协议P1 HTTP服务器<->“后端程序”内部协议P2 CallBroker客户端<->CallBroker服务器协议（AT&T系统）或SCTP客户端<->服务器协议（北电系统）P3 PINT用户代理<->PINT网关协议P4内部智能网络协议（例如，INAP）P5专有（基于INAP）网关->I.IP协议P6手指协议P7数字用户信令协议P8简单网络管理协议P9 SMS<->服务控制点/服务节点协议
_____ _______ _____
|[W3C]|----(p0)-->| [W3S] |<--(p0)----|[W3C]|
|[---]| | [WSA] | |[FS.]|
|-----| | ! | |[-!-]|
| (p1) | |--\--|
| ! | ^
| ! | (p6)
| ! | \
| (p1) | \
| ! | \
|[Srvlt]| \
|___!___| \
! \
(p3) \
Internet ! !
.+.+.+.+.+.+.+.+.+.+.+. v .+.+.+.+.+.+.+.+.+.+.+.+.+.!.+.+.+.+.+.
PSTN/IN _______________!_________________ ____!_____ __________
|I [PktFlt] I| |[PktFlt]| |[PktFlt]|
|N Gateway N| | ! | | ! |
|A ___________________________ A| | ! | | ! |
|P | | P| | ! | |[SNMPAg]|
-(p4)-- |A | <-(p4)-> [SCP] <-(p4)-> | A|-(p5)->|[SR/IIP]| | [SMS] |
\ |d | [-^-] | d| |[------]| | [-^-] |
\ |__| ! |__| |________| |___!____|
\ ! !
[-v-] !-----------------(p9)-----------------!
[SSP]
[---]
___| |______
| |
| /--\ | /--\
| ()/\() | ()/\()
|__/__\ |____/__\
_____ _______ _____
|[W3C]|----(p0)-->| [W3S] |<--(p0)----|[W3C]|
|[---]| | [WSA] | |[FS.]|
|-----| | ! | |[-!-]|
| (p1) | |--\--|
| ! | ^
| ! | (p6)
| ! | \
| (p1) | \
| ! | \
|[Srvlt]| \
|___!___| \
! \
(p3) \
Internet ! !
.+.+.+.+.+.+.+.+.+.+.+. v .+.+.+.+.+.+.+.+.+.+.+.+.+.!.+.+.+.+.+.
PSTN/IN _______________!_________________ ____!_____ __________
|I [PktFlt] I| |[PktFlt]| |[PktFlt]|
|N Gateway N| | ! | | ! |
|A ___________________________ A| | ! | | ! |
|P | | P| | ! | |[SNMPAg]|
-(p4)-- |A | <-(p4)-> [SCP] <-(p4)-> | A|-(p5)->|[SR/IIP]| | [SMS] |
\ |d | [-^-] | d| |[------]| | [-^-] |
\ |__| ! |__| |________| |___!____|
\ ! !
[-v-] !-----------------(p9)-----------------!
[SSP]
[---]
___| |______
| |
| /--\ | /--\
| ()/\() | ()/\()
|__/__\ |____/__\
Figure 7: The Siemens Web Call Center
图7：西门子网络呼叫中心
_____ _______
|[W3C]|----(p0)-->| [W3S] |
|[---]| | [WSA] |
|-----| | ! |
| (p1) |
| ! |
| ! |
| ! |
| (p1) |
| ! |
|[SSTPC]|-<----------------------------------
|___!___| !
! (p8)
(p3) !
Internet ! v
.+.+.+.+.+.+.+.+.+.+.+. v .+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+. ! .+.+
PSTN/IN _______________!__________________________________ ____!_____
| [PktFlt] Service [PktFlt]| |[PktFlt]|
| ! Node | | ! |
| [SCF Adaptor] | | ! |
| ! | |[SNMPAg]|
|[SSF]<-(p4)->[SCF] <-------(p4)--------> [SRF] | | [SMS] |
|[|--] [-^-] [---] | | [-^-] |
|_|_____________!________________________________| |___!____|
| ! !
[-v-] (p7) !-----------------(p9)-----------------!
[CO.]____|
[---]
___| |_______
| |
| /--\ | /--\
| ()/\() | ()/\()
|__/__\ |____/__\
_____ _______
|[W3C]|----(p0)-->| [W3S] |
|[---]| | [WSA] |
|-----| | ! |
| (p1) |
| ! |
| ! |
| ! |
| (p1) |
| ! |
|[SSTPC]|-<----------------------------------
|___!___| !
! (p8)
(p3) !
Internet ! v
.+.+.+.+.+.+.+.+.+.+.+. v .+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+. ! .+.+
PSTN/IN _______________!__________________________________ ____!_____
| [PktFlt] Service [PktFlt]| |[PktFlt]|
| ! Node | | ! |
| [SCF Adaptor] | | ! |
| ! | |[SNMPAg]|
|[SSF]<-(p4)->[SCF] <-------(p4)--------> [SRF] | | [SMS] |
|[|--] [-^-] [---] | | [-^-] |
|_|_____________!________________________________| |___!____|
| ! !
[-v-] (p7) !-----------------(p9)-----------------!
[CO.]____|
[---]
___| |_______
| |
| /--\ | /--\
| ()/\() | ()/\()
|__/__\ |____/__\
Figure 8: The Lucent System
图8：朗讯系统
_____ ________
|[W3C]|----(p0)-->| [W3S] |
|[---]| | [WSA] |
|-----| | ! |
| (p1) |
| ! |
|[WS/CBS]|
|[Adaptr]|
|___!____|
^
(p2)
_____ ___v____
|[CBC]| | [CBS] |
|[---]|<---(p2)-->| [---] |-<---------------------------------
|-----| |___!____| !
! (p8)
(p3) !
Internet ! v
.+.+.+.+.+.+.+.+.+.+.+. v .+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+. ! .+.+
PSTN/IN _______________!__________________________________ ____!_____
| [PktFlt] Service [PktFlt]| |[PktFlt]|
| ! Node | | ! |
| [SCF Adaptor] | | ! |
| ! | |[SNMPAg]|
|[SSF]<-(p4)->[SCF] <-------(p4)--------> [SRF] | | [SMS] |
|[|--] [-^-] [---] | | [-^-] |
|_|_____________!________________________________| |___!____|
| ! !
[---] (p7) !-----------------(p9)-----------------!
[CO.]____|
[---]
___| |_______
| |
| /--\ | /--\
| ()/\() | ()/\()
|__/__\ |____/__\
_____ ________
|[W3C]|----(p0)-->| [W3S] |
|[---]| | [WSA] |
|-----| | ! |
| (p1) |
| ! |
|[WS/CBS]|
|[Adaptr]|
|___!____|
^
(p2)
_____ ___v____
|[CBC]| | [CBS] |
|[---]|<---(p2)-->| [---] |-<---------------------------------
|-----| |___!____| !
! (p8)
(p3) !
Internet ! v
.+.+.+.+.+.+.+.+.+.+.+. v .+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+. ! .+.+
PSTN/IN _______________!__________________________________ ____!_____
| [PktFlt] Service [PktFlt]| |[PktFlt]|
| ! Node | | ! |
| [SCF Adaptor] | | ! |
| ! | |[SNMPAg]|
|[SSF]<-(p4)->[SCF] <-------(p4)--------> [SRF] | | [SMS] |
|[|--] [-^-] [---] | | [-^-] |
|_|_____________!________________________________| |___!____|
| ! !
[---] (p7) !-----------------(p9)-----------------!
[CO.]____|
[---]
___| |_______
| |
| /--\ | /--\
| ()/\() | ()/\()
|__/__\ |____/__\
Figure 9: The AT&T System
图9:AT&T系统
_____ ________
|[W3C]|----(p0)-->| [W3S] |
|[---]| | [WSA] |
|-----| | ! |
| (p1) |
| ! |
|[WS/ ]|
|[ SCTPS]|
|[Adaptr]|
|___!____|
^
(p2)
_______ ___v___
|[SCTPC]| |[SCTPS]|
|[-----]| <-(p2)--> |[-----]|-<----------------------------------
|-------| |___!___| !
! (p8)
(p3) !
Internet ! v
.+.+.+.+.+.+.+.+.+.+.+. v .+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+. ! .+.+.
PSTN/IN _______________!__________________________________ ____!_____
| [PktFlt] Service [PktFlt]| |[PktFlt]|
| ! Node | | ! |
| [SCF Adaptor] | | ! |
| ! | |[SNMPAg]|
|[SSF]<-(p4)->[SCF] <-------(p4)--------> [SRF] | | [SMS] |
|[|--] [-^-] [---] | | [-^-] |
|_|_____________!________________________________| |___!____|
| ! !
[---] (p7) !-----------------(p9)-----------------!
[CO.]____|
[---]
___| |_______
| |
| /--\ | /--\
| ()/\() | ()/\()
|__/__\ |____/__\
_____ ________
|[W3C]|----(p0)-->| [W3S] |
|[---]| | [WSA] |
|-----| | ! |
| (p1) |
| ! |
|[WS/ ]|
|[ SCTPS]|
|[Adaptr]|
|___!____|
^
(p2)
_______ ___v___
|[SCTPC]| |[SCTPS]|
|[-----]| <-(p2)--> |[-----]|-<----------------------------------
|-------| |___!___| !
! (p8)
(p3) !
Internet ! v
.+.+.+.+.+.+.+.+.+.+.+. v .+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+.+. ! .+.+.
PSTN/IN _______________!__________________________________ ____!_____
| [PktFlt] Service [PktFlt]| |[PktFlt]|
| ! Node | | ! |
| [SCF Adaptor] | | ! |
| ! | |[SNMPAg]|
|[SSF]<-(p4)->[SCF] <-------(p4)--------> [SRF] | | [SMS] |
|[|--] [-^-] [---] | | [-^-] |
|_|_____________!________________________________| |___!____|
| ! !
[---] (p7) !-----------------(p9)-----------------!
[CO.]____|
[---]
___| |_______
| |
| /--\ | /--\
| ()/\() | ()/\()
|__/__\ |____/__\
Figure 10: The Nortel System
图10：北电系统
As these are independent systems developed by different groups, the names of the components, unsurprisingly, don't match. Some features are offered by one of the systems, while they aren't by others. However, there are a number of common features. All of the systems provide a Web-based interface (at least as an option), using "back end" programs to construct protocols to pass onwards to the Intelligent Network system.
由于这些系统是由不同的团队开发的独立系统，因此组件的名称不匹配也就不足为奇了。某些功能由其中一个系统提供，而其他系统不提供。然而，有一些共同的特点。所有系统都提供一个基于Web的接口（至少作为一个选项），使用“后端”程序来构建协议，以传递给智能网络系统。
Several Intelligent Network Functional Entities are combined into a Service Node in the Lucent, AT&T , and Nortel systems, while in the Siemens scheme they are separate units. However, this is not particularly important for the provision of the services they offer.
在朗讯、AT&T和北电系统中，若干智能网络功能实体被合并为一个服务节点，而在西门子方案中，它们是独立的单元。然而，这对于他们提供的服务来说并不特别重要。
The main difference lies in whether or not the SCF is "aware" of the Internet interface and has been modified to be "complicit" in supporting these Internet requests. The Siemens approach was to re-use an existing SCP, providing a gateway function to translate as needed. The Lucent system used a "lighter weight" SCF adapter to terminate the Internet protocols, as the SCF was modified to support the Internet interface directly.
主要区别在于SCF是否“意识到”互联网接口，并被修改为“共谋”支持这些互联网请求。西门子的方法是重新使用现有的SCP，根据需要提供翻译网关功能。朗讯系统使用了一个“重量更轻”的SCF适配器来终止互联网协议，因为SCF被修改为直接支持互联网接口。
The AT&T CallBroker and Nortel SCTP Servers introduce an intermediate protocol (labeled p2) that allows an alternative to the Web based interface supported by the others. This protocol matches the "CallBroker Client API", or the "SCTP Client API". These options provide for a bi-directional protocol, with indications sent from the Call Broker or SCTP Server to the Client as needed. This is not easily possible using an HTTP-based scheme (and in the Siemens case, a dedicated Finger client/server pair was used to emulate such an interface)
AT&T CallBroker和Nortel SCTP服务器引入了一个中间协议（标记为p2），允许替代其他服务器支持的基于Web的接口。此协议与“CallBroker客户端API”或“SCTP客户端API”匹配。这些选项提供双向协议，根据需要从呼叫代理或SCTP服务器向客户端发送指示。使用基于HTTP的方案很难做到这一点（在西门子的案例中，使用专用的Finger客户端/服务器对来模拟这种接口）
The protocol between the Internet server and the Intelligent Network (labeled p3 in the above diagrams) differs in each of the systems. One of the main aims of future work will be to develop a common protocol that will support the services offered, so that the p3 interface will allow different implementations to inter-operate. In the Lucent, Siemens, and Nortel systems, this was an "internal" protocol, as it was carried between entities within the Service Node or Gateway.
互联网服务器和智能网络（上图中标记为p3）之间的协议在每个系统中都不同。未来工作的主要目标之一是开发一个支持所提供服务的通用协议，以便p3接口允许不同的实现相互操作。在朗讯、西门子和北电系统中，这是一个“内部”协议，因为它在服务节点或网关内的实体之间传输。
Other contrasts between the systems lie in the support for Internet access to Service Management, and access to the Internet by Special Resources. Internet Management access was most developed in the Lucent system, in which a Simple Network Management Protocol (SNMP) agent was provided to allow inter-operation with the SMS controlling the Service Node. In the Siemens scheme, the SMS had no direct Internet access; any management actions were carried out within the normal PSTN management activities. As for Internet access to special resources, this was only required by the Siemens system as part of its support for Call Center agent notification. Equivalent functionality would be provided in the AT&T and Nortel systems as mentioned above, and this would in turn be associated with event notifications being sent as part of their (p3) Internet/IN protocol. These differences reflect the different emphases in the products as they were developed; again, future work will have to ensure that common protocols can be used to support the chosen services fully.
这些系统之间的其他差异在于支持互联网接入服务管理，以及通过特殊资源接入互联网。互联网管理访问在朗讯系统中开发得最多，该系统提供了一个简单网络管理协议（SNMP）代理，允许与控制服务节点的SMS进行交互操作。在西门子方案中，SMS没有直接的互联网接入；任何管理行动都是在正常的PSTN管理活动中执行的。至于对特殊资源的互联网访问，西门子系统仅要求这样做，作为其支持呼叫中心代理通知的一部分。如上所述，AT&T和Nortel系统将提供同等功能，这反过来又与作为其（p3）互联网/接入协议一部分发送的事件通知相关。这些差异反映了产品开发过程中的不同侧重点；同样，未来的工作将必须确保可以使用公共协议来充分支持所选择的服务。
Figure 11 depicts the overall interconnection architecture of the Lucent prototype in support of the four PINT services. The IN-based architecture utilizes the Service Node and Service Management System in addition to the Web server, which enables Web-based access to the PINT services. This section summarizes the roles of these elements (complemented by a click-to-dial-back service scenario), outlines the interfaces of Web Server-Service Node and Web Server-Service Management System (i.e., the interfaces A & B), and addresses the common security concerns.
图11描述了朗讯原型支持四品脱服务的整体互连架构。基于IN的体系结构除了Web服务器之外，还利用服务节点和服务管理系统，从而实现对PINT服务的基于Web的访问。本节总结了这些元素的作用（由点击回拨服务场景补充），概述了Web服务器服务节点和Web服务器服务管理系统的接口（即接口a和B），并解决了常见的安全问题。
5.1.1 Roles of the Web Server, Service Node, and Service Management System
5.1.1 Web服务器、服务节点和服务管理系统的角色
Web Server
网络服务器
The Web Server stores the profiles of content providers as well as pre-registered users. The content provider profile contains information such as content provider ID, telephone number, and fax number. In addition, the profile may also include service logic that specifies, for example, the telephone (or fax) number to be reached based on time of the day, day of the week, or geographical location of the user, and the conditions to accept the charge of the calls.
Web服务器存储内容提供商以及预注册用户的配置文件。内容提供商配置文件包含内容提供商ID、电话号码和传真号码等信息。此外，简档还可以包括服务逻辑，该服务逻辑指定例如基于一天中的时间、一周中的某一天或用户的地理位置、以及接受呼叫费用的条件而要达到的电话（或传真）号码。
Similar to the content provider profile, the pre-registered user profile contains information such as user name, password, telephone number, and fax number. The last two pieces of information can also be linked to time of the day and day of the week so the user can be reached at the appropriate telephone (or fax) number accordingly.
