Internet Engineering Task Force (IETF) S. Nandakumar
Request for Comments: 7850 Cisco Systems Inc
Category: Standards Track April 2016
ISSN: 2070-1721
Internet Engineering Task Force (IETF) S. Nandakumar
Request for Comments: 7850 Cisco Systems Inc
Category: Standards Track April 2016
ISSN: 2070-1721
Registering Values of the SDP 'proto' Field for Transporting RTP Media over TCP under Various RTP Profiles
注册SDP“proto”字段的值，以便在各种RTP配置文件下通过TCP传输RTP介质
Abstract
摘要
The Real-time Transport Protocol (RTP) specification establishes a registry of profile names for use by higher-level control protocols, such as the Session Description Protocol (SDP), to refer to the transport methods. This specification describes the following new SDP transport protocol identifiers for transporting RTP Media over TCP: 'TCP/RTP/AVPF', 'TCP/RTP/SAVP', 'TCP/RTP/SAVPF', 'TCP/DTLS/RTP/SAVP', 'TCP/DTLS/RTP/SAVPF', 'TCP/TLS/RTP/AVP', and 'TCP/TLS/RTP/AVPF'.
实时传输协议（RTP）规范建立了一个配置文件名称注册表，供更高级别的控制协议（如会话描述协议（SDP））使用，以引用传输方法。本规范描述了以下通过TCP传输RTP介质的新SDP传输协议标识符：“TCP/RTP/AVPF”、“TCP/RTP/SAVP”、“TCP/RTP/SAVP”、“TCP/DTLS/RTP/SAVP”、“TCP/DTLS/RTP/SAVPF”、“TCP/TLS/RTP/AVP”和“TCP/TLS/RTP/AVPF”。
Status of This Memo
关于下段备忘
This is an Internet Standards Track document.
这是一份互联网标准跟踪文件。
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。它代表了IETF社区的共识。它已经接受了公众审查，并已被互联网工程指导小组（IESG）批准出版。有关互联网标准的更多信息，请参见RFC 5741第2节。
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7850.
有关本文件当前状态、任何勘误表以及如何提供反馈的信息，请访问http://www.rfc-editor.org/info/rfc7850.
Copyright Notice
版权公告
Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2016 IETF信托基金和确定为文件作者的人员。版权所有。
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Protocol Identifiers . . . . . . . . . . . . . . . . . . . . 3
3.1. TCP/RTP/AVPF Transport Realization . . . . . . . . . . . 3
3.2. TCP/RTP/SAVP Transport Realization . . . . . . . . . . . 3
3.3. TCP/RTP/SAVPF Transport Realization . . . . . . . . . . . 3
3.4. TCP/DTLS/RTP/SAVP Transport Realization . . . . . . . . . 3
3.5. TCP/DTLS/RTP/SAVPF Transport Realization . . . . . . . . 4
3.6. TCP/TLS/RTP/AVP Transport Realization . . . . . . . . . . 4
3.7. TCP/TLS/RTP/AVPF Transport Realization . . . . . . . . . 4
4. ICE Considerations . . . . . . . . . . . . . . . . . . . . . 4
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4
6. Security Considerations . . . . . . . . . . . . . . . . . . . 5
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 5
7.1. Normative References . . . . . . . . . . . . . . . . . . 5
7.2. Informative References . . . . . . . . . . . . . . . . . 6
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 7
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 7
1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Protocol Identifiers . . . . . . . . . . . . . . . . . . . . 3
3.1. TCP/RTP/AVPF Transport Realization . . . . . . . . . . . 3
3.2. TCP/RTP/SAVP Transport Realization . . . . . . . . . . . 3
3.3. TCP/RTP/SAVPF Transport Realization . . . . . . . . . . . 3
3.4. TCP/DTLS/RTP/SAVP Transport Realization . . . . . . . . . 3
3.5. TCP/DTLS/RTP/SAVPF Transport Realization . . . . . . . . 4
3.6. TCP/TLS/RTP/AVP Transport Realization . . . . . . . . . . 4
3.7. TCP/TLS/RTP/AVPF Transport Realization . . . . . . . . . 4
4. ICE Considerations . . . . . . . . . . . . . . . . . . . . . 4
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4
6. Security Considerations . . . . . . . . . . . . . . . . . . . 5
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 5
7.1. Normative References . . . . . . . . . . . . . . . . . . 5
7.2. Informative References . . . . . . . . . . . . . . . . . 6
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 7
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 7
The Real-time Transport Protocol (RTP) provides end-to-end network transport functions suitable for applications transmitting real-time data such as audio or video over multicast or unicast network services. The data transport is augmented by the RTP Control Protocol (RTCP) to allow monitoring of the data delivery in a manner scalable to large multicast networks and to provide minimal control and identification functionality.
