Internet Engineering Task Force (IETF) R. Aggarwal
Request for Comments: 5786 K. Kompella
Updates: 3630 Juniper Networks
Category: Standards Track March 2010
ISSN: 2070-1721
Internet Engineering Task Force (IETF) R. Aggarwal
Request for Comments: 5786 K. Kompella
Updates: 3630 Juniper Networks
Category: Standards Track March 2010
ISSN: 2070-1721
Advertising a Router's Local Addresses in OSPF Traffic Engineering (TE) Extensions
在OSPF流量工程（TE）扩展中公布路由器的本地地址
Abstract
摘要
OSPF Traffic Engineering (TE) extensions are used to advertise TE Link State Advertisements (LSAs) containing information about TE-enabled links. The only addresses belonging to a router that are advertised in TE LSAs are the local addresses corresponding to TE-enabled links, and the local address corresponding to the Router ID.
OSPF流量工程（TE）扩展用于通告TE链路状态通告（LSA），其中包含有关启用TE的链路的信息。在TE LSA中通告的属于路由器的唯一地址是与TE启用链接对应的本地地址，以及与路由器ID对应的本地地址。
In order to allow other routers in a network to compute Multiprotocol Label Switching (MPLS) Traffic Engineered Label Switched Paths (TE LSPs) to a given router's local addresses, those addresses must also be advertised by OSPF TE.
为了允许网络中的其他路由器计算到给定路由器本地地址的多协议标签交换（MPLS）流量工程标签交换路径（TE LSP），这些地址还必须由OSPF TE公布。
This document describes procedures that enhance OSPF TE to advertise a router's local addresses.
本文档描述了增强OSPF TE以公布路由器本地地址的过程。
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/rfc5786.
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/rfc5786.
Copyright Notice
版权公告
Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2010 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
1.1. Motivation .................................................3
2. Specification of Requirements ...................................3
3. Rejected Potential Solution .....................................4
4. Solution ........................................................4
4.1. Node Attribute TLV .........................................4
4.2. Operation ..................................................5
5. Security Considerations .........................................6
6. IANA Considerations .............................................6
7. Acknowledgements ................................................6
8. References ......................................................7
8.1. Normative References .......................................7
8.2. Informative References .....................................7
1. Introduction ....................................................3
1.1. Motivation .................................................3
2. Specification of Requirements ...................................3
3. Rejected Potential Solution .....................................4
4. Solution ........................................................4
4.1. Node Attribute TLV .........................................4
4.2. Operation ..................................................5
5. Security Considerations .........................................6
6. IANA Considerations .............................................6
7. Acknowledgements ................................................6
8. References ......................................................7
8.1. Normative References .......................................7
8.2. Informative References .....................................7
In some cases, it is desirable to set up constrained shortest path first (CSPF) computed Multiprotocol Label Switching (MPLS) Traffic Engineered Label Switched Paths (TE LSPs) to local addresses of a router that are not currently advertised in the TE LSAs, i.e., loopback and non-TE interface addresses.
在某些情况下，需要设置约束最短路径优先（CSPF）计算的多协议标签交换（MPLS）流量工程标签交换路径（TE LSP）到当前未在TE LSA中公布的路由器的本地地址，即环回和非TE接口地址。
For instance, in a network carrying VPN and non-VPN traffic, it is often desirable to use different MPLS TE LSPs for the VPN traffic and the non-VPN traffic. In this case, one loopback address may be used as the BGP next-hop for VPN traffic while another may be used as the BGP next-hop for non-VPN traffic. It is also possible that different BGP sessions are used for VPN and non-VPN services. Hence, two separate MPLS TE LSPs are desirable -- one to each loopback address.
例如，在承载VPN和非VPN流量的网络中，通常希望对VPN流量和非VPN流量使用不同的MPLS TE lsp。在这种情况下，一个环回地址可用作VPN流量的BGP下一跳，而另一个环回地址可用作非VPN流量的BGP下一跳。也可能不同的BGP会话用于VPN和非VPN服务。因此，需要两个独立的MPLS TE LSP——每个环回地址一个。
However, current routers in an OSPF network can only use CSPF to compute MPLS TE LSPs to the router ID or the local addresses of a remote router's TE-enabled links. This restriction arises because OSPF TE extensions [RFC3630, RFC5329] only advertise the router ID and the local addresses of TE-enabled links of a given router. Other routers in the network can populate their traffic engineering database (TED) with these local addresses belonging to the advertising router. However, they cannot populate the TED with the advertising router's other local addresses, i.e., loopback and non-TE interface addresses. OSPFv2 stub links in the router LSA [RFC2328] provide stub reachability information to the router but are not sufficient to learn all the local addresses of a router. In particular for a subnetted point-to-point (P2P) interface the stub, link ID is the subnet address. While for a non-subnetted interface, the stub link ID is the neighbor address. Intra-prefix LSAs in OSPFv3 [RFC5340] are also not sufficient to learn the local addresses.