与内容提供商配置文件类似，预注册的用户配置文件包含用户名、密码、电话号码和传真号码等信息。最后两条信息还可以链接到一天中的时间和一周中的某一天，这样就可以通过相应的电话（或传真）号码联系到用户。
Service Node
服务节点
Situated in the PSTN, the SN, like the SCP, performs the service control function [1, 2, 3]. It executes service logic and instructs switches on how to complete a call. The SN also performs certain switching functions (like bridging of calls) as well as a set of specialized functions (like playing announcements, voice recognition and text-to-speech conversion).
位于PSTN中的SN与SCP一样，执行服务控制功能[1、2、3]。它执行服务逻辑并指示交换机如何完成调用。SN还执行某些切换功能（如呼叫桥接）以及一组专用功能（如播放公告、语音识别和文本到语音转换）。
Service Management System
服务管理系统
The SMS performs administration and management of service logic and customer-related data on the SN. It is responsible for the replication of content provider profiles and provision of these data on the SN. These functions are non-real time.
SMS对SN上的服务逻辑和客户相关数据进行管理。它负责复制内容提供商配置文件并在SN上提供这些数据。这些函数是非实时的。
Web Users
____________
O -------------------------- | Internet |-------------------
------------ |
|
|
---------------- -------------- ------------
| Service Node | D | Service | B |Web Server|
| (SN) |------------| Management |---------------| |
| | |System (SMS)| | |
| | A -------------- | |
| |-----------------------------------------| |
---------------- ------------
| |
| I | C
| |
----------- ---------
|Mobile | |Central|
|Switching| |Office |
| Center | ---------
----------- |
| |
| |
O O
Web Users
____________
O -------------------------- | Internet |-------------------
------------ |
|
|
---------------- -------------- ------------
| Service Node | D | Service | B |Web Server|
| (SN) |------------| Management |---------------| |
| | |System (SMS)| | |
| | A -------------- | |
| |-----------------------------------------| |
---------------- ------------
| |
| I | C
| |
----------- ---------
|Mobile | |Central|
|Switching| |Office |
| Center | ---------
----------- |
| |
| |
O O
Mobile Wireline PSTN Users Users
移动有线PSTN用户
Figure 11: Overall Interconnection Architecture of the Lucent System
图11：朗讯系统的整体互连架构
A Web user, who has simultaneous access to the Web and telephone services (this can be achieved, for example, by having an ISDN connection), is browsing through a sales catalogue and deciding to speak to a sales representative.
同时访问网络和电话服务（例如，通过ISDN连接可以实现）的网络用户正在浏览销售目录并决定与销售代表通话。
When the Web user clicks a button inviting a telephone call from the sales office, the Web Server sends a message to the SN over the A interface, thus crossing the Internet-to-PSTN boundary. By matching the information received from the Web Server with the content provider profile that had been previously loaded and activated by the SMS over the D interface, the SN recognizes the signal.
当Web用户单击一个按钮，邀请销售办公室拨打电话时，Web服务器通过a接口向SN发送一条消息，从而跨越Internet到PSTN的边界。通过将从Web服务器接收到的信息与先前由SMS通过D接口加载和激活的内容提供商简档相匹配，SN识别信号。
At this point, the SN calls the Web user. The user answers the call, hears an announcement, e.g., "Please wait, while we are connecting you to the sale agent", and is waiting to be connected to the sale agent. Then the SN invokes service logic as indicated in the profile.
此时，SN调用Web用户。用户接听电话，听到通知，例如，“请稍候，我们正在将您连接到销售代理”，并正在等待连接到销售代理。然后，SN调用概要文件中指示的服务逻辑。
The execution of this logic selects an appropriate sales agent to call based on the time of the day. It is 8 P.M. in New York where the Web user is located, and the New York sales office has closed. The San Francisco office, however, is still open, and so the SN makes a call to an agent in that office. Finally, the SN bridges the two calls and establishes a two-party call between the sales agent and the Web user.
此逻辑的执行根据一天中的时间选择要调用的适当销售代理。网络用户所在地纽约的时间是晚上8点，纽约销售办事处已经关闭。然而，旧金山办事处仍然是开放的，所以SN打电话给该办事处的代理人。最后，SN桥接这两个呼叫，并在销售代理和Web用户之间建立一个双方呼叫。
Lucent developed the Service Support Transfer Protocol (SSTP) for communications between the SN and Web Server. SSTP is of a request/response type running on top of a reliable transport layer, such as TCP. The Web Server sends a request to the SN to invoke a service and the SN responds with a message indicating either success or failure. Note that SSTP engages only the service control function [1, 2, 3] of the SN.
朗讯为SN和Web服务器之间的通信开发了服务支持传输协议（SSTP）。SSTP是一种运行在可靠传输层（如TCP）之上的请求/响应类型。Web服务器向SN发送一个调用服务的请求，SN用一条指示成功或失败的消息进行响应。请注意，SSTP仅启用SN的维修控制功能[1、2、3]。
In this direction, three kinds of messages may be sent: the Transaction Initiator message, the Data Message, and the End of Data message.
在这个方向上，可以发送三种消息：事务发起方消息、数据消息和数据结束消息。
The latter two messages are needed if the service to be invoked involves data (such as the case in click-to-fax, click-to-fax-back and voice-access-to-content). This was so designed to handle the varying size of data and to ensure that the size of each stream is within the allowable size of the underlying transport packet data unit (imposed by some implementations of TCP/IP).
如果要调用的服务涉及数据（例如单击以传真、单击以发回传真和语音访问内容），则需要后两条消息。这样设计是为了处理不同大小的数据，并确保每个流的大小在底层传输包数据单元的允许大小内（由TCP/IP的某些实现强制）。
a. Transaction Initiator
a. 事务启动器
This message provides all the necessary information but data for invoking a service. It includes the following information elements:
此消息提供调用服务所需的所有信息，但不包括数据。它包括以下信息元素：
+ Transaction ID, which uniquely specifies a service request. The same transaction ID should be used for all the accompanying data-related messages, if the service request involves data. One way for generating unique transaction IDs is to concatenate the information: date, time, Web Server ID (uniquely assigned for each one connected to the SN), and transaction sequence number (a cyclic counter incremented for each service request).
+ 事务ID，它唯一地指定服务请求。如果服务请求涉及数据，则应为所有附带的数据相关消息使用相同的事务ID。生成唯一事务ID的一种方法是连接信息：日期、时间、Web服务器ID（为连接到SN的每个ID唯一分配）和事务序列号（为每个服务请求递增的循环计数器）。
+ Service ID, which specifies the service to be invoked. The service may be click-to-dial-back, click-to-fax, click-to-fax-back or voice-access-to-content.
+ 服务ID，指定要调用的服务。该服务可以是单击回拨、单击传真、单击回传真或通过语音访问内容。
+ Content Provider ID, which uniquely represents the content provider. This information is the key to accessing the content provider's service logic and data on the SN.
+ 内容提供商ID，它唯一地表示内容提供商。该信息是访问SN上内容提供商的服务逻辑和数据的关键。
+ Content Provider Directory Number, which is the telephone or fax number of the content provider to be called through the PSTN.
+ 内容提供商目录号，是通过PSTN呼叫的内容提供商的电话或传真号码。
+ User Directory Number, which is the telephone or fax number of the user requesting the service.
+ 用户目录号，是请求服务的用户的电话或传真号码。
+ Billed Party, which specifies the party (either the user or content provider), to be billed.
+ 计费方，指定要计费的一方（用户或内容提供商）。
In addition, optional parameters may be sent from the Web Server to the SN. For example, a retry parameter may be sent to specify the number of times the SN will attempt to complete a service request upon failure before the transport connection times out.
此外，可选参数可以从Web服务器发送到SN。例如，可以发送重试参数来指定在传输连接超时之前，SN在失败时尝试完成服务请求的次数。
b. Data Message
b. 数据电文
This message provides the (encapsulated) user data part of a service request. For example, in the case of click-to-fax-back such data are the content to be faxed to the user. Each message is composed of the transaction ID and a data segment. The transaction ID must be the same as that of the transaction initiator part first invoking the service.
此消息提供服务请求的（封装的）用户数据部分。例如，在单击传真回的情况下，这些数据是要传真给用户的内容。每条消息由事务ID和数据段组成。事务ID必须与首先调用服务的事务启动器部分的ID相同。
c. End of Data Message
c. 数据报文结束
This message contains the transaction ID and the end of data delimiter. The transaction ID is the same as that of the relevant transaction initiator message.
此消息包含事务ID和数据结束分隔符。事务ID与相关事务启动器消息的ID相同。
The SN must respond to a service request from the Web Server. The response message consists of the information elements:
SN必须响应来自Web服务器的服务请求。响应消息由以下信息元素组成：
transaction ID, service type, result, time, and error code.
事务ID、服务类型、结果、时间和错误代码。
+ Transaction ID, which is the same as that of the original service request.
+ 事务ID，与原始服务请求的事务ID相同。
+ Service Type, which is the same as that of the original service request.
+ 服务类型，与原始服务请求的服务类型相同。
+ Result, which is either success or failure.
+ 结果，要么成功，要么失败。
+ Time, which indicates the time of the day completing the request.
+ 时间，表示一天中完成请求的时间。
+ Error Code, which gives the reason for failure. Possible reasons for failure are content provider telephone (or fax) busy, content provider telephone (or fax) no answer, user telephone busy, user refusal to complete, user no answer, nuisance control limit reached, and content provider telephone (or fax) not in the SN database.
+ 错误代码，它给出了失败的原因。失败的可能原因有：内容提供商电话（或传真）占线、内容提供商电话（或传真）无人接听、用户电话占线、用户拒绝完成、用户无人接听、达到滋扰控制限制以及内容提供商电话（或传真）不在SN数据库中。
For the click-to-fax and click-to-fax-back services, the Lucent system implemented only the case where the data to be sent as facsimile reside in the Web server. There are at least three messages that need to be sent from the Web server to the Service Node for these services.
对于点击传真和点击传真回服务，朗讯系统仅实现了将作为传真发送的数据驻留在Web服务器中的情况。对于这些服务，至少有三条消息需要从Web服务器发送到服务节点。
The first message is the Transaction Initiator that identifies the service type as well as a unique Transaction ID. It also includes the sender/receiver fax number.
第一条消息是用于标识服务类型和唯一事务ID的事务发起方。它还包括发送方/接收方传真号码。
The next is one or more messages of the data to be faxed. Each message carries the same unique Transaction ID as the above.
下一个是要传真的一条或多条数据消息。每条消息都带有与上述相同的唯一事务ID。
Last comes the end of message. It consists of the Transaction ID (again, the same as that of the messages preceding it) and the end of data delimiter.
最后是消息的结尾。它由事务ID（同样，与它前面的消息的ID相同）和数据分隔符结尾组成。
Upon receiving these messages, the Service Node, equipped with the special resource of a fax card, converts the data into the G3 format, calls the receiver fax, and sends back the result to the Web server immediately. Note that the receiver fax busy or no answer is interpreted as failure. Further, while the receiver fax answering the call is interpreted as success, it does not necessarily mean that the fax would go through successfully.
在接收到这些消息后，服务节点（配备有传真卡的特殊资源）将数据转换为G3格式，调用接收方传真，并立即将结果发送回Web服务器。请注意，接收器传真忙或无应答被解释为失败。此外，虽然应答呼叫的接收方传真被解释为成功，但并不一定意味着传真将成功通过。
This interface is responsible for uploading the content provider profile from the Web Server to the SMS and for managing the information against any possible corruption. The SN verifies the Content Provider ID and the Content Provider Directory Number sent by the Web Server with the content provider profile pre-loaded from the SMS.
此接口负责将内容提供商配置文件从Web服务器上载到SMS，并负责管理信息以防止任何可能的损坏。SN使用从SMS预加载的内容提供商配置文件验证Web服务器发送的内容提供商ID和内容提供商目录号。
The content provider profile was based on ASN.1 [4] structure and SNMP [5] was used to set/get the object identifiers in the SMS database.
内容提供商配置文件基于ASN.1[4]结构，SNMP[5]用于设置/获取SMS数据库中的对象标识符。
Following is an example of the simple MIB available on the SMS.
下面是SMS上可用的简单MIB示例。
inwebContProviderTable OBJECT-TYPE
SYNTAX SEQUENCE OF InwebContProviderEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
" A table containing Content Provider profiles "
:= { inweb 1}
inwebContProviderTable OBJECT-TYPE
SYNTAX SEQUENCE OF InwebContProviderEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
" A table containing Content Provider profiles "
:= { inweb 1}
inwebContProviderEntry OBJECT-TYPE
SYNTAX InwebContProviderEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
" A conceptual row of the inweb. Each row
contains profile of one Content Provider"
INDEX { inwebSmsNumber }
:= { inwebContProviderTable 1 }
inwebContProviderEntry OBJECT-TYPE
SYNTAX InwebContProviderEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
" A conceptual row of the inweb. Each row
contains profile of one Content Provider"
INDEX { inwebSmsNumber }
:= { inwebContProviderTable 1 }
InwebContProviderEntry := SEQUENCE {
inwebSmsNumber Integer32,
inwebContentProviderId Integer32,
inwebContentProviderPhoneNumber Integer32,
inwebContentProviderFaxNumber Integer32
}
InwebContProviderEntry := SEQUENCE {
inwebSmsNumber Integer32,
inwebContentProviderId Integer32,
inwebContentProviderPhoneNumber Integer32,
inwebContentProviderFaxNumber Integer32
}
inwebSmsNumber OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
" Serial number of the SMS - used for SNMP indexing "
:= { inwebContProviderEntry 1 }
inwebSmsNumber OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
" Serial number of the SMS - used for SNMP indexing "
:= { inwebContProviderEntry 1 }
inwebContentProviderId OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-create
STATUS current
DESCRIPTION
" A number that uniquely identifies each Content
Provider "
:= { inwebContProviderEntry 2 }
inwebContentProviderId OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-create
STATUS current
DESCRIPTION
" A number that uniquely identifies each Content
Provider "
:= { inwebContProviderEntry 2 }
inwebContentProviderPhoneNumber OBJECT-TYPE SYNTAX Integer32 MAX-ACCESS read-create STATUS current
inwebContentProviderPhoneNumber对象类型语法整数32 MAX-ACCESS读取创建状态当前
DESCRIPTION
" Content Provider's Phone Number "
:= { inwebContProviderEntry 3 }
DESCRIPTION
" Content Provider's Phone Number "
:= { inwebContProviderEntry 3 }
inwebContentProviderFaxNumber OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-create
STATUS current
DESCRIPTION
" Content Provider's Fax Number "
:= { inwebContProviderEntry 4 }
inwebContentProviderFaxNumber OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-create
STATUS current
DESCRIPTION
" Content Provider's Fax Number "
:= { inwebContProviderEntry 4 }
The Lucent prototype addressed the security issues concerning the interface between the Web Server and the SN. Those concerning the interface between the Web Server and SMS, which was based in SNMP, were handled by the built-in security features of SNMP.
朗讯原型解决了Web服务器和SN之间接口的安全问题。有关Web服务器和SMS之间的接口的问题（基于SNMP）由SNMP的内置安全功能处理。
+ Secure Communication Links
+ 安全通信链路
If the Network Operator (PSTN provider) is also the Web Service provider, the Web Server and SN/SMS will communicate over a corporate intranet. This network is almost always protected by the corporation's firewall and so can be deemed secure. This was the case handled by the Lucent prototype.
如果网络运营商（PSTN提供商）也是Web服务提供商，则Web服务器和SN/SMS将通过公司内部网进行通信。该网络几乎总是受到公司防火墙的保护，因此可以认为是安全的。这是朗讯原型公司处理的案件。
Nevertheless, if different corporations serve as the Network Operator and the Web Service Provider, then it is likely that there may not exist a dedicated secure communication link between the Web Server and SN/SMS. This raises serious security considerations. One possible solution is to use Virtual Private Networks (VPN). VPN features support authentication of the calling and called parties and encryption of the messages sent over insecure links (such as those on the Internet).
然而，如果不同的公司充当网络运营商和Web服务提供商，则Web服务器和SN/SMS之间可能不存在专用的安全通信链路。这引起了严重的安全考虑。一种可能的解决方案是使用虚拟专用网络（VPN）。VPN功能支持对主叫方和被叫方进行身份验证，并对通过不安全链路（如互联网上的链路）发送的消息进行加密。
+ Non-Repudiation
+ 不可抵赖
All transactions were logged on both the Web Server and the Service Node to account for all operations in case of doubt or dispute. The log information on the SN may also be used to generate bills.
所有事务都记录在Web服务器和服务节点上，以便在出现疑问或争议时说明所有操作。序列号上的日志信息也可用于生成票据。
+ Malicious Requests of Users
+ 用户的恶意请求
A user may make repeated requests to a content provider directory number maliciously. This scenario was handled by setting a Nuisance Control Limit (NCL) on either the SN or the Web Server or both. The NCL has two parameters: one defining the number of requests from a
用户可能恶意地重复请求内容提供商目录号。通过在SN或Web服务器或两者上设置妨害控制限制（NCL）来处理此场景。NCL有两个参数：一个参数定义来自
user and the other the period over which these requests takes place.
