Internet Engineering Task Force (IETF) A. Begen
Request for Comments: 7022 Cisco
Obsoletes: 6222 C. Perkins
Updates: 3550 University of Glasgow
Category: Standards Track D. Wing
ISSN: 2070-1721 Cisco
E. Rescorla
RTFM, Inc.
September 2013
Internet Engineering Task Force (IETF) A. Begen
Request for Comments: 7022 Cisco
Obsoletes: 6222 C. Perkins
Updates: 3550 University of Glasgow
Category: Standards Track D. Wing
ISSN: 2070-1721 Cisco
E. Rescorla
RTFM, Inc.
September 2013
Guidelines for Choosing RTP Control Protocol (RTCP) Canonical Names (CNAMEs)
选择RTP控制协议（RTCP）规范名称（CNAMEs）的指南
Abstract
摘要
The RTP Control Protocol (RTCP) Canonical Name (CNAME) is a persistent transport-level identifier for an RTP endpoint. While the Synchronization Source (SSRC) identifier of an RTP endpoint may change if a collision is detected or when the RTP application is restarted, its RTCP CNAME is meant to stay unchanged, so that RTP endpoints can be uniquely identified and associated with their RTP media streams.
RTP控制协议（RTCP）规范名称（CNAME）是RTP端点的持久传输级别标识符。如果检测到冲突或RTP应用程序重新启动，RTP端点的同步源（SSRC）标识符可能会更改，但其RTCP CNAME将保持不变，以便RTP端点可以唯一标识并与其RTP媒体流关联。
For proper functionality, RTCP CNAMEs should be unique within the participants of an RTP session. However, the existing guidelines for choosing the RTCP CNAME provided in the RTP standard (RFC 3550) are insufficient to achieve this uniqueness. RFC 6222 was published to update those guidelines to allow endpoints to choose unique RTCP CNAMEs. Unfortunately, later investigations showed that some parts of the new algorithms were unnecessarily complicated and/or ineffective. This document addresses these concerns and replaces RFC 6222.
为了实现适当的功能，RTCP CNAMEs在RTP会话的参与者中应该是唯一的。然而，RTP标准（RFC 3550）中提供的选择RTCP CNAME的现有指南不足以实现这种唯一性。发布RFC 6222是为了更新这些指南，以允许端点选择唯一的RTCP CNAMEs。不幸的是，后来的调查表明，新算法的某些部分不必要地复杂和/或无效。本文件解决了这些问题，并取代了RFC 6222。
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/rfc7022.
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/rfc7022.
Copyright Notice
版权公告
Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2013 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. Introduction ....................................................2
2. Requirements Notation ...........................................3
3. Deficiencies with Earlier Guidelines for Choosing an
RTCP CNAME ......................................................3
4. Choosing an RTCP CNAME ..........................................4
4.1. Persistent RTCP CNAMEs versus Per-Session RTCP CNAMEs ......4
4.2. Requirements ...............................................5
5. Procedure to Generate a Unique Identifier .......................6
6. Security Considerations .........................................7
6.1. Considerations on Uniqueness of RTCP CNAMEs ................7
6.2. Session Correlation Based on RTCP CNAMEs ...................7
7. Acknowledgments .................................................8
8. References ......................................................8
8.1. Normative References .......................................8
8.2. Informative References .....................................8
1. Introduction ....................................................2
2. Requirements Notation ...........................................3
3. Deficiencies with Earlier Guidelines for Choosing an
RTCP CNAME ......................................................3
4. Choosing an RTCP CNAME ..........................................4
4.1. Persistent RTCP CNAMEs versus Per-Session RTCP CNAMEs ......4
4.2. Requirements ...............................................5
5. Procedure to Generate a Unique Identifier .......................6
6. Security Considerations .........................................7
6.1. Considerations on Uniqueness of RTCP CNAMEs ................7
6.2. Session Correlation Based on RTCP CNAMEs ...................7
7. Acknowledgments .................................................8
8. References ......................................................8
8.1. Normative References .......................................8
8.2. Informative References .....................................8
In Section 6.5.1 of [RFC3550], there are a number of recommendations for choosing a unique RTCP CNAME for an RTP endpoint. However, in practice, some of these methods are not guaranteed to produce a unique RTCP CNAME. [RFC6222] updated the guidelines for choosing RTCP CNAMEs, superseding those presented in Section 6.5.1 of [RFC3550]. Unfortunately, some parts of the new algorithms are rather complicated and also produce RTCP CNAMEs that, in some cases, are potentially linkable over multiple RTCP sessions even if a new RTCP CNAME is generated for each session. This document specifies a replacement for the algorithm in Section 5 of [RFC6222], which does not have this limitation and is also simpler to implement.