实时传输协议（RTP）提供端到端网络传输功能，适用于通过多播或单播网络服务传输实时数据（如音频或视频）的应用。RTP控制协议（RTCP）增强了数据传输，允许以可扩展到大型多播网络的方式监控数据传输，并提供最小的控制和识别功能。
"SDP: Session Description Protocol" [RFC4566] provides a general-purpose format for describing multimedia sessions in announcements or invitations. "TCP-Based Media Transport in the Session Description Protocol (SDP)" [RFC4145] specifies a general mechanism for describing media transport over TCP using SDP with [RFC4571] defining a method for framing RTP and RTCP packets [RFC3550] onto a connection-oriented transport (such as TCP). "Connection-Oriented Media Transport over the Transport Layer Security (TLS) Protocol in the Session Description Protocol (SDP)" [RFC4572] extends [RFC4145] for describing TCP-based media streams that are protected using TLS [RFC5246].
“SDP:会话描述协议”[RFC4566]提供了一种通用格式，用于描述公告或邀请中的多媒体会话。“会话描述协议（SDP）中基于TCP的媒体传输”[RFC4145]指定了使用SDP描述TCP上媒体传输的一般机制，其中[RFC4571]定义了将RTP和RTCP数据包[RFC3550]分帧到面向连接的传输（如TCP）上的方法。“会话描述协议（SDP）中传输层安全（TLS）协议上的面向连接的媒体传输”[RFC4572]扩展了[RFC4145]，用于描述使用TLS保护的基于TCP的媒体流[RFC5246]。
This specification describes additional SDP transport protocol identifiers for transporting RTP media over TCP as defined in Section 3.
本规范描述了第3节中定义的用于通过TCP传输RTP介质的附加SDP传输协议标识符。
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119].
本文件中的关键词“必须”、“不得”、“要求”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照RFC 2119[RFC2119]中所述进行解释。
The "m=" line in SDP specifies, among other items, the transport protocol (identified via the "proto" field) to be used for the media in the session. See Section 5.14 (Media Descriptions) of SDP [RFC4566] for a discussion on transport protocol identifiers.
SDP中的“m=”行指定了会话中媒体使用的传输协议（通过“proto”字段标识）。有关传输协议标识符的讨论，请参见SDP[RFC4566]第5.14节（媒体描述）。
The following is the format for an "m=" line, as specified in [RFC4566]:
以下是[RFC4566]中指定的“m=”行的格式：
m=<media> <port> <proto> <fmt> ...
m=<media><port><proto><fmt>。。。
The TCP/RTP/AVPF transport describes RTP media with RTCP-based feedback [RFC4585] over TCP.
TCP/RTP/AVPF传输描述了RTP媒体通过TCP提供基于RTCP的反馈[RFC4585]。
The RTP/AVPF stream over TCP is realized using the framing method defined in [RFC4571].
TCP上的RTP/AVPF流是使用[RFC4571]中定义的帧方法实现的。
The TCP/RTP/SAVP transport describes Secure RTP (SRTP) media [RFC3711] over TCP.