用户和另一方记录这些请求发生的时间。
A user may also attempt to request a call from a directory number other than that of a content provider. This scenario was handled by verifying the directory number (and the content provider ID) against the database on the SN containing all the content provider information. If the directory number (or the content provider ID) was not in the database, the request would be rejected.
用户还可以尝试从内容提供商以外的目录号码请求呼叫。通过对照SN上包含所有内容提供商信息的数据库验证目录号（和内容提供商ID）来处理此场景。如果目录号（或内容提供商ID）不在数据库中，则请求将被拒绝。
The Web Call Center is an Intelligent Network System that accepts requests from Internet nodes for services to be provided on the PSTN. As the name suggests, it was designed to support a cluster of services that, taken together, provide a subset of the features of a Call Center, with almost all user interactions provided via World Wide Web requests and responses. See the appendix for a background description of Call Center Features.
Web呼叫中心是一个智能网络系统，它接受来自Internet节点的请求，以便在PSTN上提供服务。顾名思义，它被设计为支持一组服务，这些服务一起提供呼叫中心功能的子集，几乎所有用户交互都通过万维网请求和响应提供。有关呼叫中心功能的背景说明，请参见附录。
From an Intelligent Network perspective, there are a number of services that, when combined, provide the Call Center features. The Call Center features as implemented supported the scenario in which a customer makes a request to be called back by an agent at a time of the customer's choosing to discuss an item of interest to him or her. The agent will be selected based on his or her availability and expertise in this topic; the agent will be told whom he or she is calling and the topic of interest, and then the agent will be connected to the customer.
从智能网络的角度来看，有许多服务在组合时提供呼叫中心功能。呼叫中心功能的实现支持这样一种场景：客户在选择讨论他或她感兴趣的项目时，请求代理回电。代理人将根据其在该主题中的可用性和专业知识进行选择；代理将被告知他或她正在给谁打电话以及感兴趣的话题，然后代理将被连接到客户。
In addition, the individual services that were deployed to support this scenario provided support for management of the list of available agents as well. This involved allowing the agent to "log into" and "out of" the system and to indicate whether the agent was then ready to handle calls to the customer. The list of services, as seen from a user perspective, follows.
此外，为支持此场景而部署的各个服务也为可用代理列表的管理提供了支持。这涉及允许代理“登录”和“退出”系统，并指示代理是否准备好处理与客户的呼叫。从用户角度来看，服务列表如下所示。
The services support:
这些服务支持：
i) Customer Request service - the customer explores a corporate Web site, selects a link that offers to request an agent to call the customer back and then is redirected to the Web Call Center server. This presents customer with a form asking for name, the telephone number at which he or she wishes to be called, and the time at which the call is to be made. Note will also be made of the page to which the customer was referred to when he or she was redirected. Once the form has been returned, the customer receives an acknowledgment page
i) 客户请求服务-客户浏览公司网站，选择一个链接，请求代理回拨客户，然后重定向到Web呼叫中心服务器。这会向客户提供一份表格，要求提供姓名、他或她希望拨打的电话号码以及拨打电话的时间。还将记录客户重定向时所指的页面。表单返回后，客户将收到一个确认页面
listing the parameters he or she has entered.
列出他或她输入的参数。
ii) Agent Registration/Logon - An agent requests a "login" page on the Web Call Center server. The service checks whether it has a record of an agent present at the Internet node from which th call is made. If not, then the caller will be sent a form allowing him or her to enter the service identity, the company's agent identifier and password. On return, the service identity and company agent identifier will be checked against a list of known identities. If found, the password will be checked, and if this matches the record held by the service then a new session record is made of this identity and the Internet node from which the call has been made.
ii）代理注册/登录-代理请求Web呼叫中心服务器上的“登录”页面。该服务检查是否有一个代理的记录，该代理位于发出该呼叫的Internet节点上。如果没有，则会向呼叫者发送一份表格，允许其输入服务标识、公司的代理标识符和密码。返回时，将对照已知标识列表检查服务标识和公司代理标识。如果找到密码，将检查密码，如果密码与服务持有的记录匹配，则会根据此标识和进行呼叫的Internet节点创建新的会话记录。
NB: This is very similar to the Universal Personal Telecommunications (UPT) service feature "register for incoming calls". It implies that the identified person has exclusive use of the Internet node from that point onwards, so messages for them can be directed there.
注意：这与通用个人电信（UPT）服务功能“来电登记”非常相似。这意味着从该点开始，被识别的人对互联网节点有独占使用权，因此可以将他们的消息定向到那里。
iii) Agent Ready - an agent who has already logged on can indicate that he or she is ready by requesting an appropriate "ready" page on the Web Call Center Server. The service will match the agent by the Internet node Identifier and Agent Identity passed along with the Web request against its list of "active" agents. It will mark them as being ready to handle calls in its list of available agents (with their pre-defined skill set).
iii）代理就绪-已登录的代理可以通过在Web呼叫中心服务器上请求适当的“就绪”页面来指示他或她已就绪。服务将通过Internet节点标识符和随Web请求传递的代理标识与其“活动”代理列表匹配代理。它将在可用代理列表中（使用他们预定义的技能集）将他们标记为准备好处理呼叫。
iv) Agent Not Ready - an agent can request an appropriate "ready" page on the Web Call Center Server to indicate that he or she is temporarily not ready to handle calls.
iv）代理未就绪-代理可以在Web呼叫中心服务器上请求一个适当的“就绪”页面，以表明他或她暂时没有准备好处理呼叫。
v) Agent Logoff - an agent can request an appropriate "Logout" page on the Web Call Center Server to indicate that he or she is no longer associated with a particular Internet node. The service will match the agent by the Internet Node Identifier and Agent Identity passed along with the Web request against its list of "active" agents. Once found, the session record for that agent is removed and the caller is notified of this with an acknowledgment page.
v) 代理注销-代理可以请求Web呼叫中心服务器上的适当“注销”页面，以表明他或她不再与特定Internet节点关联。服务将通过Internet节点标识符和随Web请求传递的代理标识与其“活动”代理列表匹配代理。一旦找到，该代理的会话记录将被删除，并通过确认页面通知调用者。
NB: This is very similar to the UPT "unregister" service feature.
注意：这与UPT的“注销”服务功能非常相似。
vi) Call Center Agent Selection and Notification - When the time that the customer selected has arrived and an available agent with the right skills has been selected from the appropriate list, this service will send a notification to the Internet node associated with that agent. A dedicated server is assumed to be running on the agent's machine that, on receiving the notification, triggers the agent's browser into requesting a "Agent Call In" page from the Web Call Center Server. Once the agent's machine has made this request,
vi）呼叫中心代理选择和通知-当客户选择的时间到达并且从适当的列表中选择了具有正确技能的可用代理时，此服务将向与该代理关联的Internet节点发送通知。假定在代理的机器上运行一个专用服务器，该服务器在收到通知时触发代理的浏览器，从Web呼叫中心服务器请求“代理呼叫入”页面。一旦代理的机器发出此请求，
he or she will be told that there is a customer to call.
他或她会被告知有客户要打电话。
NB: This is similar to a "Message Waiting" or "Wake Up Call" service.
注意：这类似于“消息等待”或“唤醒呼叫”服务。
Note: As implemented, the agent is led automatically into the following service (the returned Web page includes an automatic reload command).
注意：在实现时，代理将自动引导到以下服务中（返回的网页包含自动重新加载命令）。
vii) Agent Instruction - a selected agent makes a request of the "Customer Processing" page on the Web Call Center Server. The Internet node Identifier and Agent Identity the agent uses will be matched against a list of agents expected to handle calls, and the instructions for the calls will be returned to the agent.
vii）代理指令-所选代理向Web呼叫中心服务器上的“客户处理”页面发出请求。代理使用的Internet节点标识符和代理标识将与预期处理呼叫的代理列表相匹配，并且呼叫指令将返回给代理。
NB: This is similar to a "Voice Mail Replay" message service, but in this case the message is automatically generated; there is no associated voice mail record feature accessible.
注意：这类似于“语音邮件重播”消息服务，但在这种情况下，消息是自动生成的；没有可访问的关联语音邮件记录功能。
Note: As implemented, the instructions page will include a number of buttons, allowing the agent to view the page the customer was looking at when he or she made the request, and to trigger the customer callback (as described next).
注意：实施时，“说明”页面将包括多个按钮，允许代理查看客户发出请求时正在查看的页面，并触发客户回调（如下所述）。
ix) Agent/Customer Telephony Callback - the agent will make a request of a "dial-back" page on the Web Call Center Server. The Internet node Identifier and Agent Identity he or she uses will be matched against a list of agents expected to handle calls, and, when the appropriate records have been found, the service will make the telephone call through to the customer and then connect the agent to this telephone call (using the telephone number registered in the respective Call Center service record).
ix）代理/客户电话回拨-代理将请求Web呼叫中心服务器上的“回拨”页面。他或她使用的Internet节点标识符和代理标识将与预期处理呼叫的代理列表相匹配，并且，当找到适当的记录时，服务将通过电话呼叫客户，然后将代理连接到此电话呼叫（使用相应呼叫中心服务记录中登记的电话号码）。
The Siemens Web Call Center used an existing IN system and service logic that supported Call Center features. The scenario it supports is very similar to the Siemens IN-based Call Center on which it was based; one of the goals was to minimize changes to the service offered. It is also virtually identical to the service "Internet Requested Telephony Dial-back" provided by the Lucent system.
西门子网络呼叫中心使用支持呼叫中心功能的现有系统内和服务逻辑。它所支持的场景与它所基于的西门子IN呼叫中心非常相似；目标之一是尽量减少对所提供服务的更改。它实际上也与朗讯系统提供的“互联网请求电话回拨”服务完全相同。
As provided via the Internet, the services involved are mostly the same as those provided via the PSTN and IN alone. The main differences lie in the use of the World Wide Web as an interface to the services rather than a telephone, SSP, and Intelligent Peripheral. Also, the feature by which a telephone call is made
由于是通过互联网提供的，所涉及的服务大多与通过PSTN提供的服务相同，且仅限于互联网。主要区别在于使用万维网作为服务的接口，而不是电话、SSP和智能外围设备。此外，拨打电话的功能
between the agent and the customer is implemented within the IN system in a different way; this is the only element in which the PSTN is involved.
在系统内以不同的方式实现代理和客户之间的关系；这是PSTN涉及的唯一元素。
The general arrangement for the Web Call Center system is shown in Figure 7. The components that were added to an existing IN system to deal with the Internet interface are described next.
Web呼叫中心系统的总体布置如图7所示。下面将描述添加到现有IN系统中以处理Internet接口的组件。
In addition to the SCP, SSP and SMS that were part of the original IN-based system, another unit was included to send notification messages to agents; in the IN system the agents were sent "wake up" telephone calls when they were required to handle their next customers' call back. This unit is called the "Internet Intelligent Peripheral", and its use is described later under "Non-World Wide Web Interactions".
除了原始基于In的系统中的SCP、SSP和SMS之外，还包括另一个向代理发送通知消息的单元；在in系统中，当代理被要求处理下一个客户的回电时，他们会接到“叫醒”电话。该装置被称为“互联网智能外围设备”，其使用将在后面的“非万维网交互”中描述。
As there was a need to re-use as many of the existing IN components unchanged, a Gateway unit to deal with the interface between the Internet and the SCP was provided. This injected INAP (Intelligent Network Application Protocol) messages into the SCP, making it think that it had received an Initial DP trigger from an SSP. It also intercepted the "Connect To Resource" and "Prompt and Collect" INAP messages sent from the SCP, acting on these to return the parameters generated by the Internet users when they filled in the forms that triggered the service transaction. It also translated the "Play Announcement" message sent to the Intelligent Peripheral into a form that it could use. Finally, it passed on the INAP message used by the SCP to trigger SSP into making the telephone call back.
由于需要重复使用尽可能多的现有IN组件，因此提供了一个网关单元来处理Internet和SCP之间的接口。这将INAP（智能网络应用协议）消息注入SCP，使其认为已从SSP接收到初始DP触发器。它还截获了SCP发送的“连接到资源”和“提示并收集”INAP消息，并根据这些消息返回互联网用户在填写触发服务交易的表单时生成的参数。它还将发送到智能外围设备的“播放公告”信息转换为它可以使用的形式。最后，它传递由SCP使用的INAP消息，以触发SSP进行电话回拨。
In the IN/PSTN-based system, the services have contact with the customers and agents via their telephones, SSPs, and Intelligent Peripherals programmed to play announcements to them and to capture their responses. These responses are indicated by DTMF tones sent by pressing keys on the telephones.
在基于In/PSTN的系统中，这些服务通过其电话、SSP和智能外围设备与客户和代理联系，这些设备被编程为向他们播放公告并捕获他们的响应。这些响应由按电话上的键发送的DTMF音表示。
In this case, almost all interactions are provided via World Wide Web requests and responses. The sequence of announcements and responses for each service are "collapsed" into individual form filling transactions, and the requests are not limited to digits (or "star" and "hash"). The implications of the use of forms on service operation are covered in more detail later (under HTTP/IN Service mapping).
在这种情况下，几乎所有的交互都是通过万维网请求和响应提供的。每个服务的通知和响应序列被“折叠”成单独的表单填写事务，请求不限于数字（或“星”和“哈希”）。稍后（在HTTP/in服务映射下）将更详细地介绍使用表单对服务操作的影响。
When provided via the IN/PSTN-based system, the services are passed the Calling Line Identity (CLI) of the caller and the number the caller dials (the DN). The CLI value is used extensively to identify the caller and (in the case of the agent) to index into service data tables to decide what to do next. While an equivalent value to the DN is passed to the Web-based transactions as the requested Universal Resource Locator (URL), the CLI cannot be given reliably. The nearest equivalent caller identifier is the IP Address of the customer or agent's machine. However, the use of HTTP proxies means that this "original" Internet node Address may not be available; if a proxy is used then its IP Address will be associated with the request.
当通过基于IN/PSTN的系统提供服务时，会向服务传递呼叫者的呼叫线路标识（CLI）和呼叫者拨打的号码（DN）。CLI值广泛用于标识调用方，并（对于代理）索引到服务数据表中，以决定下一步要做什么。当DN的等效值作为请求的通用资源定位器（URL）传递给基于Web的事务时，无法可靠地提供CLI。最近的等效呼叫者标识符是客户或代理机器的IP地址。然而，HTTP代理的使用意味着这个“原始”互联网节点地址可能不可用；如果使用代理，则其IP地址将与请求关联。
In providing these Call Center features the customer only has one Web-based transaction; that of providing the initial request for a PSTN telephone callback. To do so he or she will have to fill in a form so as to specify not only the time to be called back, but also the telephone number to be reached. These values can be used if needed to identify the customer, and so the problem of originating Internet Node ambiguity is not relevant.
在提供这些呼叫中心功能时，客户只有一个基于Web的事务；提供PSTN电话回拨的初始请求。要做到这一点，他或她必须填写一份表格，不仅要注明回拨的时间，还要注明要拨打的电话号码。如果需要，可以使用这些值来识别客户，因此发起Internet节点模糊性的问题并不相关。
With the agents, however, there are sequences of coupled transactions, and the particular sequence must be identified. There will be a number of such transactions being carried out at once, and there needs to be some identifier to show which agent is being handled in each case.
然而，对于代理，存在耦合事务的序列，并且必须识别特定的序列。一次将执行许多这样的交易，并且需要一些标识符来显示在每种情况下处理的是哪个代理。
Such an identifier is not part of a sequence of basic Web transactions. In a Web transaction, the HTTP Client/Web Browser makes a request, and the HTTP Server will respond to this, normally including some content in its reply message that will be processed by the browser, after which it closes the TCP connection. That's the end of the transaction; the HTTP client and server cannot normally maintain state information beyond this point. Any sequence is reduced to a set of unrelated transactions.
这种标识符不是基本Web事务序列的一部分。在Web事务中，HTTP客户端/Web浏览器发出请求，HTTP服务器将对此做出响应，通常在其回复消息中包含一些内容，这些内容将由浏览器处理，然后关闭TCP连接。交易到此结束；HTTP客户端和服务器通常无法维护超出此点的状态信息。任何序列都被简化为一组不相关的事务。
A result of this simple pattern is that any state information reflecting longer or more complex interactions must be stored (at least partially) in the client system. One approach is the use of cookies [6]. These can be set by HTTP servers as part of their response to a request, and will be sent back with all subsequent requests for appropriate URLs as extra HTTP headers. These cookies allow the HTTP server to identify the client in the following requests, so that it can continue an extended session with the client.
