Internet Engineering Task Force (IETF) L. Ginsberg
Request for Comments: 7883 Cisco Systems
Category: Standards Track N. Akiya
ISSN: 2070-1721 Big Switch Networks
M. Chen
Huawei
July 2016
Internet Engineering Task Force (IETF) L. Ginsberg
Request for Comments: 7883 Cisco Systems
Category: Standards Track N. Akiya
ISSN: 2070-1721 Big Switch Networks
M. Chen
Huawei
July 2016
Advertising Seamless Bidirectional Forwarding Detection (S-BFD) Discriminators in IS-IS
IS-IS中的广告无缝双向转发检测（S-BFD）鉴别器
Abstract
摘要
This document defines a means of advertising one or more Seamless Bidirectional Forwarding Detection (S-BFD) Discriminators using the IS-IS Router CAPABILITY TLV.
本文档定义了使用IS-IS路由器功能TLV宣传一个或多个无缝双向转发检测（S-BFD）鉴别器的方法。
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 7841.
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 7841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/rfc7883.
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/rfc7883.
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。
This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English.
本文件可能包含2008年11月10日之前发布或公开的IETF文件或IETF贡献中的材料。控制某些材料版权的人员可能未授予IETF信托允许在IETF标准流程之外修改此类材料的权利。在未从控制此类材料版权的人员处获得充分许可的情况下，不得在IETF标准流程之外修改本文件，也不得在IETF标准流程之外创建其衍生作品，除了将其格式化以RFC形式发布或将其翻译成英语以外的其他语言。
Table of Contents
目录
1. Introduction ....................................................3
2. Encoding Format .................................................3
3. IANA Considerations .............................................4
4. Security Considerations .........................................4
5. Normative References ............................................4
Acknowledgements ...................................................5
Authors' Addresses .................................................5
1. Introduction ....................................................3
2. Encoding Format .................................................3
3. IANA Considerations .............................................4
4. Security Considerations .........................................4
5. Normative References ............................................4
Acknowledgements ...................................................5
Authors' Addresses .................................................5
[RFC7880] defines a simplified mechanism for using Bidirectional Forwarding Detection (BFD) [RFC5880]. This mechanism depends on network nodes knowing the BFD Discriminators that each node in the network has reserved for this purpose. The use of the Intermediate System to Intermediate System (IS-IS) [IS-IS] protocol is one possible means of advertising these discriminators.
[RFC7880]定义了使用双向转发检测（BFD）的简化机制[RFC5880]。此机制取决于网络节点是否知道网络中的每个节点为此目的保留的BFD鉴别器。使用中间系统到中间系统（IS-IS）[IS-IS]协议是宣传这些鉴别器的一种可能方式。
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 IS-IS Router CAPABILITY TLV as defined in [RFC4971] will be used to advertise Seamless BFD (S-BFD) Discriminators. A new sub-TLV is defined as described below. S-BFD Discriminators sub-TLVs are formatted as specified in [RFC5305].
[RFC4971]中定义的IS-IS路由器功能TLV将用于宣传无缝BFD（S-BFD）鉴别器。新的子TLV定义如下所述。S-BFD鉴别器子TLV按照[RFC5305]中的规定进行格式化。
No. of octets
+-----------------------------+
| Type (20) | 1
+-----------------------------+
| Length (multiple of 4) | 1
+-----------------------------+
| Discriminator Value(s) | 4/Discriminator
: :
+-----------------------------+
No. of octets
+-----------------------------+
| Type (20) | 1
+-----------------------------+
| Length (multiple of 4) | 1
+-----------------------------+
| Discriminator Value(s) | 4/Discriminator
: :
+-----------------------------+
The inclusion of an S-BFD Discriminators sub-TLV in a Router CAPABILITY TLV is optional. Multiple S-BFD Discriminators sub-TLVs MAY be advertised by an IS. How a given discriminator is mapped to a specific use case when multiple S-BFD Discriminators are advertised is out of scope for this document.
在路由器功能TLV中包含S-BFD鉴别器子TLV是可选的。IS可以通告子TLV的多个S-BFD鉴别器。当发布多个S-BFD鉴别器时，给定鉴别器如何映射到特定用例超出了本文档的范围。
S-BFD Discriminator advertisements MAY be flooded within an area or throughout the domain, using the procedures specified in [RFC4971]. The appropriate flooding scope depends on the intended use of S-BFD. If S-BFD usage will be exclusively within a Level-1 area, then area scope is appropriate. If S-BFD usage will span different Level-1 areas, then domain scope is appropriate.
使用[RFC4971]中规定的程序，S-BFD鉴别器广告可能会淹没在某个区域内或整个域内。适当的注水范围取决于S-BFD的预期用途。如果S-BFD仅在一级区域内使用，则区域范围是合适的。如果S-BFD的使用将跨越不同的1级区域，则域范围是合适的。
IANA has added a new sub-TLV in the "Sub-TLVs for TLV 242" registry. The registration is as follows:
IANA在“TLV 242的子TLV”注册表中添加了一个新的子TLV。登记情况如下：
Value Description
----- --------------------
20 S-BFD Discriminators
Value Description
----- --------------------
20 S-BFD Discriminators
Security concerns for IS-IS are addressed in [IS-IS], [RFC5304], and [RFC5310]. The new S-BFD Discriminators sub-TLV does not introduce any new security risks for IS-IS.