在[RFC3550]的第6.5.1节中，有许多关于为RTP端点选择唯一RTCP CNAME的建议。然而，在实践中，这些方法中的一些并不能保证生成唯一的RTCP CNAME。[RFC6222]更新了选择RTCP CNAMEs的指南，取代了[RFC3550]第6.5.1节中的指南。不幸的是，新算法的某些部分相当复杂，并且还会产生RTCP CNAME，在某些情况下，即使为每个会话生成新的RTCP CNAME，这些RTCP CNAME也可能在多个RTCP会话上链接。本文件规定了[RFC6222]第5节中算法的替代品，该算法没有此限制，且更易于实现。
For a discussion on the linkability of RTCP CNAMEs produced by [RFC6222], refer to [RESCORLA].
有关[RFC6222]生成的RTCP CNAME的可链接性的讨论，请参阅[RESCORLA]。
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“建议”、“不建议”、“可”和“可选”应按照[RFC2119]中的说明进行解释。
The recommendation in [RFC3550] is to generate an RTCP CNAME of the form "user@host" for multiuser systems, or "host" if the username is not available. The "host" part is specified to be the fully qualified domain name (FQDN) of the host from which the real-time data originates. While this guidance was appropriate at the time [RFC3550] was written, FQDNs are no longer necessarily unique and can sometimes be common across several endpoints in large service provider networks. This document replaces the use of the FQDN as an RTCP CNAME by alternative mechanisms.
[RFC3550]中的建议是生成以下格式的RTCP CNAME“user@host如果用户名不可用，则为“主机”。“主机”部分指定为实时数据来源主机的完全限定域名（FQDN）。虽然本指南在[RFC3550]编写时适用，但FQDN不再一定是唯一的，有时可能在大型服务提供商网络中的多个端点之间通用。本文档通过替代机制替代FQDN作为RTCP CNAME的使用。
IPv4 addresses are also suggested for use in RTCP CNAMEs in [RFC3550], where the "host" part of the RTCP CNAME is the numeric representation of the IPv4 address of the interface from which the RTP data originates. As noted in [RFC3550], the use of private network address space [RFC1918] can result in hosts having network addresses that are not globally unique. Additionally, this shared use of the same IPv4 address can occur with public IPv4 addresses if multiple hosts are assigned the same public IPv4 address and are connected to a Network Address Translation (NAT) device [RFC3022]. When multiple hosts share the same IPv4 address, whether private or public, using the IPv4 address as the RTCP CNAME leads to RTCP CNAMEs that are not necessarily unique.
[RFC3550]中还建议在RTCP CNAME中使用IPv4地址，其中RTCP CNAME的“主机”部分是RTP数据来源接口的IPv4地址的数字表示。如[RFC3550]所述，使用专用网络地址空间[RFC1918]可能导致主机的网络地址不是全局唯一的。此外，如果多个主机被分配了相同的公共IPv4地址并连接到网络地址转换（NAT）设备[RFC3022]，则相同IPv4地址的共享使用可能会与公共IPv4地址一起发生。当多台主机共享相同的IPv4地址（无论是专用还是公用）时，使用IPv4地址作为RTCP CNAME会导致RTCP CNAME不一定是唯一的。
It is also noted in [RFC3550] that if hosts with private addresses and no direct IP connectivity to the public Internet have their RTP packets forwarded to the public Internet through an RTP-level translator, they could end up having non-unique RTCP CNAMEs. The suggestion in [RFC3550] is that such applications provide a configuration option to allow the user to choose a unique RTCP CNAME; this technique puts the burden on the translator to translate RTCP CNAMEs from private addresses to public addresses if necessary to keep private addresses from being exposed. Experience has shown that this does not work well in practice.