然而，OSPF网络中的当前路由器只能使用CSPF计算MPLS TE LSP到路由器ID或远程路由器启用TE的链路的本地地址。出现这种限制是因为OSPF TE扩展[RFC3630，RFC5329]仅公布路由器ID和给定路由器的TE启用链路的本地地址。网络中的其他路由器可以使用这些属于广告路由器的本地地址填充其流量工程数据库（TED）。但是，它们不能用广告路由器的其他本地地址（即环回和非TE接口地址）填充TED。路由器LSA[RFC2328]中的OSPFv2存根链路向路由器提供存根可达性信息，但不足以了解路由器的所有本地地址。特别是对于子网点对点（P2P）接口存根，链路ID是子网地址。而对于非子网接口，存根链路ID是邻居地址。OSPFv3[RFC5340]中的内部前缀LSA也不足以学习本地地址。
For the above reasons, this document defines an enhancement to OSPF TE extensions to advertise the local addresses of a node.
出于上述原因，本文定义了对OSPF TE扩展的增强，以公布节点的本地地址。
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 [RFC2119].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照[RFC2119]中所述进行解释。
A potential solution would be to advertise a TE link TLV for each local address, possibly with a new link type. However, this is inefficient since the only meaningful information is the address. Furthermore, this would require implementations to process these TE link TLVs differently from others; for example, the TE metric is normally considered a mandatory sub-TLV, but would have no meaning for a local address.
一个潜在的解决方案是为每个本地地址公布TE链路TLV，可能使用新的链路类型。但是，这是低效的，因为唯一有意义的信息是地址。此外，这将要求实现以不同于其他方式处理这些TE-link TLV；例如，TE度量通常被视为强制性子TLV，但对本地地址没有意义。
The solution is to advertise the local addresses of a router in a new OSPF TE LSA Node Attribute TLV. It is anticipated that the Node Attribute TLV will also prove more generally useful.
解决方案是在新的OSPF TE LSA节点属性TLV中公布路由器的本地地址。可以预期，节点属性TLV也将被证明更普遍地有用。
The Node Attribute TLV carries the attributes associated with a router. The TLV type is 5 and the length is variable. It contains one or more sub-TLVs. This document defines the following sub-TLVs:
节点属性TLV携带与路由器关联的属性。TLV类型为5，长度可变。它包含一个或多个子TLV。本文件定义了以下子TLV：
1. Node IPv4 Local Address sub-TLV 2. Node IPv6 Local Address sub-TLV
1. 节点IPv4本地地址子TLV 2。节点IPv6本地地址子TLV
The Node IPv4 Local Address sub-TLV has a type of 1 and contains one or more local IPv4 addresses. It has the following format:
节点IPv4本地地址子TLV的类型为1，包含一个或多个本地IPv4地址。其格式如下：
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 1 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prefix Len 1 | IPv4 Prefix 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Prefix 1 cont. | :
+-+-+-+-+-+-+-+-+ ~
: . :
~ . +-+-+-+-+-+-+-+-+
: . | Prefix Len n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Prefix n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 1 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prefix Len 1 | IPv4 Prefix 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Prefix 1 cont. | :
+-+-+-+-+-+-+-+-+ ~
: . :
~ . +-+-+-+-+-+-+-+-+
: . | Prefix Len n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Prefix n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Each local IPv4 address is encoded as a <Prefix Length, Prefix> tuple. Prefix Length is encoded in 1 byte. It is the number of bits in the Address and can be at most 32. Prefix is an IPv4 address prefix and is encoded in 4 bytes with zero bits as necessary.