IS-IS的安全问题在[IS-IS]、[RFC5304]和[RFC5310]中有说明。新的S-BFD鉴别器子TLV不会给IS-IS带来任何新的安全风险。
Advertising the S-BFD Discriminators makes it possible for attackers to initiate S-BFD sessions using the advertised information. The vulnerabilities this poses and how to mitigate them are discussed in [RFC7880].
公布S-BFD鉴别器使攻击者能够使用公布的信息启动S-BFD会话。[RFC7880]中讨论了由此造成的漏洞以及如何缓解这些漏洞。
[IS-IS] International Organization for Standardization, "Intermediate System to Intermediate System intra-domain routeing information exchange protocol for use in conjunction with the protocol for providing the connectionless-mode network service (ISO 8473)", ISO Standard 10589, 2002.
[IS-IS]国际标准化组织，“与提供无连接模式网络服务协议一起使用的中间系统到中间系统域内路由信息交换协议（ISO 8473）”，ISO标准10589，2002年。
[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>.
[RFC4971] Vasseur, JP., Ed., Shen, N., Ed., and R. Aggarwal, Ed., "Intermediate System to Intermediate System (IS-IS) Extensions for Advertising Router Information", RFC 4971, DOI 10.17487/RFC4971, July 2007, <http://www.rfc-editor.org/info/rfc4971>.
[RFC4971]Vasseur，JP.，Ed.，Shen，N.，Ed.，和R.Aggarwal，Ed.，“广告路由器信息的中间系统到中间系统（IS-IS）扩展”，RFC 4971，DOI 10.17487/RFC4971，2007年7月<http://www.rfc-editor.org/info/rfc4971>.
[RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic Authentication", RFC 5304, DOI 10.17487/RFC5304, October 2008, <http://www.rfc-editor.org/info/rfc5304>.
[RFC5304]Li，T.和R.Atkinson，“IS-IS加密认证”，RFC 5304，DOI 10.17487/RFC5304，2008年10月<http://www.rfc-editor.org/info/rfc5304>.
[RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic Engineering", RFC 5305, DOI 10.17487/RFC5305, October 2008, <http://www.rfc-editor.org/info/rfc5305>.
[RFC5305]Li，T.和H.Smit，“交通工程的IS-IS扩展”，RFC 5305，DOI 10.17487/RFC5305，2008年10月<http://www.rfc-editor.org/info/rfc5305>.
[RFC5310] Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R., and M. Fanto, "IS-IS Generic Cryptographic Authentication", RFC 5310, DOI 10.17487/RFC5310, February 2009, <http://www.rfc-editor.org/info/rfc5310>.
[RFC5310]Bhatia，M.，Manral，V.，Li，T.，Atkinson，R.，White，R.，和M.Fanto，“IS-IS通用密码认证”，RFC 5310，DOI 10.17487/RFC5310，2009年2月<http://www.rfc-editor.org/info/rfc5310>.
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010, <http://www.rfc-editor.org/info/rfc5880>.
[RFC5880]Katz，D.和D.Ward，“双向转发检测（BFD）”，RFC 5880，DOI 10.17487/RFC5880，2010年6月<http://www.rfc-editor.org/info/rfc5880>.
[RFC7880] Pignataro, C., Ward, D., Akiya, N., Bhatia, M., and S. Pallagatti, "Seamless Bidirectional Forwarding Detection (S-BFD)", RFC 7880, DOI 10.17487/RFC7880, July 2016, <http://www.rfc-editor.org/info/rfc7880>.
[RFC7880]Pignataro，C.，Ward，D.，Akiya，N.，Bhatia，M.，和S.Pallagati，“无缝双向转发检测（S-BFD）”，RFC 7880，DOI 10.17487/RFC78802016年7月<http://www.rfc-editor.org/info/rfc7880>.
Acknowledgements
致谢
The authors wish to thank Sam Aldrin, Manav Bhatia, and Carlos Pignataro for input essential to defining the needed functionality.
作者希望感谢Sam Aldrin、Manav Bhatia和Carlos Pignataro为定义所需功能所做的必要输入。
Authors' Addresses
作者地址
Les Ginsberg Cisco Systems 510 McCarthy Blvd. Milpitas, CA 95035 United States of America
莱斯金斯伯格思科系统公司，麦卡锡大道510号。美国加利福尼亚州米尔皮塔斯95035
Email: ginsberg@cisco.com
Email: ginsberg@cisco.com
Nobo Akiya Big Switch Networks
Nobo Akiya大交换网络
Email: nobo.akiya.dev@gmail.com
Email: nobo.akiya.dev@gmail.com
Mach(Guoyi) Chen Huawei
马赫（国一）陈华为
Email: mach.chen@huawei.com
Email: mach.chen@huawei.com