[RFC3550]中还指出，如果具有专用地址且没有直接IP连接到公共互联网的主机通过RTP级转换器将其RTP数据包转发到公共互联网，则它们可能最终具有非唯一RTCP CNAME。[RFC3550]中的建议是，此类应用程序提供一个配置选项，允许用户选择唯一的RTCP CNAME；如果有必要防止私有地址被公开，这种技术会给翻译人员带来将RTCP CNAMEs从私有地址转换为公共地址的负担。经验表明，这在实践中并不奏效。
It is difficult, and in some cases impossible, for a host to determine if there is a NAT between itself and its RTP peer. Furthermore, even some public IPv4 addresses can be shared by multiple hosts in the Internet. Using the numeric representation of the IPv4 address as the "host" part of the RTCP CNAME is NOT RECOMMENDED.
主机很难确定自己和RTP对等机之间是否存在NAT，在某些情况下甚至不可能。此外，甚至一些公共IPv4地址也可以由Internet上的多个主机共享。不建议将IPv4地址的数字表示形式用作RTCP CNAME的“主机”部分。
The RTCP CNAME can be either persistent across different RTP sessions for an RTP endpoint or unique per session, meaning that an RTP endpoint chooses a different RTCP CNAME for each RTP session.
RTP CNAME可以在RTP端点的不同RTP会话中持久化，也可以在每个会话中唯一，这意味着RTP端点为每个RTP会话选择不同的RTCP CNAME。
An RTP endpoint that is emitting multiple related RTP streams that require synchronization at the other endpoint(s) MUST use the same RTCP CNAME for all streams that are to be synchronized. This requires a short-term, persistent RTCP CNAME that is common across several RTP streams, and potentially across several related RTP sessions. A common example of such use occurs when syncing audio and video streams in a multimedia session, where a single participant has to use the same RTCP CNAME for its audio RTP session and for its video RTP session. Another example might be to synchronize the layers of a layered audio codec, where the same RTCP CNAME has to be used for each layer.
发送多个相关RTP流（需要在其他端点进行同步）的RTP端点必须对所有要同步的流使用相同的RTCP CNAME。这需要一个短期、持久的RTCP CNAME，该CNAME在多个RTP流中通用，并且可能在多个相关RTP会话中通用。在多媒体会话中同步音频和视频流时会出现这种使用的常见示例，其中单个参与者必须为其音频RTP会话和视频RTP会话使用相同的RTCP CNAME。另一个示例可能是同步分层音频编解码器的层，其中每个层必须使用相同的RTCP CNAME。
If the multiple RTP streams in an RTP session are not related, and thus do not require synchronization, an RTP endpoint can use different RTCP CNAMEs for these streams.
如果RTP会话中的多个RTP流不相关，因此不需要同步，RTP端点可以对这些流使用不同的RTCP CNAME。
A longer-term persistent RTCP CNAME is sometimes useful to facilitate third-party monitoring, consistent with [RFC3550]. One such use might be to allow network management tools to correlate the ongoing quality of service for a participant across multiple RTP sessions for fault diagnosis and to understand long-term network performance statistics. An application developer that wishes to discourage this type of third-party monitoring can choose to generate a unique RTCP CNAME for each RTP session, or group of related RTP sessions, that the application will join. Such a per-session RTCP CNAME cannot be used for traffic analysis, and so provides some limited form of privacy. Note that there are non-RTP means that can be used by a third party to correlate RTP sessions, so the use of per-session RTCP CNAMEs will not prevent a determined traffic analyst from monitoring such sessions.