这种简单模式的一个结果是，任何反映更长或更复杂交互的状态信息都必须（至少部分）存储在客户机系统中。一种方法是使用cookie[6]。这些可以由HTTP服务器设置，作为其对请求响应的一部分，并将与对适当URL的所有后续请求一起作为额外的HTTP头发送回去。这些cookies允许HTTP服务器在以下请求中标识客户端，以便它可以继续与客户端的扩展会话。
Cookies are used in providing the Internet Call Center. Persistent cookies are installed into the Web Browser on machines that are to be used by call center agents as a service management (pre-service) task. The cookie value is unique to the machine and is used to index into a list of machine IP addresses that is stored as part of the service data.
Cookie用于提供互联网呼叫中心。持久性Cookie安装在计算机的Web浏览器中，这些计算机将被呼叫中心代理用作服务管理（服务前）任务。cookie值对于机器是唯一的，用于索引到作为服务数据一部分存储的机器IP地址列表中。
Also, a session cookie is stored onto the agent's machine when the agent registers, and is cleared when he or she de-registers. This is used to identify the agent and so the IP address of the node with which the agent is associated (and from which the agent's subsequent requests should originate). The services that interact with Call Center agents use the agent session cookie value as an identifier; in principle this is unnecessary but it does simplify the session data lookup procedure. The rest of the services use the persistent machine identifier in place of the CLI, indexing into their service data using it. Both cookies are sent with each agent request; if they are not present, then the request is redirected to other services (for example to the agent Logon service).
此外，当代理注册时，会话cookie存储在代理的机器上，当代理注销时，会话cookie被清除。这用于标识代理以及与代理关联的节点的IP地址（以及代理的后续请求应来自该节点）。与呼叫中心代理交互的服务使用代理会话cookie值作为标识符；原则上这是不必要的，但它确实简化了会话数据查找过程。其余的服务使用持久性机器标识符代替CLI，并使用它索引到它们的服务数据中。两个cookie随每个代理请求一起发送；如果它们不存在，则请求将重定向到其他服务（例如代理登录服务）。
All of the client-initiated services require user interaction. With the IN/PSTN-based system, the majority of the services are typified by the callers being connected to an announcement unit that plays them a list of choices and captures their selection. The caller can pre-dial the digits needed; in this case the prompts are not needed and are not made.
所有客户端启动的服务都需要用户交互。在基于IN/PSTN的系统中，大多数服务的典型特征是呼叫者连接到一个公告单元，该单元向呼叫者播放选择列表并捕获他们的选择。呼叫者可以预先拨出所需的数字；在这种情况下，不需要也不进行提示。
The pattern of operation is somewhat different in the Internet case, as the initial HTTP request returns a response, after which the Web transaction has ended. Where that initial response returns a form to be filled in by the caller, subsequently submitting the form initiates a new HTTP transaction. This is all part of one instance of service, however. The service consists of two request/response pairs in tandem.
在Internet情况下，操作模式有些不同，因为初始HTTP请求返回一个响应，然后Web事务结束。其中，初始响应返回一个由调用方填写的表单，随后提交该表单将启动一个新的HTTP事务。然而，这都是一个服务实例的一部分。该服务由两个串联的请求/响应对组成。
Although it is possible to design a service to handle this pair of Web transactions as a single unit, it may be better to reconfigure it. The design of a service that deals with two Web exchanges as a single extended transaction is quite complex. It must maintain state across the pair of Web exchanges, and it has to handle a number of failure cases including dealing with time-outs and "out of time" submission of forms. The alternative is to split the service into two sub-features. The first of these reflects the initial request and delivery of the form by return, with the second one dealing with processing of the submitted form and returning any confirmation by reply.
虽然可以设计一个服务，将这对Web事务作为一个单元来处理，但是重新配置它可能更好。将两个Web交换作为单个扩展事务处理的服务的设计相当复杂。它必须在两个Web Exchange之间维护状态，并且必须处理许多失败案例，包括处理超时和“超时”提交表单。另一种方法是将服务分为两个子功能。其中第一个反映了最初的请求和通过返回方式提交的表格，第二个涉及处理提交的表格并通过回复返回任何确认。
The services offered don't all require form-filling, and so can be treated as a single IN feature. There are two cases where forms are required. The first of these is the Customer Request service, while the other one is the "Agent Registration" service. In both cases the initial Web transaction (by which the form is requested and returned to the client) need not involve specific service logic processing; the initial delivery of the form to a customer or agent can be handled by a "normal" Web Server. In both cases the service logic is only triggered when the form is submitted; this means that, again, each of the services can be treated as a single IN feature.
提供的服务并不都需要填写表单，因此可以将其视为单一功能。有两种情况需要表格。第一个是客户请求服务，另一个是“代理注册”服务。在这两种情况下，初始Web事务（通过该事务请求表单并将其返回给客户机）不需要涉及特定的服务逻辑处理；表单向客户或代理的初始交付可以由“普通”Web服务器处理。在这两种情况下，服务逻辑仅在提交表单时触发；这意味着，同样地，每个服务都可以被视为一个单一的功能。
The IN service logic that deals with these requests has a general pattern of action. An HTTP request is received, and this triggers the IN service logic into action. The service logic "sees" this as an Initial DP message and starts its processing as if it had been sent from an SSF. The SCF uses what appears to it to be an Intelligent Peripheral to collect the parameters of the request, and then to send back final announcements to the requesting entity.
处理这些请求的服务内逻辑具有一般的操作模式。接收到HTTP请求，这将触发服务内逻辑。服务逻辑将其“视”为初始DP消息，并开始处理，就像它是从SSF发送的一样。SCF使用它认为是智能外围设备的东西来收集请求的参数，然后将最终通知发送回请求实体。
The main difference, from the perspective of the IN service logic running on the SCF, is that the service does not need to instruct the SSF to make a temporary connection to the Intelligent Peripheral. It is as if this connection had already been made. Similarly, there is no need to close the service transaction by sending an explicit "Continue Execution" message to the SSF.
从SCF上运行的服务内逻辑的角度来看，主要区别在于服务不需要指示SSF临时连接到智能外围设备。就好像已经建立了这种联系。类似地，不需要通过向SSF发送显式的“继续执行”消息来关闭服务事务。
The sequence of "prompt/collect" instructions used to collect service parameters from a caller in an IN service maps quite well to a sequence of requests to extract a data value from the HTTP request, based on a tag. This is a fairly standard feature of Web Server CGI or Servlet processing. Using this mapping minimizes the changes to the service design, in that the service logic "sees" an Intelligent Peripheral to which it sends normal "Request Report Prompt & Collect" messages, and from which it receives data values in response.
用于从服务中的调用者收集服务参数的“prompt/collect”指令序列很好地映射到基于标记从HTTP请求提取数据值的请求序列。这是Web服务器CGI或Servlet处理的一个相当标准的特性。使用此映射可以最大限度地减少对服务设计的更改，因为服务逻辑“看到”一个智能外围设备，向其发送正常的“请求-报告-提示和收集”消息，并从中接收数据值作为响应。
All services have to fit in with the underlying HTTP interaction pattern, and so will be expected to send a final "Announce" instruction to the Intelligent Peripheral at the end of the service; this is done in many IN services anyway and in all of the service features described here. These announcements form the content returned to the Web Client.
所有服务都必须符合底层HTTP交互模式，因此在服务结束时将向智能外围设备发送最终的“公告”指令；无论如何，这是在许多in服务中以及在这里描述的所有服务功能中完成的。这些公告构成返回到Web客户端的内容。
There are two exceptions to the sole use of the World Wide Web for interaction. The first one occurs in the "Message Waiting"/"Wake Up Call" service by which the selected agent is informed of a callback request. World Wide Web transactions are very simple; the client browser makes a request for content associated with a particular HTTP URL, and the server sends a response, marking the end of the transaction. The server cannot make a spontaneous association with a client; it must be initiated by the client request.
仅使用万维网进行互动有两个例外。第一个出现在“Message Waiting”/“Wake Up Call”服务中，通过该服务将回调请求通知所选代理。万维网交易非常简单；客户端浏览器请求与特定HTTP URL关联的内容，服务器发送响应，标记事务结束。服务器无法与客户端进行自发关联；它必须由客户端请求启动。
While it would be possible for the server to defer closing an earlier transaction (by not sending back all of the content specified and leaving the TCP connection open) it was decided that an alternative scheme would be more convenient. The "wake up call" was arranged by an "Internet Intelligent Peripheral" sending a request to a daemon process running on the selected agent's machine, using the Finger protocol [7]. The daemon sent back a standard response, but in addition the Web Browser on the agent's machine was triggered into making a further HTTP request of the server. In this way the "Agent Instruction" transaction is started automatically, while still allowing it to use a normal HTTP request/response pattern.
虽然服务器可以延迟关闭较早的事务（通过不发回所有指定的内容并保持TCP连接打开），但决定使用另一种更方便的方案。“唤醒呼叫”是由“Internet智能外围设备”使用Finger协议向在所选代理机器上运行的守护进程发送请求来安排的[7]。守护进程发回了一个标准响应，但除此之外，代理机器上的Web浏览器被触发，向服务器发出进一步的HTTP请求。通过这种方式，“代理指令”事务将自动启动，同时仍允许它使用正常的HTTP请求/响应模式。
The second exception occurs in the final "Agent/Customer Telephony Callback" service. While this transaction is initiated by the agent selecting a link on the "call instructions page" returned to them, and includes a "confirmation" page being sent back to them in an HTTP response, the purpose of this service is to make a telephone connection via the PSTN between the agent's telephone and the customer's telephone. It is the only service element that involves the PSTN directly. From an IN/PSTN perspective, the resulting telephone connection is different from that provided in the scheme using the IN and PSTN alone. In this case, a PSTN call is made out to the agent's telephone, another call is made out to the customer's telephone, and these calls are bridged. This differs from the earlier scheme, in which the agent originated a call to the voice mail replay system, and this call was redirected to a new destination (the customer's telephone). As this feature differs in purpose from the other services, and it requires a different implementation within the IN and PSTN system, it was organized as a separate service in this case.
第二个异常发生在最终的“代理/客户电话回调”服务中。当代理选择返回给他们的“呼叫指示页面”上的链接并包括HTTP响应中发送回他们的“确认”页面时，该事务被启动，该服务的目的是通过PSTN在代理电话和客户电话之间建立电话连接。它是唯一直接涉及PSTN的服务元素。从IN/PSTN的角度来看，产生的电话连接不同于仅使用IN和PSTN的方案中提供的电话连接。在这种情况下，一个PSTN呼叫打到代理的电话，另一个呼叫打到客户的电话，这些呼叫被桥接。这与先前的方案不同，在该方案中，代理发起了对语音邮件重播系统的呼叫，并且该呼叫被重定向到新的目的地（客户的电话）。由于此功能的用途不同于其他服务，并且需要在in和PSTN系统中采用不同的实现方式，因此在本例中，它被组织为单独的服务。
In the case of this system, assumptions were made that the interface presented to requesting agents and customers was provided via a fire wall to deal with most attacks on the IN components. The interface appeared as a Web Server, and there was no direct access to the HTTP documents served, nor to the servlets providing the service logic.
在该系统的情况下，假设向请求代理和客户提供的接口是通过防火墙提供的，以应对对In组件的大多数攻击。该接口看起来像一个Web服务器，无法直接访问所服务的HTTP文档，也无法访问提供服务逻辑的servlet。
The Callback service was deemed to have simpler security requirements than other IN services as it was akin to a free phone "1-800" service access number; the agents work for the service subscriber and are not charged directly. Similarly, the requesting customer is not charged for his or her request, nor for the resulting call back. Service subscribers would be willing to pay the costs of telephone calls generated as a result of this cluster of services, and the costs of running the agent services could be charged directly to them. As such the authorization for service is defined by the contract between the service subscriber and the service provider.
回调服务被认为比其他IN服务具有更简单的安全要求，因为它类似于免费电话“1-800”服务接入号码；代理为服务订户工作，不直接收费。同样，提出请求的客户也不会因其请求或由此产生的回拨而收取费用。服务用户愿意支付由于这一服务集群而产生的电话费用，运行代理服务的费用可以直接向他们收取。因此，服务授权由服务订户和服务提供商之间的合同定义。
Authentication of agents was seen as a problem. As an interim measure, cookies were used, but this scheme delivers the cookie data as a plain text item (a header of the Web request). Secure Socket Layer connections were required for communication with the agent services, and this had an impact on the performance of the IN system.
代理的身份验证被视为一个问题。作为一项临时措施，使用了cookie，但此方案将cookie数据作为纯文本项（Web请求的头）交付。与代理服务的通信需要安全套接字层连接，这对系统内的性能有影响。
Security is seen as a major issue. A firewall was used to control access to the IN Components. Similarly, SSL was used for communication with the Agents, so as to protect the cookie values that they were sending with their requests.
安全被视为一个重大问题。防火墙用于控制对IN组件的访问。类似地，SSL用于与代理进行通信，以保护它们随请求发送的cookie值。
For other services, it is likely that the entity from which requests appear to originate will be charged for the service to be rendered. This has implications in terms of authentication and authorization of service provision at the time of the request. It is necessary for the service to be authorized in such a way that non-repudiation is ensured; this is likely to mean that a certificate of identity be provided from the person making the request, and that this can be tied in with a financial account that that person has with the service provider. The certificate can then be stored as part of the billing record. While the process of electronic commerce is outside of the scope of this work, the mechanism by which a request for confirmation of identity is passed out to the requesting user and is delivered back to the service logic must be considered.
对于其他服务，可能会向发出请求的实体收取提供服务的费用。这对请求时服务提供的身份验证和授权具有影响。必须以确保不可抵赖性的方式授权服务；这可能意味着提出请求的人必须提供身份证明，并且这可以与该人在服务提供商处的金融账户挂钩。然后可以将证书存储为帐单记录的一部分。虽然电子商务过程不在本工作范围内，但必须考虑将身份确认请求传递给请求用户并传递回服务逻辑的机制。
When changing from a "pure" IN/PSTN system to one supporting requests via the Internet, the differences in the way that clients interacted with the services meant that the service logic had to be redesigned. It was realized that maintaining the state of a service during its processing was going to be a problem; this problem was side-stepped by re-engineering the services as form processors, allowing them to deal with fully specified requests as a single (Web) transaction. In addition, a "normal" Web Server was used to deliver the forms to the users. This is a change from the IN system, where the equivalent of the form (the prompts) were sent in sequence as part of the same service process.
当从一个“纯”的IN/PSTN系统转变为一个通过互联网支持请求的系统时，客户端与服务交互方式的差异意味着必须重新设计服务逻辑。人们意识到，在服务处理过程中维护服务的状态将是一个问题；通过将服务重新设计为表单处理器，允许它们作为单个（Web）事务处理完全指定的请求，从而避免了这个问题。此外，还使用“普通”Web服务器将表单交付给用户。这是对IN系统的一个更改，在IN系统中，表单（提示）的等价物作为同一服务流程的一部分按顺序发送。
The Call Center features provided suited this change. However, this may not be the case for other IN services. It is quite common for services to be designed such that the user is prompted for a response, and the service continues dependent on this response. The Web form presents all of the options at once, so this kind of variant prompt/collect sequence is not possible. From this, it is difficult to see how an IN service could be reused without some degree of modification.
提供的呼叫中心功能适合此更改。但是，其他IN服务可能并非如此。服务的设计通常会提示用户进行响应，并且服务继续依赖于此响应。Web表单一次显示所有选项，因此这种变体提示/收集序列是不可能的。从这一点上，很难看出在不进行一定程度的修改的情况下如何重用服务中的服务。
An intermediate "gateway" system was provided to "cocoon" the service logic as far as possible from the details of the components with which it was working. Where needed, this unit translated calls from the service logic into commands that operated with the Internet (and the Web Server that acted as the interface). Our experience was that an SCP could be "spoofed" into thinking that it was operating with other IN components in the normal way. Within the limits of the service used, this proved simpler than was originally expected.
提供了一个中间“网关”系统，以尽可能地将服务逻辑从与之工作的组件的细节中“封装”出来。在需要时，该单元将来自服务逻辑的调用转换为通过Internet（以及充当接口的Web服务器）操作的命令。我们的经验是，SCP可能会被“欺骗”，以为它正在以正常方式与其他IN组件一起运行。在所使用的服务范围内，这比最初预期的要简单。
Selecting this simple approach still allows a considerable range of services to be provided while maintaining any investment in existing IN systems. Modification of existing IN service logic was also easier than feared. All of the services examined provided announcements at the end of the service transaction, and this could be used to trigger a Web response to be sent back to the requesting Internet user. The changes to the Call Center service logic turned out to be minor; it took as long to analyze the service and see how it could be arranged as a sequence of "form processing" transactions as it did to make the changes to the service logic.