TCP/RTP/SAVP传输描述了TCP上的安全RTP（SRTP）媒体[RFC3711]。
The RTP/SAVP stream over TCP is realized using the framing method defined in [RFC4571].
TCP上的RTP/SAVP流是使用[RFC4571]中定义的帧方法实现的。
The TCP/RTP/SAVPF transport describes Secure RTP media with RTCP-based feedback [RFC5124] over TCP.
TCP/RTP/SAVPF传输描述了安全的RTP媒体，该媒体通过TCP提供基于RTCP的反馈[RFC5124]。
The RTP/SAVPF stream over TCP is realized using the framing method defined in [RFC4571].
TCP上的RTP/SAVPF流是使用[RFC4571]中定义的帧方法实现的。
The TCP/DTLS/RTP/SAVP transport describes Secure RTP media [RFC3711] using Datagram Transport Layer Security SRTP (DTLS-SRTP) [RFC5764] over TCP.
TCP/DTLS/RTP/SAVP传输描述了通过TCP使用数据报传输层安全SRTP（DTLS-SRTP）[RFC5764]的安全RTP媒体[RFC3711]。
RTP/SAVP using DTLS-based key establishment is realized according to the procedures defined in [RFC5764]. Also, the framing specified in [RFC4571] is used to transport DTLS-SRTP packets over TCP.
根据[RFC5764]中定义的程序，使用基于DTLS的密钥建立实现RTP/SAVP。此外，[RFC4571]中指定的帧用于通过TCP传输DTLS-SRTP数据包。
The TCP/DTLS/RTP/SAVPF transport describes Secure RTP media with RTCP-based feedback [RFC5124] using DTLS-SRTP over TCP.
TCP/DTLS/RTP/SAVPF传输描述了在TCP上使用DTLS-SRTP的基于RTCP的反馈[RFC5124]的安全RTP媒体。
RTP/SAVPF using DTLS-based key establishment is realized according to the procedures defined in [RFC5764]. Also, the framing specified in [RFC4571] is used to transport DTLS-SRTP packets over TCP.
根据[RFC5764]中定义的程序，使用基于DTLS的密钥建立实现RTP/SAVPF。此外，[RFC4571]中指定的帧用于通过TCP传输DTLS-SRTP数据包。
The TCP/TLS/RTP/AVP transport describes RTP Media on top of TLS over TCP.
TCP/TLS/RTP/AVP传输描述了TCP上TLS之上的RTP介质。
RTP/AVP packets are framed using the procedures from [RFC4571] and are transported as application data messages over the TLS association setup using the procedures from [RFC4572].
RTP/AVP数据包使用[RFC4571]中的程序进行帧化，并使用[RFC4572]中的程序通过TLS关联设置作为应用程序数据消息进行传输。
The TCP/TLS/RTP/AVPF transport describes RTP media with RTCP-based feedback [RFC5124] on top of TLS over TCP.
TCP/TLS/RTP/AVPF传输描述了在TCP上的TLS之上具有基于RTCP的反馈[RFC5124]的RTP媒体。
RTP/AVPF packets are framed using the procedures from [RFC4571] and are transported as application data messages over the TLS association setup using the procedures from [RFC4572].
RTP/AVPF数据包使用[RFC4571]中的程序进行帧化，并使用[RFC4572]中的程序作为应用程序数据消息通过TLS关联设置进行传输。
When procedures from [RFC6544] are used to set up Interactive Connectivity Establishment (ICE) [RFC5245] candidates for a TCP transport, the framing mechanism from [RFC4571] MUST be used for framing Session Traversal Utilities for NAT (STUN) packets (for keepalives and consent checks), as defined in Section 3 of [RFC6544].