长期持久性RTCP CNAME有时有助于促进第三方监控，符合[RFC3550]。其中一个用途可能是允许网络管理工具将参与者在多个RTP会话中的持续服务质量关联起来进行故障诊断，并了解长期网络性能统计数据。希望阻止此类第三方监控的应用程序开发人员可以选择为应用程序将加入的每个RTP会话或相关RTP会话组生成唯一的RTCP CNAME。这样的每会话RTCP CNAME不能用于流量分析，因此提供了一些有限形式的隐私。请注意，第三方可以使用非RTP方式关联RTP会话，因此使用每会话RTCP CNAMEs不会阻止已确定的流量分析师监控此类会话。
This memo defines several different ways by which an implementation can choose an RTCP CNAME. It is possible, and legitimate, for independent implementations to make different choices of RTCP CNAME when running on the same host. This can hinder third-party monitoring, unless some external means is provided to configure a persistent choice of RTCP CNAME for those implementations.
本备忘录定义了实现选择RTCP CNAME的几种不同方式。在同一台主机上运行时，独立实现对RTCP CNAME进行不同选择是可能的，也是合法的。这可能会妨碍第三方监控，除非提供一些外部手段来为这些实现配置RTCP CNAME的持久选择。
Note that there is no backwards compatibility issue (with implementations compatible with [RFC3550]) introduced in this memo, since the RTCP CNAMEs are opaque strings to remote peers.
请注意，由于RTCP CNAME对于远程对等方来说是不透明的字符串，因此本备忘录中没有引入向后兼容性问题（与[RFC3550]兼容的实现）。
RTP endpoints will choose to generate RTCP CNAMEs that are persistent or per-session. An RTP endpoint that wishes to generate a persistent RTCP CNAME MUST use one of the following two methods:
RTP端点将选择生成持久或每个会话的RTCP CNAME。希望生成持久RTCP CNAME的RTP端点必须使用以下两种方法之一：
o To produce a long-term persistent RTCP CNAME, an RTP endpoint MUST generate and store a Universally Unique IDentifier (UUID) [RFC4122] for use as the "host" part of its RTCP CNAME. The UUID MUST be version 1, 2, or 4, as described in [RFC4122], with the "urn:uuid:" stripped, resulting in a 36-octet printable string representation.
o 要生成长期持久的RTCP CNAME，RTP端点必须生成并存储一个通用唯一标识符（UUID）[RFC4122]以用作其RTCP CNAME的“主机”部分。UUID必须是版本1、2或4，如[RFC4122]中所述，去掉“urn:UUID:”，从而得到36个八位字节的可打印字符串表示形式。
o To produce a short-term persistent RTCP CNAME, an RTP endpoint MUST generate and use an identifier by following the procedure described in Section 5. That procedure is performed at least once per initialization of the software. After obtaining an identifier, minimally the least significant 96 bits SHOULD be converted to ASCII using Base64 encoding [RFC4648] (to compromise between packet size and uniqueness -- refer to Section 6.1). If 96 bits are used, the resulting string will be 16 octets. Note the Base64 encoded value cannot exceed the maximum RTCP CNAME length of 255 octets [RFC3550].
o 要生成短期持久RTCP CNAME，RTP端点必须按照第5节中描述的过程生成并使用标识符。该程序在每次软件初始化时至少执行一次。获得标识符后，最低有效96位应使用Base64编码[RFC4648]转换为ASCII（以在数据包大小和唯一性之间折衷——请参阅第6.1节）。如果使用96位，结果字符串将为16个八位字节。注：Base64编码值不能超过最大RTCP CNAME长度255个八位字节[RFC3550]。
In the two cases above, the "user@" part of the RTCP CNAME MAY be omitted on single-user systems and MAY be replaced by an opaque token on multiuser systems, to preserve privacy.
在上述两种情况下，RTCP CNAME的“用户@”部分在单用户系统上可以省略，在多用户系统上可以用不透明令牌替换，以保护隐私。
An RTP endpoint that wishes to generate a per-session RTCP CNAME MUST use the following method:
希望生成每会话RTCP CNAME的RTP终结点必须使用以下方法：
o For every new RTP session, a new RTCP CNAME is generated following the procedure described in Section 5. After performing that procedure, minimally the least significant 96 bits SHOULD be converted to ASCII using Base64 encoding [RFC4648]. The RTCP
o 对于每个新的RTP会话，按照第5节中描述的过程生成一个新的RTCP CNAME。执行该过程后，最低有效96位应使用Base64编码[RFC4648]转换为ASCII。RTCP
CNAME cannot change over the life of an RTP session [RFC3550]. The "user@" part of the RTCP CNAME is omitted when generating per-session RTCP CNAMEs.