选择这种简单的方法仍然可以提供相当多的服务，同时保持对现有系统的任何投资。修改现有的服务内逻辑也比担心的要容易。所检查的所有服务都在服务事务结束时提供公告，这可用于触发将发送回请求Internet用户的Web响应。呼叫中心服务逻辑的变化结果很小；分析服务并查看如何将其安排为一系列“表单处理”事务，就像对服务逻辑进行更改一样，需要花费很长的时间。
In the Siemens Web Call Center, the "Internet Intelligent Peripheral" with which the service logic communicated was running as a separate program on the same node. Where more complex behavior is required of it (such as conversion of text to speech data and interface with the PSTN) then it would almost certainly be on a separate node. If data is transferred from the Internet in such a scheme, any intermediate gateway would be involved in relaying the data to this node.
在西门子网络呼叫中心，服务逻辑与之通信的“互联网智能外围设备”作为单独的程序在同一节点上运行。如果需要更复杂的行为（如将文本转换为语音数据以及与PSTN的接口），则几乎可以肯定它将位于单独的节点上。如果数据以这种方式从互联网传输，任何中间网关都将参与将数据中继到此节点。
AT&T developed a framework for controlling voice and voice-band data (e.g., fax) and for providing PINT services. Key to the framework is CallBroker, a logical entity that acts on behalf of a user to set up sessions and make requests for PSTN resources. The sessions typically include initiation of calls between two or more end points specified by the user. In addition to its interactions with the PSTN for call setup, the CallBroker is responsible for other functions, when necessary, such as authentication and usage recording.
AT&T开发了一个用于控制语音和声带数据（如传真）以及提供PINT服务的框架。该框架的关键是CallBroker，它是一个逻辑实体，代表用户设置会话并请求PSTN资源。会话通常包括在用户指定的两个或多个端点之间发起呼叫。除了与PSTN交互以进行呼叫设置外，CallBroker还负责其他必要的功能，如身份验证和使用情况记录。
This section briefly discusses the protocol at the two interfaces that need to be defined and the corresponding APIs to provide the above services. The two interfaces are (1) the one between the CallBroker (or Web Server) and the Service Control Function in the Service Node in the PSTN and (2) the one between the IP client and the CallBroker. The latter interface, in particular, will enable service providers to extend the architecture defined here to serve as a platform for other advanced/value-added services (to be identified later). In addition, the view taken here is that the IP client is more general, and implements a protocol for communication with the CallBroker that allows full two-way communications. For example, this is required for the cases where a called party hangs up and an indication may be necessary to be given to the IP Client about this status/progress. This is also necessary when conferencing to give an indication/status of various parties joining the call.
本节简要讨论需要定义的两个接口上的协议以及提供上述服务的相应API。这两个接口是（1）呼叫代理（或Web服务器）和PSTN中服务节点中的服务控制功能之间的接口，以及（2）IP客户端和呼叫代理之间的接口。特别是后一个接口，将使服务提供商能够扩展此处定义的体系结构，作为其他高级/增值服务（稍后确定）的平台。此外，这里的观点是，IP客户端更通用，并且实现了一个与CallBroker通信的协议，该协议允许完全双向通信。例如，在被叫方挂断并且可能需要向IP客户端指示该状态/进度的情况下，这是必需的。这在会议时也是必要的，以给出加入呼叫的各方的指示/状态。
A high level architecture depicting various logical entities and the Interfaces among these logical Entities and the IP Client is shown in Figure 12.
图12显示了描述各种逻辑实体以及这些逻辑实体与IP客户端之间的接口的高级体系结构。
________________
/
1 _____ / 2 _____
/|________________| |________| | PSTN
|____| \ |____|
Call \ / SCF\
Broker \ / SN \
\_____________
/ \
/ \
/ \
__ __
/\ /\
________________
/
1 _____ / 2 _____
/|________________| |________| | PSTN
|____| \ |____|
Call \ / SCF\
Broker \ / SN \
\_____________
/ \
/ \
/ \
__ __
/\ /\
Calling Participant Party (Called Party)
主叫参与方（被叫方）
Figure 12: The CallBroker Architecture
图12:CallBroker体系结构
The CallBroker, in addition to the initiation and control of calls on behalf of the user, performs additional functions. These functions include authenticating the IP Client, usage recording, and management of the session for the IP Client for the telephony call. The notion of the session requires that a client state machine be maintained in the CallBroker. This also helps in notifying the IP Client about the status/progress of the requests generated from the IP Client.
CallBroker除了代表用户发起和控制调用外，还执行其他功能。这些功能包括验证IP客户端、使用情况记录和管理IP客户端的电话呼叫会话。会话的概念要求在CallBroker中维护客户端状态机。这也有助于通知IP客户端从IP客户端生成的请求的状态/进度。
From the perspective of the IP Client, the logical entities needed for the above functions are within the CallBroker and are as shown in Figure 13 below. These correspond to the functions already discussed: Usage Recording Function, Session Management Function, Voice Bridge, and the Authentication Function. The fact that some of these functions may be physically separate from the CallBroker (such as the Voice Bridge being in the PSTN) is not inconsistent with the general view adopted here. Thus, the CallBroker Model mediates requests for network services and enables us to define various value added services in the future.
从IP客户端的角度来看，上述功能所需的逻辑实体位于CallBroker中，如下图13所示。这些功能与前面讨论的功能相对应：使用记录功能、会话管理功能、语音桥和身份验证功能。这些功能中的一些可能在物理上与CallBroker分离（例如PSTN中的语音网桥），这一事实与本文采用的一般观点并不矛盾。因此，CallBroker模型调解对网络服务的请求，并使我们能够在将来定义各种增值服务。
llllllllllllllll
l l
l Call Broker l Authentication
l Server l Function
l ______ l Interface 2a ______
l | |x x xlx x x x x x x x x | |
l |______|x l |____|
l x x l
l x xl Interface 2b
lSession State lx
l Mnmgt. x l x Usage Recording
l Function l x Function
l _______ x l x ______
l | | l x x x | |
l |_____| xl |____|
llllllllllllllll
x
x Interface 2c
x
_______
| |
|_____|
llllllllllllllll
l l
l Call Broker l Authentication
l Server l Function
l ______ l Interface 2a ______
l | |x x xlx x x x x x x x x | |
l |______|x l |____|
l x x l
l x xl Interface 2b
lSession State lx
l Mnmgt. x l x Usage Recording
l Function l x Function
l _______ x l x ______
l | | l x x x | |
l |_____| xl |____|
llllllllllllllll
x
x Interface 2c
x
_______
| |
|_____|
Bridge
桥
Figure 13: Functional Entities in the Call Broker
图13：呼叫代理中的功能实体
Various interfaces (i.e., 2a, 2b, 2c in Figure 13) between different functional entities in the CallBroker may also be standardized. The Session State Management Function may be physically realized as part of the CallBroker Server.
CallBroker中不同功能实体之间的各种接口（即图13中的2a、2b、2c）也可以标准化。会话状态管理功能可以作为CallBroker服务器的一部分物理实现。
Communication on the IP Client to CallBroker Interface (Interface 1 in Figure 12) is a simple ASCII based protocol running directly on TCP. The messages on this interface are primarily requests from the client to the CallBroker, responses from the CallBroker to the IP client responding to the requests and unsolicited events from the CallBroker to the IP client. Since the communication is not strictly transaction oriented, traditional encapsulation protocols like HTTP cannot be used. There has been some ongoing work attempting to use multiple concurrent HTTP POST requests to support event delivery but, without too much difficulty, the ASCII protocol specified here can easily be mapped to the POST payload of the HTTP protocol.
IP客户端到CallBroker接口（图12中的接口1）的通信是一个简单的基于ASCII的协议，直接在TCP上运行。此接口上的消息主要是客户端对CallBroker的请求、CallBroker对IP客户端对请求的响应以及CallBroker对IP客户端的未经请求的事件。由于通信不是严格面向事务的，因此无法使用HTTP等传统封装协议。有一些正在进行的工作试图使用多个并发HTTP POST请求来支持事件传递，但是，这里指定的ASCII协议可以轻松地映射到HTTP协议的POST有效负载，这没有太大的困难。
Basic Format
基本格式
The basic format of the protocol is as follows:
协议的基本格式如下：
[header]<<LF>
<<LF>
[body]<<LF>
<<LF>
<<LF>
[header]<<LF>
<<LF>
[body]<<LF>
<<LF>
<<LF>
The header and body of the protocol are separated by 2 line feed characters. The format of the header and the body is described below. Line feed characters in the header or body will be escaped using simple URL encoding.
协议的头和正文由两个换行字符分隔。标题和正文的格式如下所述。标题或正文中的换行符将使用简单的URL编码进行转义。
Header
标题
[session-id | 0]<<LF>
[message-id]<<LF>
[version-info]<<LF>
[session-id | 0]<<LF>
[message-id]<<LF>
[version-info]<<LF>
All CallBroker transactions are identified by sessions. A session does not necessarily correspond one-to-one to a TCP session. If the IP client is attempting to initiate a new session with the CallBroker the session-id field is populated with '0' to indicate session creation request. Every session request needs to be accompanied by sufficient information regarding authentication for the CallBroker to create the session.
所有CallBroker事务都由会话标识。会话不一定与TCP会话一一对应。如果IP客户端正试图启动与CallBroker的新会话，则会话id字段将填充“0”，以指示会话创建请求。每个会话请求都需要有足够的关于身份验证的信息，以便CallBroker创建会话。
Message-id represents the operation of the message.
消息id表示消息的操作。
Version-info contains optional version information of the protocol. This is to aid possible version mismatch detection and graceful error recovery.
版本信息包含协议的可选版本信息。这有助于可能的版本不匹配检测和良好的错误恢复。
Body
身体
The body of the protocol messages consists of name value pairs. These name-value pairs are interpreted with reference to the message-id which signifies the operation to be performed by the CallBroker.
协议消息体由名称-值对组成。这些名称-值对参照消息id进行解释，消息id表示CallBroker要执行的操作。
The APIs of the CallBroker exposed to the IP client are distinct and different from the APIs that the CallBroker uses from the different supporting subsystems including the authentication subsystem and the usage recording subsystem. The IP client APIs enable clients to effectively control voice conferencing.
向IP客户机公开的CallBroker的API与CallBroker从不同的支持子系统（包括身份验证子系统和使用情况记录子系统）使用的API不同。IP客户端API使客户端能够有效地控制语音会议。
The Voice Bridge Control API is used by CallBroker applications to access voice bridging functionality. The API distinguishes between sessions and calls. Calls represent actual voice calls placed from/to the voice bridge. These calls can be grouped together in sessions. All the calls that belong to a session are bridged. Calls have a significance outside the scope of sessions. Every call can be associated with multiple sessions with different weights at the same time. The advantage of this approach is the ability to support concepts like whispering in a conference call. Calls can also be dropped from a conference session and bridged together in a new session to give the notion of a sub-conference. These calls can later be re-added to the main conference session.
CallBroker应用程序使用语音桥接控制API访问语音桥接功能。API区分会话和调用。呼叫表示从语音网桥发出/接到语音网桥的实际语音呼叫。这些调用可以在会话中分组在一起。属于会话的所有调用都将桥接。呼叫的重要性超出会话的范围。每个呼叫可以同时与具有不同权重的多个会话相关联。这种方法的优点是能够支持电话会议中的耳语等概念。电话也可以从会议会话中断开，并在新会话中桥接在一起，形成分会议的概念。这些呼叫稍后可以重新添加到主会议会话中。
The Simple Computer Telephony Protocol (SCTP) is a third party call control protocol and as such does not comply with the PINT charter. SCTP is described in this section to show how PINT services could be implemented using SCTP, and where SCTP fits into the PINT architecture.
简单计算机电话协议（SCTP）是第三方呼叫控制协议，因此不符合PINT章程。本节介绍了SCTP，以说明如何使用SCTP实现PINT服务，以及SCTP在PINT体系结构中的适用性。
In addition to third party call control, SCTP also provides subscriber (i.e., user) feature management (e.g., allows a user to set do not disturb, call forwarding parameters), and subscriber monitoring of terminal, line and address status. SCTP is strictly client/server-based. It has no provisions for peer to peer communications. SCTP runs as a TCP application protocol. It is ASCII-based and uses sockets. The SCTP Server is usually connected to a switch via a CTI (Computer-Telephony Integration) connection. Because of this, feature interactions are limited to those within the context of a single call, and not between PSTN services. The SCTP Server within a PINT Gateway could also be connected to an SN, or an SCP. See figures below. SCTP does NOT carry media.
除第三方呼叫控制外，SCTP还提供用户（即用户）功能管理（例如，允许用户设置请勿打扰、呼叫转接参数），以及用户对终端、线路和地址状态的监控。SCTP严格基于客户端/服务器。它没有对等通信的规定。SCTP作为TCP应用程序协议运行。它基于ASCII并使用套接字。SCTP服务器通常通过CTI（计算机电话集成）连接连接到交换机。因此，功能交互仅限于单个呼叫上下文中的交互，而不限于PSTN服务之间的交互。PINT网关中的SCTP服务器也可以连接到SN或SCP。见下图。SCTP不携带介质。
SCTP Client as Part of a Web Server
作为Web服务器一部分的SCTP客户端
+------+ +--------+ +--------+ +------+
| | | | SCTP | | | |
| |----| |-------| |----| |
| | | | | | | |
+------+ +--------+ +--------+ +------+
User's PC Web Server/ PINT Gateway SN/SCP/Switch
CGI
+------+ +--------+ +--------+ +------+
| | | | SCTP | | | |
| |----| |-------| |----| |
| | | | | | | |
+------+ +--------+ +--------+ +------+
User's PC Web Server/ PINT Gateway SN/SCP/Switch
CGI
Figure 14: SCTP Client as Part of a Web Server
图14:SCTP客户端作为Web服务器的一部分
In this architecture, the SCTP Client is embedded in the Web Server. It is there for the specific purpose of initiating calls to the PSTN based on user requests. The SCTP Server is within the PINT Gateway. We go through the classic PINT examples:
在此体系结构中，SCTP客户端嵌入在Web服务器中。它专门用于根据用户请求发起PSTN呼叫。SCTP服务器位于PINT网关内。我们将介绍经典的品脱示例：
Click-to-dial-back: The SCTP Client issues an SCTP MakeCall to the SCTP Server with the calling number supplied by Web page, and called number supplied by the user.
单击回拨：SCTP客户端向SCTP服务器发出SCTP MakeCall，呼叫号码由网页提供，被叫号码由用户提供。
Click-to-fax-back: SCTP Client issues an SCTP MakeCall to the SCTP Server with called number set to user's fax machine, and calling number set to Web Server's fax machine, and treatment set to the URI for the file to be faxed. The SCTP Server takes the file and feeds it into the call just as a fax machine would.
单击以传真回：SCTP客户端向SCTP服务器发出SCTP MakeCall，被叫号码设置为用户的传真机，主叫号码设置为Web服务器的传真机，处理设置为要传真的文件的URI。SCTP服务器接收文件并将其输入呼叫，就像传真机一样。
Click-to-fax: SCTP Client issues an SCTP MakeCall with calling number set to user's fax machine, and called number set to Web Server's fax machine. How the file is supplied to the user's fax machine is outside the scope of SCTP.
单击以传真：SCTP客户端发出SCTP MakeCall，呼叫号码设置为用户的传真机，被叫号码设置为Web服务器的传真机。如何将文件提供给用户的传真机超出了SCTP的范围。
Voice-access-to-content: SCTP Client issues an SCTP MakeCall with called number set to user's telephone number, and calling number set to Web Server and treatment set to a URI for the file of the particular Web page to be read to the called number. The SCTP Server takes care of the file to voice conversion and this is fed into the call as if it were voice.
对内容的语音访问：SCTP客户端发出SCTP MakeCall，被叫号码设置为用户的电话号码，主叫号码设置为Web服务器，处理设置为URI，以便将特定网页的文件读取到被叫号码。SCTP服务器负责文件到语音的转换，并将其作为语音输入到呼叫中。
In all of the above cases, the SCTP Client can generate a variety of different Web pages to send to the Web Server via CGI (Common Gateway Interface). The content of these pages is based on the call completion status of the CallMake SCTP action.
