Internet Engineering Task Force (IETF) J. Haas
Request for Comments: 7300 Juniper Networks
BCP: 6 J. Mitchell
Updates: 1930 Microsoft Corporation
Category: Best Current Practice July 2014
ISSN: 2070-1721
Internet Engineering Task Force (IETF) J. Haas
Request for Comments: 7300 Juniper Networks
BCP: 6 J. Mitchell
Updates: 1930 Microsoft Corporation
Category: Best Current Practice July 2014
ISSN: 2070-1721
Reservation of Last Autonomous System (AS) Numbers
保留最后一个自治系统（AS）编号
Abstract
摘要
This document reserves two Autonomous System Numbers (ASNs) at the end of the 16-bit and 32-bit ranges, described in this document as "Last ASNs", and provides guidance to implementers and operators on their use. This document updates Section 10 of RFC 1930.
本文件在16位和32位范围的末尾保留了两个自主系统编号（ASN），在本文件中称为“最后一个ASN”，并为实施者和操作员提供使用指南。本文件更新了RFC 1930第10节。
Status of This Memo
关于下段备忘
This memo documents an Internet Best Current Practice.
本备忘录记录了互联网最佳实践。
This document is a product of the Internet Engineering Task Force (IETF). It has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on BCPs is available in Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。互联网工程指导小组（IESG）已批准将其出版。有关BCP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/rfc7300.
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/rfc7300.
Copyright Notice
版权公告
Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2014 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。
Over a decade ago, IANA reserved the last Autonomous System Number (ASN) of the 16-bit ASN range, 65535, with the intention that it not be used by network operators running BGP [RFC4271]. Since the introduction of "BGP Support for Four-Octet Autonomous System (AS) Number Space" [RFC6793], IANA has also reserved the last ASN of the 32-bit autonomous system number range, 4294967295. This reservation has been documented in the IANA "Autonomous System (AS) Numbers" registry [IANA.AS]. Although these "Last ASNs" border on Private Use ASN [RFC6996] ranges, they are not defined or reserved as Private Use ASNs by [IANA.AS]. This document describes the reasoning for reserving Last ASNs and provides guidance both to operators and to implementers on their use.
十多年前，IANA保留了16位ASN范围的最后一个自治系统号（ASN），即65535，目的是不让运行BGP[RFC4271]的网络运营商使用。自从引入“BGP支持四个八位组自治系统（AS）编号空间”[RFC6793]以来，IANA还保留了32位自治系统编号范围的最后一个ASN，即4294967295。该保留已记录在IANA“自主系统（AS）编号”注册表[IANA.AS]中。尽管这些“最后一个ASN”位于专用ASN[RFC6996]范围内，但[IANA.as]并未将其定义或保留为专用ASN。本文档描述了保留最后一个ASN的原因，并为操作员和实施者提供了使用指南。
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。
A subset of the BGP communities of ASN 65535, the last ASN of the 16-bit range, are reserved for use by Well-known Communities as described in [RFC1997] and [IANA.WK]. Although this is not currently true of ASN 4294967295, if there is a future need for another Special Use ASN that is not designed to be globally routable, or for the associated BGP communities of such an ASN, ASN 4294967295 could be a valid candidate for such purpose. This document does not prescribe any such Special Use to this ASN at the time of publication.
如[RFC1997]和[IANA.WK]所述，ASN 65535（16位范围内的最后一个ASN）的BGP社区的一个子集保留供知名社区使用。尽管ASN 4294967295目前并非如此，但如果未来需要另一种特殊用途的ASN，而该ASN的设计不是全球可路由的，或者是此类ASN的相关BGP社区，ASN 4294967295可能是此类用途的有效候选。本文件在发布时未规定本ASN的任何此类特殊用途。
Operators SHOULD NOT use these Last ASNs for any other purpose or as Private Use ASNs. Operational use of these Last ASNs could have undesirable results. For example; use of AS 65535 as if it were a Private Use ASN, may result in inadvertent use of BGP Well-known Community values [IANA.WK], causing undesirable routing behavior.
运营商不应将这些最后的ASN用于任何其他目的或作为私人使用的ASN。最后这些ASN的操作使用可能会产生不良结果。例如将AS 65535当作专用ASN使用可能会导致无意中使用BGP已知社区值[IANA.WK]，从而导致不良路由行为。
Last ASNs MUST NOT be advertised to the global Internet within AS_PATH or AS4_PATH attributes. Operators SHOULD filter Last ASNs within the AS_PATH and AS4_PATH attributes.
最后一个ASN不得在AS_路径或AS4_路径属性中发布到全球互联网。操作员应过滤AS_路径和AS4_路径属性中的最后一个ASN。
While Last ASNs are reserved, they remain valid ASNs from a BGP perspective. Therefore, implementations of BGP [RFC4271] SHOULD NOT treat the use of Last ASNs as any type of protocol error. However, if a Last ASN is configured as the local AS, implementations MAY generate a warning message indicating improper use of a reserved ASN.