CNAME不能在RTP会话[RFC3550]的生命周期内更改。生成每个会话的RTCP CNAME时，RTCP CNAME的“用户@”部分被省略。
It is believed that obtaining uniqueness (with a high probability) is an important property that requires careful evaluation of the method. This document provides a number of methods, at least one of which would be suitable for any given deployment scenarios. This document therefore does not provide for the implementor to define and select an alternative method.
人们认为，获得唯一性（高概率）是一个重要的特性，需要仔细评估该方法。本文档提供了许多方法，其中至少有一种适用于任何给定的部署场景。因此，本文件不允许实施者定义和选择替代方法。
A future specification might define an alternative method for generating RTCP CNAMEs, as long as the proposed method has appropriate uniqueness and there is consistency between the methods used for multiple RTP sessions that are to be correlated. However, such a specification needs to be reviewed and approved before deployment.
未来的规范可能会定义生成RTCP CNAME的替代方法，只要所提出的方法具有适当的唯一性，并且用于将要关联的多个RTP会话的方法之间存在一致性。但是，在部署之前需要对此类规范进行审查和批准。
The mechanisms described in this document are to be used to generate RTCP CNAMEs, and they are not to be used for generating general-purpose unique identifiers.
本文件中描述的机制用于生成RTCP CNAMEs，不用于生成通用唯一标识符。
To locally produce a unique identifier, one simply generates a cryptographically pseudorandom value as described in [RFC4086]. This value MUST be at least 96 bits.
要在本地生成唯一标识符，只需生成[RFC4086]中所述的加密伪随机值。此值必须至少为96位。
The biggest bottleneck to implementation of this algorithm is the availability of an appropriate cryptographically secure pseudorandom number generator (CSPRNG). In any setting that already has a secure PRNG, this algorithm described is far simpler than the algorithm described in Section 5 of [RFC6222]. SIP stacks [RFC3261] are required to use cryptographically random numbers to generate To and From tags (Section 19.3). Real-Time Communications on the Web (RTCWEB) implementations [ARCH] will need to have secure PRNGs to implement ICE [RFC5245] and DTLS-SRTP [RFC5764]. And, of course, essentially every Web browser already supports TLS, which requires a secure PRNG.
实现该算法的最大瓶颈是适当的加密安全伪随机数生成器（CSPRNG）的可用性。在已经具有安全PRNG的任何设置中，所述算法远比[RFC6222]第5节中所述的算法简单。SIP堆栈[RFC3261]需要使用加密随机数来生成标记（第19.3节）。网络实时通信（RTCWEB）实现[ARCH]需要有安全的PRNG来实现ICE[RFC5245]和DTLS-SRTP[RFC5764]。当然，基本上每个Web浏览器都已经支持TLS，这需要一个安全的PRNG。
The security considerations of [RFC3550] apply to this memo.
[RFC3550]的安全注意事项适用于本备忘录。
The considerations in this section apply to random RTCP CNAMEs.
本节中的注意事项适用于随机RTCP CNAMEs。
The recommendations given in this document for RTCP CNAME generation ensure that a set of cooperating participants in an RTP session will, with very high probability, have unique RTCP CNAMEs. However, neither [RFC3550] nor this document provides any way to ensure that participants will choose RTCP CNAMEs appropriately; thus, implementations MUST NOT rely on the uniqueness of RTCP CNAMEs for any essential security services. This is consistent with [RFC3550], which does not require that RTCP CNAMEs are unique within a session but instead says that condition SHOULD hold. As described in the Security Considerations section of [RFC3550], because each participant in a session is free to choose its own RTCP CNAME, they can do so in such a way as to impersonate another participant. That is, participants are trusted not to impersonate each other. No recommendation for generating RTCP CNAMEs can prevent this impersonation, because an attacker can neglect the stipulation. Secure RTP (SRTP) [RFC3711] keeps unauthorized entities out of an RTP session, but it does not aim to prevent impersonation attacks from authorized entities.