在上述所有情况下，SCTP客户端可以生成各种不同的网页，通过CGI（公共网关接口）发送到Web服务器。这些页面的内容基于CallMake SCTP操作的调用完成状态。
SCTP Client Running on the User's PC
在用户PC上运行的SCTP客户端
+------+
HTML | | INTERNET
+-----+ /--------------| |
| |---/ +------+
| | Web Server
| |---\
+-----+ \
User's PC \ SCTP +------+ +------+
\------------| |-------| | PSTN
| | | |
+------+ +------+
PINT Gateway SN/SCP/Switch
+------+
HTML | | INTERNET
+-----+ /--------------| |
| |---/ +------+
| | Web Server
| |---\
+-----+ \
User's PC \ SCTP +------+ +------+
\------------| |-------| | PSTN
| | | |
+------+ +------+
PINT Gateway SN/SCP/Switch
Figure 15: SCTP Client Running on the User's PC
图15：在用户PC上运行的SCTP客户端
In this architecture, the user has an SCTP Client co-located with it. If the user is using the telephone line for connection to a Web Server and there is an incoming call, then the SCTP Server in the PINT Gateway will post this event to the SCTP Client. A window will pop up on the user's screen with options available to the user for handling of the incoming call. The user can choose to take the call, send it to voice mail, or send it to another number.
在这种体系结构中，用户有一个与之共存的SCTP客户端。如果用户使用电话线连接到Web服务器，并且有来电，则PINT网关中的SCTP服务器将向SCTP客户端发送此事件。用户屏幕上将弹出一个窗口，其中包含可供用户处理来电的选项。用户可以选择接听电话、将其发送到语音信箱或发送到其他号码。
For the Fax back service, for example, if the user had a separate fax machine from his or her PC, then the SCTP Server would tell the SCTP Client there is an incoming fax. The user would end or suspend his or her Internet connection, the fax would come in, and the user could then resume the Internet connection.
例如，对于传真回服务，如果用户的PC上有一台单独的传真机，则SCTP服务器会告诉SCTP客户端有一个传入传真。用户将结束或暂停其互联网连接，传真将进入，然后用户可以恢复互联网连接。
SIP, the Session Initiation Protocol, is a simple signaling protocol for Internet conferencing and telephony. It is currently under development within the IETF MMUSIC (Multiparty Multimedia Session Control) Working Group.
会话启动协议SIP是一种用于Internet会议和电话的简单信令协议。它目前正在IETF MMUSIC（多方多媒体会话控制）工作组内开发。
SIP provides the necessary mechanisms to support the following services:
SIP提供了必要的机制来支持以下服务：
- call forwarding, including the equivalent of 700-, 800- and 900- type calls; - call-forwarding no answer;
- 呼叫转移，包括相当于700、800和900类型的呼叫；-呼叫转移无应答；
- call-forwarding busy; - call-forwarding unconditional; - other address-translation services; - callee and calling "numbers" delivery, where the numbers can be of any (preferably unique) naming scheme; - personal mobility, i.e., the ability to reach a called party under a single, location-independent address, even when the user changes terminals; - terminal-type negotiation and selection: a caller can be given a choice of how to reach a party, e.g., via Internet telephony, mobile, phone, and an answering service; - caller and callee authentication; - blind and supervised call transfer; - user location; and - invitation to multicast conferences.
- 呼叫转接忙；-无条件呼叫转移；-其他地址翻译服务；-被叫方和主叫方“号码”传递，其中号码可以是任何（最好是唯一的）命名方案；-个人移动性，即即使用户更换终端，也能在单个独立于位置的地址下到达被叫方的能力；-终端类型协商和选择：呼叫方可以选择如何联系一方，例如通过互联网电话、手机、电话和应答服务；-调用方和被调用方身份验证；-盲呼叫转移和监督呼叫转移；-用户位置；和-邀请参加多播会议。
Extensions of SIP to allow third-party signaling (e.g., for click-to-dial-back services, fully meshed conferences and connections to Multipoint Control Units (MCUs), as well as mixed modes and the transition between those) have been specified.
已经指定了允许第三方信令的SIP扩展（例如，点击回拨服务、全网状会议和到多点控制单元（MCU）的连接，以及混合模式和这些模式之间的转换）。
SIP addresses (URLs) can be embedded in Web pages. SIP is addressing-neutral, with addresses expressed as URLs of various types such as SIP, H.323 or telephone (E.164). A purely representational example of a SIP URL might be sip:+12125551212@foo.example.com, where foo.example.com is the host serving as a gateway into the PSTN.
SIP地址（URL）可以嵌入到网页中。SIP是寻址中性的，地址表示为各种类型的URL，如SIP、H.323或电话（E.164）。SIP URL的纯粹代表性示例可能是SIP：+12125551212@foo.example.com，其中foo.example.com是作为PSTN网关的主机。
SIP is independent of the packet layer and only requires an unreliable datagram service, as it provides its own reliability mechanism. While SIP typically is used over UDP or TCP, it could, without technical changes, be run over IPX, or carrier pigeons, ATM AAL5 or X.25, in rough order of desirability.
SIP独立于数据包层，只需要不可靠的数据报服务，因为它提供了自己的可靠性机制。虽然SIP通常在UDP或TCP上使用，但在没有技术更改的情况下，它可以按照大致的期望顺序在IPX或信鸽、ATM AAL5或X.25上运行。
SIP can set up calls "out-of-band". For example, while the SIP protocol exchanges use IP, plus UDP or TCP, the actual data transport can take place via the PSTN. This feature makes it possible to use SIP to control a PBX or send requests to a Service Control Point. The PINT services make use of this flexibility.
SIP可以设置“带外”呼叫。例如，当SIP协议交换使用IP加上UDP或TCP时，实际的数据传输可以通过PSTN进行。此功能使使用SIP控制PBX或向服务控制点发送请求成为可能。PINT服务利用了这种灵活性。
SIP is a textual client-server protocol, similar in syntax to HTTP and RTSP. Requests consist of a method (INVITE, BYE, ACK, or REGISTER), a list of parameter-value pairs describing the request and an optional request body. Parameters include the origin and destination of the call and a unique call identifier. They may indicate the caller's organization as well as the call's subject and priority. The request body contains a description of the call to be
SIP是一种文本客户端-服务器协议，在语法上类似于HTTP和RTSP。请求包括一个方法（INVITE、BYE、ACK或REGISTER）、一个描述请求的参数-值对列表和一个可选的请求主体。参数包括呼叫的来源和目的地以及唯一的呼叫标识符。它们可以指示呼叫方的组织以及呼叫的主题和优先级。请求正文包含要执行的调用的描述
established or the conference to be joined. The description format is not prescribed by SIP; SDP is one possibility being standardized within the IETF. For the purposes of providing PINT services, an additional phone number address format is to be added to SDP.
已建立或将要加入的会议。SIP未规定描述格式；SDP是IETF中标准化的一种可能性。为了提供PINT服务，SDP中将添加一个附加的电话号码地址格式。
Responses indicate whether a request is still being processed, was successful, can possibly be satisfied by another node or failed. When a call is redirected, the response indicates the name of the node to be tried. Unsuccessful calls may also return a better time to try again.
响应指示请求是否仍在处理中、是否成功、是否可能由其他节点满足或失败。当呼叫被重定向时，响应指示要尝试的节点的名称。不成功的呼叫也可能返回更好的时间重试。
In a typical successful call, the caller sends an INVITE request to the callee. The callee accepts the call by returning a response code to the callee, which then confirms the receipt of that acceptance with an ACK request. Either side can terminate the call by sending a BYE request.
在典型的成功呼叫中，呼叫者向被呼叫者发送INVITE请求。被调用者通过向被调用者返回响应代码来接受呼叫，然后被调用者通过ACK请求确认接收到该接受。任何一方都可以通过发送BYE请求来终止呼叫。
Requests can be authenticated using standard HTTP password and challenge-response mechanisms. Requests and responses may also be signed and encrypted.
可以使用标准HTTP密码和质询响应机制对请求进行身份验证。请求和响应也可以签名和加密。
SIP distinguishes three kinds of entities:
SIP区分了三种实体：
User agents receive and initiate calls and may forward the call.
用户代理接收和发起呼叫，并可以转发呼叫。
A proxy server is an intermediary program that acts as both a server and a client for the purpose of making requests on behalf of other clients. Requests are serviced internally or by passing them on, possibly after translation, to other servers. A proxy must interpret, and, if necessary, rewrite a request message before forwarding it. A proxy server may, for example, locate a user and then attempt one or more possible network addresses.
代理服务器是一种中介程序，它同时充当服务器和客户端，以代表其他客户端发出请求。请求可以在内部提供服务，也可以在转换后传递给其他服务器。代理必须在转发请求消息之前对其进行解释，并在必要时重写请求消息。例如，代理服务器可以定位用户，然后尝试一个或多个可能的网络地址。
Redirect server accepts a SIP request, maps the address into zero or more new addresses and returns these addresses to the client. Unlike a proxy server, it does not initiate its own SIP request. Unlike a user agent server, it does not accept calls.
重定向服务器接受SIP请求，将地址映射为零个或多个新地址，并将这些地址返回给客户端。与代理服务器不同，它不会启动自己的SIP请求。与用户代理服务器不同，它不接受调用。
Proxy and redirect servers may make use of location servers that determine the current likely location of the callee.
代理服务器和重定向服务器可以使用位置服务器来确定被调用方的当前可能位置。
A PSTN gateway initiates phone calls between two parties. This may be a server that sends requests to an SCP in an IN environment or it may be a CTI-controlled PBX.
PSTN网关在双方之间发起电话呼叫。这可能是向in环境中的SCP发送请求的服务器，也可能是CTI控制的PBX。
A SIP call may traverse one or more proxy servers.
SIP调用可以遍历一个或多个代理服务器。
The servers that control a PBX or an SCP act as user agents. A Web server may also act as a SIP user agent.
控制PBX或SCP的服务器充当用户代理。Web服务器还可以充当SIP用户代理。
The SIP for PINT specification provides details on how to use SIP to initiate phone calls between two PSTN end points. (SIP can also initiate calls between Internet end points and between an Internet and PSTN end point, but this is beyond the scope of this document.)
SIP for PINT规范提供了有关如何使用SIP在两个PSTN端点之间发起电话呼叫的详细信息。（SIP还可以在Internet端点之间以及Internet和PSTN端点之间发起呼叫，但这超出了本文档的范围。）
It should be noted that the SIP client for initiating such phone calls can be either at the user's location (his/her workstation) or can be a Web server that calls up a SIP client via a CGI program. There is no difference in operation or functionality, except that the owner of the Web server may be legally responsible for the calls made.
应当注意，用于发起此类电话呼叫的SIP客户端可以位于用户的位置（他/她的工作站），或者可以是通过CGI程序呼叫SIP客户端的Web服务器。除了Web服务器的所有者可能对所做的调用承担法律责任外，操作或功能没有区别。
A SIP client needs to convey two addresses to the PSTN gateway: the party making the call and the party to be called. (The party to be billed also needs to be identified; this can either be done by a SIP header or by having the server look up the appropriate party based on the two parties. This aspect is for further study.)
SIP客户端需要向PSTN网关传送两个地址：呼叫方和被呼叫方。（还需要确定要计费的一方；这可以通过SIP头完成，也可以让服务器根据双方查找适当的一方。这方面有待进一步研究。）
Described below are three ways these addresses can be conveyed in SIP. In the example, the address of party A is +1-212-555-1234 and that of party B is +1-415-555-1200. (The URL types in this and other examples are representational; they may but do not have to exist.)
下面介绍了在SIP中传输这些地址的三种方式。本例中，甲方地址为+1-212-555-1234，乙方地址为+1-415-555-1200。（本示例和其他示例中的URL类型具有代表性；它们可能存在，但不一定存在。）
(1) The two PSTN addresses are contained in the To header (and request-URI) and an Also header. For example:
(1) 这两个PSTN地址包含在To报头（和请求URI）和ALL报头中。例如：
INVITE sip:+1-212-555-1234@pbx.example.com SIP/2.0
To: phone:1-212-555-1234
From: sip:j.doe@example.com
Content-type: application/sdp
Call-ID: 19970721T135107.25.181@foo.bar.com
Also: phone:+1-415-555-1200
INVITE sip:+1-212-555-1234@pbx.example.com SIP/2.0
To: phone:1-212-555-1234
From: sip:j.doe@example.com
Content-type: application/sdp
Call-ID: 19970721T135107.25.181@foo.bar.com
Also: phone:+1-415-555-1200
v=0
o=user1 53655765 2353687637 IN IP4 128.3.4.5
c=PSTN E.164 +1-415-555-1200
t=0 0
m=audio 0 RTP/AVP 0
v=0
o=user1 53655765 2353687637 IN IP4 128.3.4.5
c=PSTN E.164 +1-415-555-1200
t=0 0
m=audio 0 RTP/AVP 0
In that case, the gateway first connects to party A and then party B, but without waiting for A to accept the call before calling B.
在这种情况下，网关首先连接到甲方，然后连接到乙方，但在呼叫B之前不等待A接受呼叫。
(2) Parties A and B are indicated by separate invitations. This allows the gateway to make sure that party A is indeed available before calling party B. After calling party A, the gateway could play an announcement indicating that the call is being connected using, for example, RTSP with appropriate Conference header indicating the call.
(2) 甲、乙双方分别发出邀请。这允许网关在呼叫乙方之前确保甲方确实可用。在呼叫甲方之后，网关可以播放一条公告，指示呼叫正在连接，例如使用RTSP（带有指示呼叫的适当会议标头）进行连接。
INVITE sip:+1-212-555-1234@pbx.example.com SIP/2.0 To: phone:1-212-555-1234 From: sip:j.doe@example.com Content-type: application/sdp Call-ID: 19970721T135107.25.181@foo.bar.com ... INVITE sip:+1-415-555-1200@pbx.example.com SIP/2.0 To: phone:+1-415-555-1200 From: sip:j.doe@example.com Content-type: application/sdp Call-ID: 19970721T135107.25.181@foo.bar.com ...
邀请sip：+1-212-555-1234@pbx.example.comSIP/2.0收件人：电话：1-212-555-1234发件人：SIP:j。doe@example.com内容类型：应用程序/sdp调用ID:19970721T135107.25。181@foo.bar.com ... 邀请sip：+1-415-555-1200@pbx.example.comSIP/2.0收件人：电话：+1-415-555-1200发件人：SIP:j。doe@example.com内容类型：应用程序/sdp调用ID:19970721T135107.25。181@foo.bar.com ...
(3) The two PSTN addresses are conveyed in the To header of the SIP request and the address in the SDP media description. Thus, a request may look as follows:
(3) 这两个PSTN地址在SIP请求的To报头和SDP媒体描述中传输。因此，请求可能如下所示：
INVITE sip:+1-212-555-1234@pbx.example.com SIP/2.0
To: phone:1-212-555-1234
From: sip:j.doe@example.com
Content-type: application/sdp
Call-ID: 19970721T135107.25.181@foo.bar.com
INVITE sip:+1-212-555-1234@pbx.example.com SIP/2.0
To: phone:1-212-555-1234
From: sip:j.doe@example.com
Content-type: application/sdp
Call-ID: 19970721T135107.25.181@foo.bar.com
v=0
o=user1 53655765 2353687637 IN IP4 128.3.4.5
c=PSTN E.164 +1-415-555-1200
t=0 0
m=audio 0 RTP/AVP 0
v=0
o=user1 53655765 2353687637 IN IP4 128.3.4.5
c=PSTN E.164 +1-415-555-1200
t=0 0
m=audio 0 RTP/AVP 0
Here, pbx.example.com is the name of the PSTN gateway; the call will be established between 1-212-555-1234 and +1-415-555-1200.
这里，pbx.example.com是PSTN网关的名称；呼叫将在1-212-555-1234和+1-415-555-1200之间建立。
Users can be added to an existing call by method (1) or (2).
可以通过方法（1）或（2）将用户添加到现有调用中。
Inter-networking of the Internet and PSTN necessitates the introduction of new interfaces (e.g., the A, B and E interfaces in Figure 6). To ensure that their use does not put the networks, in particular the PSTN, at additional security risk, these interfaces need to be designed with proper security considerations. Sections
互联网和PSTN的互连需要引入新的接口（如图6中的A、B和e接口）。为确保其使用不会使网络（尤其是PSTN）面临额外的安全风险，这些接口的设计需要考虑到适当的安全因素。小节
5.1.5 and 5.2.2.7 describe how two of the pre-PINT implementations, the Lucent and Siemens systems, handle the security aspect, respectively.
5.1.5 和5.2.2.7分别描述了朗讯和西门子系统这两个PINT之前的实施如何处理安全方面的问题。
Worth noting are the security requirements suggested by pre-PINT experiences. They are:
值得注意的是品脱前的经验所提出的安全要求。他们是：
+Peer entity authentication to allow a communicating entity to prove its identity to another in the network (e.g., the requesting IP-host to the PINT gateway, and the PINT gateway to the PSTN node providing the service control function).