虽然保留了最后一个ASN，但从BGP的角度来看，它们仍然是有效的ASN。因此，BGP[RFC4271]的实现不应将最后一个ASN的使用视为任何类型的协议错误。但是，如果将最后一个ASN配置为本地as，则实现可能会生成一条警告消息，指示不正确使用保留ASN。
Implementations that provide tools that filter Private Use ASNs within the AS_PATH and AS4_PATH attributes MAY also include Last ASNs.
提供在AS_路径和AS4_路径属性中过滤专用ASN的工具的实现也可能包括最后一个ASN。
IANA has reserved last Autonomous System number 65535 from the "16-bit Autonomous System Numbers" registry for the reasons described in this document.
出于本文件所述原因，IANA已从“16位自治系统编号”注册表中保留最后一个自治系统编号65535。
IANA has also reserved last Autonomous System number 4294967295 from the "32-bit Autonomous System Numbers" registry for the reasons described in this document.
出于本文件所述原因，IANA还从“32位自治系统编号”注册表中保留了最后一个自治系统编号4294967295。
These reservations have been documented in the IANA "Autonomous System (AS) Numbers" registry [IANA.AS] and the IANA "Special-Purpose Autonomous System (AS) Numbers" registry [IANA.SpecialAS].
这些保留已记录在IANA“自治系统（AS）编号”注册表[IANA.AS]和IANA“专用自治系统（AS）编号”注册表[IANA.SpecialAS]中。
This document does not introduce any additional security concerns in regards to usage of Last ASNs. Although the BGP is designed to allow usage of Last ASNs, security issues related to BGP implementation errors could be triggered by Last ASN usage.
本文件并未就最后一个ASN的使用引入任何额外的安全问题。虽然BGP的设计允许使用最后一个ASN，但最后一个ASN的使用可能会触发与BGP实施错误相关的安全问题。
[IANA.AS] IANA, "Autonomous System (AS) Numbers", <http://www.iana.org/assignments/as-numbers/>.
[IANA.AS]IANA，“自主系统（AS）编号”<http://www.iana.org/assignments/as-numbers/>.
[IANA.SpecialAS] IANA, "Special-Purpose Autonomous System (AS) Numbers", <http://www.iana.org/assignments/ iana-as-numbers-special-registry/>.
[IANA.SpecialAS]IANA，“专用自治系统（AS）编号”<http://www.iana.org/assignments/ iana as编号特别注册表/>。
[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。
[RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, January 2006.
[RFC4271]Rekhter，Y.，Li，T.，和S.Hares，“边境网关协议4（BGP-4）”，RFC 42712006年1月。
[RFC6793] Vohra, Q. and E. Chen, "BGP Support for Four-Octet Autonomous System (AS) Number Space", RFC 6793, December 2012.
[RFC6793]Vohra，Q.和E.Chen，“BGP对四个八位组自治系统（AS）数字空间的支持”，RFC 6793，2012年12月。
[IANA.WK] IANA, "Border Gateway Protocol (BGP) Well-known Communities", <http://www.iana.org/assignments/ bgp-well-known-communities/>.
[IANA.WK]IANA，“边界网关协议（BGP）知名社区”<http://www.iana.org/assignments/ bgp知名社区/>。
[RFC1997] Chandrasekeran, R., Traina, P., and T. Li, "BGP Communities Attribute", RFC 1997, August 1996.
[RFC1997]Chandrasekeran，R.，Traina，P.，和T.Li，“BGP社区属性”，RFC 1997，1996年8月。
[RFC6996] Mitchell, J., "Autonomous System (AS) Reservation for Private Use", BCP 6, RFC 6996, July 2013.
[RFC6996]Mitchell，J.，“供私人使用的自主系统（AS）预订”，BCP 6，RFC 69962013年7月。
The authors would like to thank Michelle Cotton and Elwyn Davies for encouraging the proper documentation of the reservation of these ASNs, and David Farmer for his contributions to the document.
作者要感谢米歇尔·科顿（Michelle Cotton）和埃尔温·戴维斯（Elwyn Davies）鼓励正确记录这些ASN的保留地，并感谢大卫·法默（David Farmer）对该文件的贡献。
Authors' Addresses
作者地址
Jeffrey Haas Juniper Networks
Jeffrey Haas Juniper网络
EMail: jhaas@juniper.net
EMail: jhaas@juniper.net
Jon Mitchell Microsoft Corporation One Microsoft Way Redmond, WA 98052 USA
Jon Mitchell微软公司美国华盛顿州雷德蒙微软大道一号，邮编：98052
EMail: Jon.Mitchell@microsoft.com
EMail: Jon.Mitchell@microsoft.com