本文件中给出的RTCP CNAME生成建议确保RTP会话中的一组合作参与者很可能具有唯一的RTCP CNAME。然而，[RFC3550]和本文件均未提供任何方式确保参与者适当选择RTCP CNAMEs；因此，对于任何基本的安全服务，实现都不能依赖RTCP CNAMEs的唯一性。这与[RFC3550]一致，后者不要求RTCP CNAMEs在会话中是唯一的，而是说该条件应保持不变。如[RFC3550]的“安全注意事项”部分所述，由于会话中的每个参与者都可以自由选择自己的RTCP CNAME，因此他们可以模仿其他参与者。也就是说，参与者被信任不会相互模仿。生成RTCP CNAMEs的任何建议都不能防止这种模拟，因为攻击者可以忽略该规定。安全RTP（SRTP）[RFC3711]将未经授权的实体排除在RTP会话之外，但其目的不是防止来自授权实体的模拟攻击。
Because of the properties of the PRNG, there is no significant privacy/linkability difference between long and short RTCP CNAMEs. However, the requirement to generate unique RTCP CNAMEs implies a certain minimum length. A length of 96 bits allows on the order of 2^{40} RTCP CNAMEs globally before there is a large chance of collision (there is about a 50% chance of one collision after 2^{48} RTCP CNAMEs).
由于PRNG的特性，长RTCP CNAME和短RTCP CNAME之间没有明显的隐私/链接性差异。但是，生成唯一RTCP CNAMEs的要求意味着一定的最小长度。96位的长度允许在发生较大冲突的可能性之前全局范围内达到2^{40}RTCP CNAMEs的数量级（在2^{48}RTCP CNAMEs之后发生一次冲突的概率约为50%）。
Earlier recommendations for RTCP CNAME generation allowed a fixed RTCP CNAME value, which allows an attacker to easily link separate RTP sessions, eliminating the obfuscation provided by IPv6 privacy addresses [RFC4941] or IPv4 Network Address Port Translation (NAPT) [RFC3022].
早期的RTCP CNAME生成建议允许使用固定的RTCP CNAME值，这使得攻击者能够轻松链接单独的RTP会话，从而消除IPv6隐私地址[RFC4941]或IPv4网络地址端口转换（NAPT）[RFC3022]提供的混淆。
This specification no longer describes a procedure to generate fixed RTCP CNAME values, so RTCP CNAME values no longer provide such linkage between RTP sessions. This was necessary to eliminate such
本规范不再描述生成固定RTCP CNAME值的过程，因此RTCP CNAME值不再提供RTP会话之间的此类链接。这对于消除这种情况是必要的
linking by an attacker, but of course complicates linking by traffic analysis devices (e.g., devices that are looking for dropped or delayed packets).
由攻击者链接，但当然会使流量分析设备（例如，查找丢弃或延迟数据包的设备）的链接复杂化。
Thanks to Marc Petit-Huguenin, who suggested using UUIDs in generating RTCP CNAMEs. Also, thanks to David McGrew for providing text for the Security Considerations section in RFC 6222.
感谢Marc Petit Huguein，他建议在生成RTCP CNAMEs时使用UUID。另外，感谢David McGrew为RFC 6222中的安全注意事项部分提供文本。
[RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V. Jacobson, "RTP: A Transport Protocol for Real-Time Applications", STD 64, RFC 3550, July 2003.
[RFC3550]Schulzrinne，H.，Casner，S.，Frederick，R.，和V.Jacobson，“RTP：实时应用的传输协议”，STD 64，RFC 35502003年7月。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally Unique IDentifier (UUID) URN Namespace", RFC 4122, July 2005.
[RFC4122]Leach，P.，Mealling，M.和R.Salz，“通用唯一标识符（UUID）URN名称空间”，RFC 4122，2005年7月。
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings", RFC 4648, October 2006.
[RFC4648]Josefsson，S.，“Base16、Base32和Base64数据编码”，RFC4648，2006年10月。
[RFC4086] Eastlake, D., Schiller, J., and S. Crocker, "Randomness Requirements for Security", BCP 106, RFC 4086, June 2005.