+对等实体认证，允许通信实体向网络中的另一个实体证明其身份（例如，向PINT网关发出请求的IP主机，以及向提供服务控制功能的PSTN节点发出请求的PINT网关）。
+Authorization and access control to verify if a network entity (e.g., the requesting IP-host) is allowed to use a network resource (e.g., requesting services from the PINT gateway).
+验证网络实体（例如，请求IP主机）是否允许使用网络资源（例如，从PINT网关请求服务）的授权和访问控制。
+Non-repudiation to account for all operations in case of doubt or dispute.
+不可抵赖性，在出现疑问或争议时，对所有操作负责。
+Confidentiality to avoid disclosure of information (e.g., the end user profile information and data) without the permission of its owner.
+保密性，以避免未经所有者许可披露信息（例如，最终用户档案信息和数据）。
In the course of the PINT interface development, additional requirements are likely to arise. It is imperative that the resultant interfaces include specific means to meet all the security requirements.
在PINT接口开发过程中，可能会产生额外的需求。结果接口必须包括满足所有安全要求的特定方法。
This document has provided the information relevant to the development of inter-networking interfaces between the PSTN and Internet for supporting PINT services. Specifically, it addressed technologies, architectures, and several existing pre-PINT implementations of the arrangements through which Internet applications can request and enrich PSTN telecommunications services. One key observation is that the pre-PINT implementations, being developed independently, do not inter-operate. It is a task of the PINT Working Group to define the inter-networking interfaces that will support inter-operation of the future implementations of PINT services.
本文件提供了PSTN和Internet之间用于支持PINT服务的互联接口开发的相关信息。具体而言，它涉及技术、体系结构和几种现有的协议前实现，通过这些协议，互联网应用程序可以请求和丰富PSTN电信服务。一个关键的观察结果是，独立开发的pre-PINT实现不会相互操作。PINT工作组的任务是定义将支持未来PINT服务实现的互操作的网络间接口。
The authors would like to acknowledge Scott Bradner, Igor Faynberg, Dave Oran, Scott Petrack, Allyn Romanow for their insightful comments presented to the discussions in the PINT Working Group that lead to the creation of this document.
作者要感谢Scott Bradner、Igor Faynberg、Dave Oran、Scott Petrack、Allyn Romanow在品脱工作组讨论中提出的富有洞察力的意见，这些意见导致了本文件的编制。
What is normally considered as "the Telephone Network" consists of a set of interconnected networks. Potentially, each of these networks could be owned by a different Network Operator. The official name for such a network is Public Switched Telecommunications Network (PSTN). A simple PSTN consists of a set of Switches (called Central Offices or Telephone Exchanges) with links interconnecting them to make up the network, along with a set of access connections by which terminals are attached. The PSTN is used to deliver calls between terminals connected to itself or to other PSTNs with which it is interconnected. Calls on the PSTN are circuit switched; that is, a bi-directional connection is made between the calling and called terminals for the duration of the call. In PSTNs the connection is usually carried through the network in digital format occupying a fixed bandwidth; this is usually 56 or 64 Kbps. The overall configuration of the PSTN is shown in Figure 16.
通常被认为是“电话网络”的东西由一组相互连接的网络组成。这些网络中的每一个都可能由不同的网络运营商拥有。这种网络的官方名称是公共交换电信网（PSTN）。简单的PSTN由一组交换机（称为中央局或电话交换机）和一组连接终端的接入连接组成，交换机之间的链路相互连接，构成网络。PSTN用于在连接到自身或与其互连的其他PSTN的终端之间传送呼叫。PSTN上的呼叫是电路交换的；也就是说，在呼叫期间，在主叫终端和被叫终端之间建立双向连接。在PSTNs中，连接通常以数字格式通过网络进行，占用固定带宽；这通常是56或64 Kbps。PSTN的总体配置如图16所示。
/--\
()/\()__
/__\ \ .................................
\ ! ! ! /--\
__ \ [-!-] [-!-] ! ()/\()
\ \ \__[CO ]=========[CO ]==\\ ! ___/__\
[Fax]________[---] [---] \\ [-!-] / __
\\=======[CO ]____/ \ \
[---]________[Fax]
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
/--\
()/\()__
/__\ \ .................................
\ ! ! ! /--\
__ \ [-!-] [-!-] ! ()/\()
\ \ \__[CO ]=========[CO ]==\\ ! ___/__\
[Fax]________[---] [---] \\ [-!-] / __
\\=======[CO ]____/ \ \
[---]________[Fax]
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
Figure 16
图16
Messages are sent between the Switches to make and dissolve connections through the network on demand and to indicate the status of terminals involved in a call; these "signaling" messages are carried over a separate (resilient) data network dedicated to this purpose. This signaling network is also known as the Common Channel Signaling (CCS) or Signaling System Number 7 (or SS7) network after the names of the signaling protocol suite used.
在交换机之间发送消息，根据需要通过网络建立和解除连接，并指示呼叫中涉及的终端的状态；这些“信令”消息通过专用于此目的的单独（弹性）数据网络传输。该信令网络也称为公共信道信令（CCS）或信令系统7号（或SS7）网络，以所用信令协议套件的名称命名。
As yet, the majority of access connections to a PSTN carry analogue signals, with simple (analogue) telephones or Facsimile machines as terminals. Call requests are indicated to the Central Office to which
到目前为止，PSTN的大多数接入连接都带有模拟信号，以简单（模拟）电话或传真机作为终端。呼叫请求被指示给呼叫的中心办公室
a telephone is connected either by a sequence of pulses or tone pairs being sent. Notifications on the status of the request are sent back to the telephone in the form of tones. Indication from a Central Office that a call is being offered to a telephone is arranged by sending an alternating voltage down the access connection which in turn causes the ringer in the telephone to sound. These access lines have a unique address associated with them and can support a single call.
电话通过发送的脉冲序列或音调对连接。请求状态的通知将以铃声的形式发送回电话。从中央办公室发出的向电话提供呼叫的指示是通过向接入连接发送交流电压来安排的，这反过来会使电话中的振铃器发出声音。这些接入线路有一个与之相关联的唯一地址，可以支持单个呼叫。
However, with analogue or digital multi-line connections, or Integrated Service Digital Network (ISDN) Basic or Primary Rate Interfaces (BRI or PRI), several concurrent calls are possible and a set of addresses are associated with them. The new ISDN access connections are designed so that data exchanged with the network is in multiplexed digital form, and there is an individual channel for each of the potential connections, together with a separate channel dedicated to sending and receiving call request and call alert data as well as carrying packet switched user data. These call request and call alert messages act as the equivalent of the pulses or tones that are sent when dialing, and the ringing signal that is sent to a telephone when a call is being made to it.
然而，使用模拟或数字多线连接，或综合业务数字网（ISDN）基本或主要速率接口（BRI或PRI），可以进行多个并发调用，并与一组地址关联。新的ISDN接入连接的设计使与网络交换的数据采用多路数字形式，每个潜在连接都有一个单独的通道，以及一个专用于发送和接收呼叫请求和呼叫警报数据以及承载分组交换用户数据的单独通道。这些呼叫请求和呼叫警报消息相当于拨号时发送的脉冲或铃声，以及通话时发送到电话的铃声信号。
The operation of the call request is fairly simple in most cases and is shown in Figure 17.
调用请求的操作在大多数情况下都相当简单，如图17所示。
/--\
() ()
--____
/++\ \ ................................. /--\
/----\ \ ^ v ! () ()
A \ [-!-] [-!-] ! --
\->[CO ]=========[CO ]==\\ v ->-/ \
[---] [---] \\ [-!-] / /----\
\\=======[CO ]____/ B
[---]
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
CO Central Office (Telephone Exchange)
/--\
() ()
--____
/++\ \ ................................. /--\
/----\ \ ^ v ! () ()
A \ [-!-] [-!-] ! --
\->[CO ]=========[CO ]==\\ v ->-/ \
[---] [---] \\ [-!-] / /----\
\\=======[CO ]____/ B
[---]
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
CO Central Office (Telephone Exchange)
Figure 17
图17
The user presses a sequence of numbers on a telephone handset (labeled A), and the telephone passes a sequence of digits (either as pulses or tone pairs) to the Central Office via the access line. The Central Office contains a processor that will be notified that the user has made a request and the digit string that is the sole parameter of the request. This digit string is taken to be the unique
用户在电话听筒（标有a）上按一系列数字，电话通过接入线将一系列数字（脉冲或音调对）传送到中央办公室。中央办公室包含一个处理器，该处理器将被通知用户已发出请求，并且数字字符串是请求的唯一参数。此数字字符串被认为是唯一的
address of an access line connected either to itself or to another Central Office. There is a hierarchical addressing scheme, so that the digit string can be parsed easily. A call request to a terminal (labeled B) connected to a remote Central Office can be routed by examining the digit string passed; the Central Office will extract the part of the passed address that corresponds to the remote Central Office in question, and can route the request onward, forming an inter-Switch call request and passing it via the signaling network. At the same time it will allocate one of its available transmission channels towards the remote Central Office.
连接到自身或另一个中央办公室的接入线路的地址。有一种分层寻址方案，因此可以轻松解析数字字符串。通过检查传递的数字字符串，可以路由到连接到远程中心办公室的终端（标记为B）的呼叫请求；中心局将提取所传递地址中与所讨论的远程中心局相对应的部分，并可向前路由请求，形成交换机间呼叫请求，并通过信令网络传递该请求。同时，它将向远程中央办公室分配一条可用的传输通道。
This scheme has been used since the 1950s, and suffices for the majority of calls. However, there are a range of other services that can be (and have been) provided, enhancing this basic call processing. Freephone or Premium Rate services (1-800 or 1-900 services) are good examples of the supplementary services that have been introduced. Apart from the important feature that the cost of these calls is varied so that the caller does not pay for a free-phone call, or pays an extra charge for a premium rate call, they have the similarity that the number dialed must be translated to arrive at the "real" address of the destination terminal. They are known as number translation services, and make up the bulk of all supplementary services delivered today.
该方案自20世纪50年代开始使用，满足大多数呼叫的需要。但是，可以（并且已经）提供一系列其他服务，以增强这种基本的呼叫处理。免费电话或特价服务（1-800或1-900服务）是引入的补充服务的好例子。除了这些呼叫的重要特点是费用不同，因此呼叫方不必为免费电话付费，或为高费率呼叫支付额外费用之外，它们还有一个相似之处，即必须将所拨打的号码转换为目的地终端的“真实”地址。它们被称为数字翻译服务，构成了今天提供的所有补充服务的大部分。
These were originally programmed into each Central Office, but the complexity of maintaining the data tables on each processor grew cumbersome, so a more general solution was sought. After a considerable gestation period, the eventual solution was the Intelligent Network. This takes the separation of Central Offices and the network links interconnecting them a stage further.
这些程序最初被编入每个中央办公室，但在每个处理器上维护数据表的复杂性增加了麻烦，因此寻求了一种更通用的解决方案。经过相当长的酝酿期，最终的解决方案是智能网络。这使得中央办公室的分离和相互连接的网络链路更进一步。
The Central Offices are considered to provide the Call Control Function (CCF). In addition, the Service Switching Function (SSF) is provided to "enhance" the operation of these Switches by detecting when a particular request has been made (such as by dialing 1-800). If this pattern is detected, the equipment implementing the SSF will send a specialized request message over the signaling network to a separate computer that implements the Service Control Function (SCF). This entity is responsible for querying service specific data (held in a unit providing the Service Data Function, or SDF), performing any digit translations necessary, and sending the details of how to proceed back to the SSF, where they are obeyed and the call is put through to the "real" destination. In many implementations, the SDF is closely coupled to the SCF. This configuration is shown in Figure 18.
中央办公室被视为提供呼叫控制功能（CCF）。此外，还提供了服务切换功能（SSF），以通过检测何时发出特定请求（例如通过拨打1-800）来“增强”这些交换机的操作。如果检测到该模式，则实现SSF的设备将通过信令网络向实现服务控制功能（SCF）的单独计算机发送专用请求消息。该实体负责查询特定于服务的数据（保存在提供服务数据功能或SDF的单元中），执行任何必要的数字翻译，并将如何返回SSF的详细信息发送回SSF，在SSF中遵守这些信息并将呼叫转接到“真实”目的地。在许多实现中，SDF与SCF紧密耦合。此配置如图18所示。
[---] [---] [---]
/--\ [SRF] [SCF] [SDF]
()/\()__ [|-!] [-!-] [-!-]
/__\ \ || \.............!......!........
\ || / ! ! /--\
__ \ [|-!] [-!-] ! ()/\()
\ \ \__[SSF] [CCF] ! ___/__\
[Fax]________[CCF]=========[---]==\\ [!--] / __
\\========[CCF]__/ \ \
[---]_______[Fax]
Key: ___ access relationship
=== trunk relationship
... signaling relationship
[---] [---] [---]
/--\ [SRF] [SCF] [SDF]
()/\()__ [|-!] [-!-] [-!-]
/__\ \ || \.............!......!........
\ || / ! ! /--\
__ \ [|-!] [-!-] ! ()/\()
\ \ \__[SSF] [CCF] ! ___/__\
[Fax]________[CCF]=========[---]==\\ [!--] / __
\\========[CCF]__/ \ \
[---]_______[Fax]
Key: ___ access relationship
=== trunk relationship
... signaling relationship
Figure 18
图18
The advantage is that there can be a much smaller number of physical units dedicated to the SCF, and as they are connected to the signaling network they can be contacted by, and can send instructions back to, all of the units providing the SSF and thus the CCF.
优点是，专用于SCF的物理单元的数量可以少得多，并且当它们连接到信令网络时，它们可以被提供SSF的所有单元联系，并且可以将指令发送回CCF。
In another enhancement, a separate entity called the Special Resource Function (SRF) was defined. Equipment implementing this function includes announcement units to play recorded messages (for example, prompts to enter digits) to callers. It will also include the tone decoders needed to capture any digits pressed by the caller in response to the prompts. It is connected to the rest of the PSTN usually via trunk data links. It will also include a signaling connection (directly or indirectly) back to the SCF, via the PSTN's core signaling network.
在另一个增强中，定义了一个称为特殊资源功能（SRF）的单独实体。实现此功能的设备包括向呼叫者播放录制的消息（例如，提示输入数字）的公告单元。它还将包括所需的音调解码器，以捕获呼叫者根据提示按下的任何数字。它通常通过中继数据链路连接到PSTN的其余部分。它还将包括通过PSTN的核心信令网络（直接或间接）返回SCF的信令连接。
As an example of the way that these different functional entities interact, the SCF can ask an SSF handling a call to route the caller temporarily through to an SRF. In response to instructions sent to it from the SCF over the signaling network, the SRF can play announcements and can collect digits that the user presses on their terminal in response to prompts they are played. Once these digits have been collected they can be passed on to the SCF via a signaling message for further processing. In normal operation, the SCF would then ask the SSF to dissolve the temporary connection between the user's terminal and the SRF. This allows the collection of account numbers or passwords (or PINs) and forms the heart of many "Calling Card" services.
作为这些不同功能实体交互方式的示例，SCF可以请求处理呼叫的SSF将呼叫者临时路由到SRF。为了响应SCF通过信令网络向其发送的指令，SRF可以播放公告，并可以收集用户在其终端上按以响应播放提示的数字。一旦收集到这些数字，就可以通过信令消息将其传递给SCF进行进一步处理。在正常操作中，SCF然后会要求SSF解除用户终端和SRF之间的临时连接。这允许收集帐号或密码（或PIN），并构成许多“电话卡”服务的核心。
This pattern of user interaction is also used in a wide variety of other services where extra account information and PINs are needed. They are collected as just described and can be checked against the correct values stored in the service database prior to allowing the call to proceed.
这种用户交互模式也被广泛用于其他需要额外帐户信息和PIN的服务中。如前所述收集它们，并可在允许调用继续之前，对照服务数据库中存储的正确值进行检查。
The Intelligent Network functional entities can be realized as physical units in a number of different combinations. A common configuration is shown in Figure 19.
智能网络功能实体可以通过多种不同的组合实现为物理单元。常见配置如图19所示。
[---] [---] [---] [---]
/--\ [I.P] [SCP] [SDP] [SN ]
()/\()__ [|-!] [-!-] [-!-] [--|]
/__\ \ || \.............!.....!..... |
\ || / ! \ | /--\
__ \ [|-!] [-!-] \ | ()/\()
\ \ \__[SSP]=========[CO ]==\\ \ | ___/__\
[Fax]________[---] [---] \\ [!-|] / __
\\=======[CO ]__/ \ \
[---]_______[Fax]
[---] [---] [---] [---]
/--\ [I.P] [SCP] [SDP] [SN ]
()/\()__ [|-!] [-!-] [-!-] [--|]
/__\ \ || \.............!.....!..... |
\ || / ! \ | /--\
__ \ [|-!] [-!-] \ | ()/\()
\ \ \__[SSP]=========[CO ]==\\ \ | ___/__\
[Fax]________[---] [---] \\ [!-|] / __
\\=======[CO ]__/ \ \
[---]_______[Fax]
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
SSP Service Switching Point - a unit that implements the
Service Switching Function
CCP Call Control Point - a unit that performs call control
functions.