当[RFC6544]中的程序用于为TCP传输设置交互式连接建立（ICE）[RFC5245]候选时，[RFC4571]中的成帧机制必须用于NAT（STUN）数据包的成帧会话遍历实用程序（用于保留和同意检查），如[RFC6544]第3节所定义。
This specification describes the following new SDP transport protocol identifiers: 'TCP/RTP/AVPF', 'TCP/RTP/SAVP', 'TCP/RTP/SAVPF', 'TCP/DTLS/RTP/SAVP', 'TCP/DTLS/RTP/SAVPF', 'TCP/TLS/RTP/AVP', and 'TCP/TLS/RTP/AVPF', as defined in Section 3. These values have been registered by the IANA under the "proto" subregistry in the "Session Description Protocol (SDP) Parameters" registry.
本规范描述了以下新的SDP传输协议标识符：“TCP/RTP/AVPF”、“TCP/RTP/SAVP”、“TCP/RTP/SAVP”、“TCP/DTLS/RTP/SAVP”、“TCP/DTLS/RTP/SAVPF”、“TCP/TLS/RTP/AVP”和“TCP/TLS/RTP/AVPF”，如第3节所定义。IANA已在“会话描述协议（SDP）参数”注册表中的“proto”子区下注册了这些值。
+--------+---------------------+-----------+
| Type | SDP Name | Reference |
+--------+---------------------+-----------+
| proto | TCP/RTP/AVPF | RFC 7850 |
| | | |
| proto | TCP/RTP/SAVP | RFC 7850 |
| | | |
| proto | TCP/RTP/SAVPF | RFC 7850 |
| | | |
| proto | TCP/DTLS/RTP/SAVP | RFC 7850 |
| | | |
| proto | TCP/DTLS/RTP/SAVPF | RFC 7850 |
| | | |
| proto | TCP/TLS/RTP/AVP | RFC 7850 |
| | | |
| proto | TCP/TLS/RTP/AVPF | RFC 7850 |
+--------+---------------------+-----------+
+--------+---------------------+-----------+
| Type | SDP Name | Reference |
+--------+---------------------+-----------+
| proto | TCP/RTP/AVPF | RFC 7850 |
| | | |
| proto | TCP/RTP/SAVP | RFC 7850 |
| | | |
| proto | TCP/RTP/SAVPF | RFC 7850 |
| | | |
| proto | TCP/DTLS/RTP/SAVP | RFC 7850 |
| | | |
| proto | TCP/DTLS/RTP/SAVPF | RFC 7850 |
| | | |
| proto | TCP/TLS/RTP/AVP | RFC 7850 |
| | | |
| proto | TCP/TLS/RTP/AVPF | RFC 7850 |
+--------+---------------------+-----------+
The new "proto" identifiers registered by this document in the SDP parameters registry maintained by IANA are primarily for use by the offer/answer model of the Session Description Protocol [RFC3264] for the negotiation and establishment of RTP-based media over the TCP transport. This specification doesn't introduce any additional security considerations beyond those specified by the individual transport protocols identified in the "proto" identifiers and those detailed in Section 7 of [RFC4566].
本文件在IANA维护的SDP参数注册表中注册的新“原始”标识符主要用于会话描述协议[RFC3264]的提供/应答模型，用于通过TCP传输协商和建立基于RTP的媒体。除了“协议”标识符中确定的单个传输协议和[RFC4566]第7节中详述的传输协议外，本规范未引入任何其他安全注意事项。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <http://www.rfc-editor.org/info/rfc2119>.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，DOI 10.17487/RFC2119，1997年3月<http://www.rfc-editor.org/info/rfc2119>.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session Description Protocol", RFC 4566, DOI 10.17487/RFC4566, July 2006, <http://www.rfc-editor.org/info/rfc4566>.
[RFC4566]Handley，M.，Jacobson，V.，和C.Perkins，“SDP：会话描述协议”，RFC 4566，DOI 10.17487/RFC4566，2006年7月<http://www.rfc-editor.org/info/rfc4566>.