[RFC4086]Eastlake，D.，Schiller，J.，和S.Crocker，“安全的随机性要求”，BCP 106，RFC 4086，2005年6月。
[RFC6222] Begen, A., Perkins, C., and D. Wing, "Guidelines for Choosing RTP Control Protocol (RTCP) Canonical Names (CNAMEs)", RFC 6222, April 2011.
[RFC6222]Begen，A.，Perkins，C.，和D.Wing，“选择RTP控制协议（RTCP）规范名称（CNAMEs）的指南”，RFC 6222，2011年4月。
[RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and E. Lear, "Address Allocation for Private Internets", BCP 5, RFC 1918, February 1996.
[RFC1918]Rekhter，Y.，Moskowitz，R.，Karrenberg，D.，Groot，G.，和E.Lear，“私人互联网地址分配”，BCP 5，RFC 1918，1996年2月。
[RFC3022] Srisuresh, P. and K. Egevang, "Traditional IP Network Address Translator (Traditional NAT)", RFC 3022, January 2001.
[RFC3022]Srisuresh，P.和K.Egevang，“传统IP网络地址转换器（传统NAT）”，RFC 3022，2001年1月。
[RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K. Norrman, "The Secure Real-time Transport Protocol (SRTP)", RFC 3711, March 2004.
[RFC3711]Baugher，M.，McGrew，D.，Naslund，M.，Carrara，E.，和K.Norrman，“安全实时传输协议（SRTP）”，RFC 37112004年3月。
[RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy Extensions for Stateless Address Autoconfiguration in IPv6", RFC 4941, September 2007.
[RFC4941]Narten，T.，Draves，R.，和S.Krishnan，“IPv6中无状态地址自动配置的隐私扩展”，RFC 49412007年9月。
[RFC5245] Rosenberg, J., "Interactive Connectivity Establishment (ICE): A Protocol for Network Address Translator (NAT) Traversal for Offer/Answer Protocols", RFC 5245, April 2010.
[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 52452010年4月。
[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, May 2010.
[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 5764，2010年5月。
[RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, June 2002.
[RFC3261]Rosenberg，J.，Schulzrinne，H.，Camarillo，G.，Johnston，A.，Peterson，J.，Sparks，R.，Handley，M.，和E.Schooler，“SIP：会话启动协议”，RFC 3261，2002年6月。
[ARCH] Rescorla, E., "WebRTC Security Architecture", Work in Progress, July 2013.
[ARCH]Rescorla，E.，“WebRTC安全架构”，正在进行的工作，2013年7月。
[RESCORLA] Rescorla, E., "Random algorithm for RTP CNAME generation", Work in Progress, July 2012.
[RESCORLA]RESCORLA，E.，“RTP CNAME生成的随机算法”，正在进行的工作，2012年7月。
Authors' Addresses
作者地址
Ali Begen Cisco 181 Bay Street Toronto, ON M5J 2T3 CANADA
Ali Begen Cisco位于加拿大多伦多湾街181号M5J 2T3
EMail: abegen@cisco.com
EMail: abegen@cisco.com
Colin Perkins University of Glasgow School of Computing Science Glasgow G12 8QQ UK
柯林帕金斯格拉斯哥大学计算科学学院格拉斯哥G128QQ英国
EMail: csp@csperkins.org
EMail: csp@csperkins.org
Dan Wing Cisco Systems, Inc. 170 West Tasman Drive San Jose, California 95134 USA
Dan Wing Cisco Systems，Inc.美国加利福尼亚州圣何塞西塔斯曼大道170号，邮编95134
EMail: dwing@cisco.com
EMail: dwing@cisco.com
Eric Rescorla RTFM, Inc. 2064 Edgewood Drive Palo Alto, CA 94303 USA
Eric Rescorla RTFM，Inc.美国加利福尼亚州帕洛阿尔托埃奇伍德大道2064号，邮编94303
Phone: +1 650 678 2350
EMail: ekr@rtfm.com
Phone: +1 650 678 2350
EMail: ekr@rtfm.com