This is normally a kind of Central Office (shown as CO
above)
SCP Service Control Point - a unit implementing the Service
Control Function. NOTE that this is connected to the SS7
Network and uses this connection for all of its
communications.
I.P Intelligent Peripheral - a unit that contains specialized
resources (like announcement units, tone decoders).
In effect, it implements Special Resource Functions.
SN Service Node
Key: ___ Access Lines
=== Trunk Links (inter-CO user data links)
... Inter-CO signaling network links
SSP Service Switching Point - a unit that implements the
Service Switching Function
CCP Call Control Point - a unit that performs call control
functions.
This is normally a kind of Central Office (shown as CO
above)
SCP Service Control Point - a unit implementing the Service
Control Function. NOTE that this is connected to the SS7
Network and uses this connection for all of its
communications.
I.P Intelligent Peripheral - a unit that contains specialized
resources (like announcement units, tone decoders).
In effect, it implements Special Resource Functions.
SN Service Node
Figure 19
图19
This diagram also shows a unit called a Service Node, or SN. This contains components that realize all of the operational Intelligent Network functions (SSF, SCF, SDF, and SRF). It is sometimes more convenient to have all of these elements in one node (for example, for operations and maintenance reasons), particularly within smaller PSTNs or where there is a relatively low level of requests for
此图还显示了一个称为服务节点或SN的单元。其中包含实现所有操作智能网络功能（SSF、SCF、SDF和SRF）的组件。有时，将所有这些元素都放在一个节点中（例如，出于操作和维护原因）更方便，尤其是在较小的PSTN内，或者在请求的级别相对较低的情况下
particular services. Another difference is that, as they are all co-located, proprietary protocols can be used for internal communication, rather than the full Intelligent Network Application Part (INAP) protocol used over the core signaling network between discrete units. It also differs from the "unbundled" approach in that it is connected to the COs within a PSTN as a peripheral, having only an access connection to a Central Office; there is no connection to the core signaling network. Other than this, it operates in a similar way, and can provide the same kinds of services. Information on the specification of the Intelligent Network can be found in the ITU recommendations [1], while two books ([2] and [3]) describe the system, its history, operation, and the philosophy behind it.
特别服务。另一个不同之处是，由于它们都位于同一位置，因此可以使用专有协议进行内部通信，而不是在离散单元之间的核心信令网络上使用完整的智能网络应用部分（INAP）协议。它也不同于“非绑定”方法，因为它作为外围设备连接到PSTN内的COs，仅具有到中央办公室的接入连接；没有与核心信令网络的连接。除此之外，它以类似的方式运行，并且可以提供相同类型的服务。有关智能网络规范的信息可在ITU建议[1]中找到，而两本书（[2]和[3]）描述了该系统及其历史、操作和背后的原理。
A Call Center is a system that allows a company to be organized with a group of similar individuals (agents), all of whom can either make calls to, or take calls from, customers. The system distributes incoming calls to the agents based on their availability and automates the placement of outgoing calls, selecting an agent to handle the call and routing the call to them only once the call request has been made of the PSTN.
呼叫中心是一个系统，允许公司由一群类似的个人（代理人）组成，所有人都可以打电话给客户或接听客户的电话。系统根据代理的可用性将传入呼叫分配给代理，并自动安排传出呼叫，选择代理处理呼叫，并仅在PSTN发出呼叫请求后将呼叫路由给代理。
The incoming call distribution feature ("automatic call distribution", or ACD) is usually coupled with a call queuing scheme. In this scheme, the callers are connected temporarily with an announcement unit that normally plays music. The calls are treated in sequence so that (once the caller is at the front of the queue) the ACD system selects the next available agent and routes the call through to them.
来电分配功能（“自动呼叫分配”或ACD）通常与呼叫排队方案相结合。在该方案中，呼叫者临时与通常播放音乐的广播单元连接。按顺序处理调用，以便（一旦调用方位于队列前面）ACD系统选择下一个可用的代理并将调用路由到它们。
Another feature connects a customer making an incoming call to a unit that asks them for some information on the purpose of their call, selecting the agent to handle the call based on the particular area of expertise needed; to do this, the agents are further categorized by their knowledge (or "Skill Set"). If this skill set categorization is used then by implication there will be separate queues for each of the skill sets. This user selection scheme can be used independently of the others. For example these so-called "voice navigation systems" can be used to select a particular department extension number, based on the function required by the customer; as such, they can automate the job of company telephone receptionist in routing incoming calls.
另一项功能将拨打来电的客户连接到一个单元，该单元要求客户提供有关其通话目的的一些信息，并根据所需的特定专业领域选择代理来处理通话；为此，代理将根据其知识（或“技能集”）进一步分类。如果使用此技能集分类，则暗示每个技能集将有单独的队列。此用户选择方案可以独立于其他方案使用。例如，这些所谓的“语音导航系统”可用于根据客户要求的功能选择特定的部门分机号码；因此，他们可以自动完成公司电话接线员在路由来电方面的工作。
Where possible, the information gleaned from the customer can be provided to the selected agent, usually via a separate networked computer connection. Similarly, if an outgoing call is being made to one of a list of customers, information on the customer and the purpose of the call can be provided to the agent selected to handle
在可能的情况下，通常通过单独的联网计算机连接，可以将从客户处收集的信息提供给选定的代理。类似地，如果正在向客户列表中的一个拨打呼出电话，则可以向选择处理的代理提供有关客户和通话目的的信息
the call. Such configurations are generally called "Computer Telephony Integration" or CTI systems. Strictly, a CTI system can be arranged to handle routing of incoming calls and automation of outgoing calls only (also known as computer integrated telephony features), without the agents having access to a network of computers. However, the business case for combining the telephony functions of the call center with provision to the agents of computers with customer information can be compelling.
电话。这种配置通常称为“计算机电话集成”或CTI系统。严格来说，CTI系统只能处理传入呼叫的路由和传出呼叫的自动化（也称为计算机集成电话功能），而不需要代理访问计算机网络。然而，将呼叫中心的电话功能与向计算机代理提供客户信息相结合的商业案例可能是令人信服的。
This is often further combined with a company's order and service processing computer system. In this case, a call is treated as part of a business transaction, with the information to be exchanged captured as fields of a computer form. While such a computer system is not, strictly, part of a call center, integrating the company computer system with the call center is very common. This allows the details of the call to be stored on a centralized database, allowing further automated order processing, for example. It also allows the call to be transferred from one agent to another where needed, ensuring that the new agent has the information already captured. This might be useful if someone with a different area of expertise were to be needed to handle the customer's requirements.
这通常与公司的订单和服务处理计算机系统进一步结合。在这种情况下，调用被视为业务事务的一部分，要交换的信息被捕获为计算机表单的字段。虽然严格来说，这种计算机系统不是呼叫中心的一部分，但将公司计算机系统与呼叫中心集成是非常常见的。这允许调用的详细信息存储在一个集中的数据库中，例如，允许进一步的自动化订单处理。它还允许在需要时将呼叫从一个代理转移到另一个代理，确保新代理已捕获信息。如果需要具有不同专业领域的人员来处理客户的需求，这可能很有用。
Traditionally, Call Centers have been used to support teams of agents working at a single site (or a small number of sites, with private telephony trunks interconnecting them). The site Private Automatic Branch eXchange (PABX) was integrated with a computer system to provide these features to people at that site. There can be a business case for provision of such features to distributed teams of workers as well. In particular, the possibility of providing support for people working from home has been seen as important. Some of the Call Center features have been incorporated into public telephone exchanges or Central Offices (COs) from many manufacturers as part of their "Centrex" service offerings.
传统上，呼叫中心用于支持在单个站点（或少量站点，通过专用电话中继线将其互连）工作的代理团队。站点专用自动交换机（PABX）与计算机系统集成，为该站点的用户提供这些功能。也可以有一个向分布式工作团队提供此类功能的商业案例。特别是，为在家工作的人提供支持的可能性被视为非常重要。许多制造商已将呼叫中心的一些功能纳入公共电话交换机或中央办公室（COs），作为其“Centrex”服务产品的一部分。
There are practical limitations in providing such features on COs. Apart from the procedures needed to configure these features for any telephone line that is to use them, the basic requirement that every agent must have a connection to the supporting CO can limit its usefulness. Another approach is to provide Call Center features via the Intelligent Network. The features might thus be provided over a Telephone Operator's entire network, and would mean that the Call Center could be configured centrally while still allowing agents to be located anywhere within the telephone network. It also means that the supported company can pay for the Call Center features "as they go" rather than having a high "up front" cost.
在COs上提供此类功能存在实际限制。除了为使用这些功能的任何电话线配置这些功能所需的程序外，每个代理必须与支持CO建立连接这一基本要求可能会限制其用途。另一种方法是通过智能网络提供呼叫中心功能。因此，这些功能可以通过电话运营商的整个网络提供，这意味着呼叫中心可以集中配置，同时仍然允许代理位于电话网络中的任何位置。这还意味着，受支持的公司可以“随用随付”，而不是支付高昂的“前期”成本。
[1] ITU-T Q.12xx Recommendation Series, Geneva, 1995.
[1] ITU-T Q.12xx建议系列，日内瓦，1995年。
[2] I. Faynberg, L. R. Gabuzda, M. P. Kaplan, and N. J. Shah, "The Intelligent Network Standards, their Application to Services", McGraw-Hill, 1996.
[2] I.Faynberg、L.R.Gabuzda、M.P.Kaplan和N.J.Shah，“智能网络标准及其在服务中的应用”，McGraw-Hill，1996年。
[3] T. Magedanz and R. Popesku-Zeletin, "Intelligent Networks: Basic Technology, Standards and Evolution", Intl. Thomson Computer Press, 1996.
[3] T.Magedanz和R.Popesku Zeletin，“智能网络：基本技术、标准和演变”，国际汤姆森计算机出版社，1996年。
[4] Information processing systems - Open Systems Interconnection - Specification of Abstract Syntax Notation One (ASN.1), International Organization for Standardization, International Standard 8824, December, 1987.
[4] 信息处理系统.开放系统互连.抽象语法符号1规范（ASN.1），国际标准化组织，国际标准88241987年12月。
[5] McCloghrie, K., Editor, "Structure of Management Information for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1902, January 1996.
[5] McCloghrie，K.，编辑，“简单网络管理协议（SNMPv2）第2版的管理信息结构”，RFC 1902，1996年1月。
[6] Kristol, D. and L. Montulli, "HTTP State Management Mechanism", RFC 2109, February 1997.
[6] Kristol，D.和L.Montulli，“HTTP状态管理机制”，RFC 2109，1997年2月。
[7] Zimmerman, D., "The Finger User Information Protocol", RFC 1288 December 1991.
[7] Zimmerman，D.，“手指用户信息协议”，RFC 1288，1991年12月。
Authors' Addresses
作者地址
Steve Bellovin AT&T Labs Room E-215 180 Park Ave. Bldg. 103 Florham Park, NJ 07932-0000 USA
Steve Bellovin AT&T实验室E-215室美国新泽西州弗洛勒姆公园103号公园大道180号大厦07932-0000
Phone: +1 973 360 8656
Fax: +1 973 360 8077
EMail: smb@research.att.com
Phone: +1 973 360 8656
Fax: +1 973 360 8077
EMail: smb@research.att.com
Fred M. Burg AT&T Labs Room 1N-117 307 Middletown Lincroft Road Lincroft, NJ 07738 USA
Fred M.Burg AT&T实验室美国新泽西州林克罗夫特市林克罗夫特路307号1N-117室，邮编：07738
Phone: +1 732 576 4322
Fax: +1 732 576 4317
EMail: fburg@hogpb.att.com
Phone: +1 732 576 4322
Fax: +1 732 576 4317
EMail: fburg@hogpb.att.com
Lawrence Conroy Roke Manor Research Limited IT&N-INIA Group Roke Manor, Old Salisbury Lane, Romsey, Hampshire SO51 0ZN U.K.
劳伦斯康罗伊洛克庄园研究有限公司和N-INA集团洛克庄园，旧索尔兹伯里巷，Romsey，汉普郡SO51 0Zn UK。
Phone: +44 1794 833666
Fax: +44 1794 833434
EMail: lwc@roke.co.uk
Phone: +44 1794 833666
Fax: +44 1794 833434
EMail: lwc@roke.co.uk
Paul Davidson Nortel P.O.Box 3511 Station "C" Mail Stop 242 Ottawa, Ontario, Canada K1Y 4H7
Paul Davidson Nortel邮政信箱3511“C”站邮递站242加拿大安大略省渥太华K1Y 4H7
Phone: +1 613 763 4234
EMail: pauldav@nortel.ca
Phone: +1 613 763 4234
EMail: pauldav@nortel.ca
A. DeSimone Lucent Technologies Room 6H510 600-700 Mountain Avenue Murray Hill, NJ 07974-0636 USA
A.DeSimone-Lucent Technologies室6H510 600-700美国新泽西州默里山山路07974-0636
Phone: +1 908 582 2382
Fax: +1 908 582 1086
E-Mail:tds@lucent.com
Phone: +1 908 582 2382
Fax: +1 908 582 1086
E-Mail:tds@lucent.com
Murali Krishnaswamy Bell Laboratories Lucent Technologies Room 2G-527a 101 Crawfords Corner Road Holmdel, NJ 07733-3030 USA
Murali Krishnaswamy Bell Laboratories Lucent Technologies 2G-527a室美国新泽西州霍尔德尔克劳福德角路101号，邮编07733-3030
Phone: +1 732 949 3611
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EMail: murali@bell-labs.com
Phone: +1 732 949 3611
Fax: +1 732 949 3210
EMail: murali@bell-labs.com
Hui-Lan Lu Bell Laboratories Lucent Technologies Room 4K-309 101 Crawfords Corner Road Holmdel, NJ 07733-3030 USA
美国新泽西州霍姆德尔克劳福德角路101号惠兰路贝尔实验室朗讯科技4K-309室07733-3030
Phone: +1 732 949 0321
Fax: +1 732 949 1196
EMail: hui-lan.lu@bell-labs.com
Phone: +1 732 949 0321
Fax: +1 732 949 1196
EMail: hui-lan.lu@bell-labs.com
Henning Schulzrinne Dept. of Computer Science Columbia University New York, NY 10027 USA
美国纽约哥伦比亚大学计算机科学系
Phone: +1 212 939 7042 (@Bell Labs: 732 949 8344)
Fax: +1 212 666 0140
EMail: schulzrinne@cs.columbia.edu
Phone: +1 212 939 7042 (@Bell Labs: 732 949 8344)
Fax: +1 212 666 0140
EMail: schulzrinne@cs.columbia.edu
Kamlesh T. Tewani AT&T Labs Room 1K-334 101, Crawfords Corner Rd. Holmdel, NJ 07733 USA
美国新泽西州霍姆德尔克劳福德角路101号Kamlesh T.Tewani AT&T实验室1K-334室，邮编：07733
Phone: +1 732 949 5369
Fax: +1 732 949 8569
EMail: tewani@att.com
Phone: +1 732 949 5369
Fax: +1 732 949 8569
EMail: tewani@att.com
Kumar Vishwanathan Isochrone EMail: kumar@isochrone.com
Kumar Vishwanathan等时线电子邮件：kumar@isochrone.com
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Copyright (C) The Internet Society (1998). All Rights Reserved.
版权所有（C）互联网协会（1998年）。版权所有。
This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English.
本文件及其译本可复制并提供给他人，对其进行评论或解释或协助其实施的衍生作品可全部或部分编制、复制、出版和分发，不受任何限制，前提是上述版权声明和本段包含在所有此类副本和衍生作品中。但是，不得以任何方式修改本文件本身，例如删除版权通知或对互联网协会或其他互联网组织的引用，除非出于制定互联网标准的需要，在这种情况下，必须遵循互联网标准过程中定义的版权程序，或根据需要将其翻译成英语以外的其他语言。
The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns.
上述授予的有限许可是永久性的，互联网协会或其继承人或受让人不会撤销。
This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
本文件和其中包含的信息是按“原样”提供的，互联网协会和互联网工程任务组否认所有明示或暗示的保证，包括但不限于任何保证，即使用本文中的信息不会侵犯任何权利，或对适销性或特定用途适用性的任何默示保证。