[RFC4571] Lazzaro, J., "Framing Real-time Transport Protocol (RTP) and RTP Control Protocol (RTCP) Packets over Connection-Oriented Transport", RFC 4571, DOI 10.17487/RFC4571, July 2006, <http://www.rfc-editor.org/info/rfc4571>.
[RFC4571]Lazzaro，J.，“面向连接传输上的帧实时传输协议（RTP）和RTP控制协议（RTCP）数据包”，RFC 4571，DOI 10.17487/RFC4571，2006年7月<http://www.rfc-editor.org/info/rfc4571>.
[RFC4572] Lennox, J., "Connection-Oriented Media Transport over the Transport Layer Security (TLS) Protocol in the Session Description Protocol (SDP)", RFC 4572, DOI 10.17487/RFC4572, July 2006, <http://www.rfc-editor.org/info/rfc4572>.
[RFC4572]Lennox，J.，“会话描述协议（SDP）中传输层安全（TLS）协议上的面向连接的媒体传输”，RFC 4572，DOI 10.17487/RFC4572，2006年7月<http://www.rfc-editor.org/info/rfc4572>.
[RFC5245] Rosenberg, J., "Interactive Connectivity Establishment (ICE): A Protocol for Network Address Translator (NAT) Traversal for Offer/Answer Protocols", RFC 5245, DOI 10.17487/RFC5245, April 2010, <http://www.rfc-editor.org/info/rfc5245>.
[RFC5245]Rosenberg，J.，“交互式连接建立（ICE）：提供/应答协议的网络地址转换器（NAT）遍历协议”，RFC 5245，DOI 10.17487/RFC5245，2010年4月<http://www.rfc-editor.org/info/rfc5245>.
[RFC5764] McGrew, D. and E. Rescorla, "Datagram Transport Layer Security (DTLS) Extension to Establish Keys for the Secure Real-time Transport Protocol (SRTP)", RFC 5764, DOI 10.17487/RFC5764, May 2010, <http://www.rfc-editor.org/info/rfc5764>.
[RFC5764]McGrew，D.和E.Rescorla，“为安全实时传输协议（SRTP）建立密钥的数据报传输层安全（DTLS）扩展”，RFC 5764，DOI 10.17487/RFC5764，2010年5月<http://www.rfc-editor.org/info/rfc5764>.
[RFC6544] Rosenberg, J., Keranen, A., Lowekamp, B., and A. Roach, "TCP Candidates with Interactive Connectivity Establishment (ICE)", RFC 6544, DOI 10.17487/RFC6544, March 2012, <http://www.rfc-editor.org/info/rfc6544>.
[RFC6544]Rosenberg，J.，Keranen，A.，Lowekamp，B.，和A.Roach，“具有交互式连接建立（ICE）的TCP候选者”，RFC 6544，DOI 10.17487/RFC65442012年3月<http://www.rfc-editor.org/info/rfc6544>.
[RFC3264] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model with Session Description Protocol (SDP)", RFC 3264, DOI 10.17487/RFC3264, June 2002, <http://www.rfc-editor.org/info/rfc3264>.
[RFC3264]Rosenberg，J.和H.Schulzrinne，“具有会话描述协议（SDP）的提供/应答模型”，RFC 3264，DOI 10.17487/RFC3264，2002年6月<http://www.rfc-editor.org/info/rfc3264>.
[RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V. Jacobson, "RTP: A Transport Protocol for Real-Time Applications", STD 64, RFC 3550, DOI 10.17487/RFC3550, July 2003, <http://www.rfc-editor.org/info/rfc3550>.
[RFC3550]Schulzrinne，H.，Casner，S.，Frederick，R.，和V.Jacobson，“RTP：实时应用的传输协议”，STD 64，RFC 3550，DOI 10.17487/RFC3550，2003年7月<http://www.rfc-editor.org/info/rfc3550>.
[RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K. Norrman, "The Secure Real-time Transport Protocol (SRTP)", RFC 3711, DOI 10.17487/RFC3711, March 2004, <http://www.rfc-editor.org/info/rfc3711>.
[RFC3711]Baugher，M.，McGrew，D.，Naslund，M.，Carrara，E.，和K.Norrman，“安全实时传输协议（SRTP）”，RFC 3711，DOI 10.17487/RFC3711，2004年3月<http://www.rfc-editor.org/info/rfc3711>.
[RFC4145] Yon, D. and G. Camarillo, "TCP-Based Media Transport in the Session Description Protocol (SDP)", RFC 4145, DOI 10.17487/RFC4145, September 2005, <http://www.rfc-editor.org/info/rfc4145>.
[RFC4145]Yon，D.和G.Camarillo，“会话描述协议（SDP）中基于TCP的媒体传输”，RFC 4145，DOI 10.17487/RFC4145，2005年9月<http://www.rfc-editor.org/info/rfc4145>.
[RFC4585] Ott, J., Wenger, S., Sato, N., Burmeister, C., and J. Rey, "Extended RTP Profile for Real-time Transport Control Protocol (RTCP)-Based Feedback (RTP/AVPF)", RFC 4585, DOI 10.17487/RFC4585, July 2006, <http://www.rfc-editor.org/info/rfc4585>.
[RFC4585]Ott，J.，Wenger，S.，Sato，N.，Burmeister，C.，和J.Rey，“基于实时传输控制协议（RTCP）的反馈（RTP/AVPF）的扩展RTP配置文件”，RFC 4585，DOI 10.17487/RFC4585，2006年7月<http://www.rfc-editor.org/info/rfc4585>.
[RFC5124] Ott, J. and E. Carrara, "Extended Secure RTP Profile for Real-time Transport Control Protocol (RTCP)-Based Feedback (RTP/SAVPF)", RFC 5124, DOI 10.17487/RFC5124, February 2008, <http://www.rfc-editor.org/info/rfc5124>.
[RFC5124]Ott，J.和E.Carrara，“基于实时传输控制协议（RTCP）的反馈扩展安全RTP配置文件（RTP/SAVPF）”，RFC 5124DOI 10.17487/RFC5124，2008年2月<http://www.rfc-editor.org/info/rfc5124>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security (TLS) Protocol Version 1.2", RFC 5246, DOI 10.17487/RFC5246, August 2008, <http://www.rfc-editor.org/info/rfc5246>.
[RFC5246]Dierks，T.和E.Rescorla，“传输层安全（TLS）协议版本1.2”，RFC 5246，DOI 10.17487/RFC5246，2008年8月<http://www.rfc-editor.org/info/rfc5246>.
Acknowledgements
致谢
The author would like to thank Cullen Jennings, Alissa Cooper, Justin Uberti, Mo Zanaty, Christer Holmberg, Jonathan Lennox, Flemming Andreason, Roni Even, Ben Campbell, and Bo Burman for their reviews and suggested improvements.
作者要感谢Cullen Jennings、Alissa Cooper、Justin Uberti、Mo Zanaty、Christer Holmberg、Jonathan Lennox、Flemming Andreason、Roni Even、Ben Campbell和Bo Burman的评论和改进建议。
The author would also like to thank Adam Montville for the SecDir review, Meral Shirazipour for the Gen-ART review, and Sarah Banks for the OPS-Dir review.
作者还要感谢亚当·蒙特维尔（Adam Montville）的SecDir评论，梅拉尔·西拉齐波尔（Meral Shirazipour）的Gen ART评论，以及莎拉·班克斯（Sarah Banks）的OPS Dir评论。
Author's Address
作者地址
Suhas Nandakumar Cisco Systems Inc 707 Tasman Drive San Jose, CA 95134 United States
美国加利福尼亚州圣何塞塔斯曼大道707号Suhas Nandakumar思科系统公司，邮编95134
Email: snandaku@cisco.com
Email: snandaku@cisco.com