每个本地IPv4地址都编码为<Prefix Length，Prefix>元组。前缀长度以1字节编码。它是地址中的位数，最多可以是32位。前缀是IPv4地址前缀，按4字节编码，必要时为零位。
The Node IPv4 Local Address sub-TLV length is in octets. It is the sum of the lengths of all n IPv4 Address encodings in the sub-TLV, where n is the number of local addresses included in the sub-TLV.
节点IPv4本地地址子TLV长度以八位字节为单位。它是子TLV中所有n个IPv4地址编码的长度之和，其中n是子TLV中包含的本地地址数。
The Node IPv6 Local Address sub-TLV has a type of 2 and contains one or more local IPv6 addresses. It has the following format:
节点IPv6本地地址子TLV的类型为2，包含一个或多个本地IPv6地址。其格式如下：
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 2 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prefix Len 1 | Prefix 1 Opt. | IPv6 Prefix 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Prefix 1 cont. :
: . ~
~ .
: .
: +-+-+-+-+-++-+-+-+-+-++-+-+-+-+-+
: | Prefix Len n | Prefix n Opt. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Prefix n :
| :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 2 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prefix Len 1 | Prefix 1 Opt. | IPv6 Prefix 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Prefix 1 cont. :
: . ~
~ .
: .
: +-+-+-+-+-++-+-+-+-+-++-+-+-+-+-+
: | Prefix Len n | Prefix n Opt. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Prefix n :
| :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--
Each local IPv6 address is encoded using the procedures in [RFC5340]. Each IPv6 address MUST be represented by a combination of three fields: PrefixLength, PrefixOptions, and Address Prefix. PrefixLength is the length in bits of the prefix and is an 8-bit field. PrefixOptions is an 8-bit field describing various capabilities associated with the prefix [RFC5340]. Address Prefix is an encoding of the prefix itself as an even multiple of 32-bit words, padding with zero bits as necessary. This encoding consumes (PrefixLength + 31) / 32) 32-bit words.
使用[RFC5340]中的程序对每个本地IPv6地址进行编码。每个IPv6地址必须由三个字段的组合表示：PrefixLength、PrefixOptions和address Prefix。PrefixLength是前缀的位长度，是一个8位字段。PrefixOptions是一个8位字段，描述与前缀[RFC5340]相关的各种功能。地址前缀是将前缀本身编码为32位字的偶数倍，根据需要填充零位。这种编码消耗（前缀长度+31）/32）32位字。
The Node IPv6 Local Address sub-TLV length is in octets. It is the sum of the lengths of all n IPv6 Address encodings in the sub-TLV, where n is the number of local addresses included in the sub-TLV.
节点IPv6本地地址子TLV长度以八位字节为单位。它是子TLV中所有n个IPv6地址编码长度的总和，其中n是子TLV中包含的本地地址数。
A router announces one or more local addresses in the Node Attribute TLV. The local addresses that can be learned from TE LSAs, i.e., router address and TE interface addresses SHOULD NOT be advertised in the node local address sub-TLV. The local addresses advertised will depend on the local configuration of the advertising router. The default behavior MAY be to advertise all the loopback interface addresses.
路由器在节点属性TLV中宣布一个或多个本地地址。可从TE LSA学习的本地地址，即路由器地址和TE接口地址，不应在节点本地地址子TLV中公布。播发的本地地址将取决于播发路由器的本地配置。默认行为可能是公布所有环回接口地址。
The Node Attribute TLV MUST NOT appear in more than one TE LSA originated by a router. Furthermore, such an LSA MUST NOT include more than one Node Attribute TLV. A Node Attribute TLV MUST NOT carry more than one Node IPv4 Local Address sub-TLV. A Node Attribute TLV MUST NOT carry more than one Node IPv6 Local Address sub-TLV.
节点属性TLV不得出现在路由器发起的多个TE LSA中。此外，这样的LSA不能包含多个节点属性TLV。节点属性TLV不能携带多个节点IPv4本地地址子TLV。节点属性TLV不能携带多个节点IPv6本地地址子TLV。
This document does not introduce any further security issues other than those discussed in [RFC3630] and [RFC5329].
除[RFC3630]和[RFC5329]中讨论的安全问题外，本文件不介绍任何其他安全问题。
IANA has assigned the Node Attribute TLV (value 5) type from the range 3-32767 as specified in [RFC3630], from the top level types in TE LSAs registry maintained by IANA at http://www.iana.org.
IANA已按照[RFC3630]中的规定，从IANA维护的TE LSAs注册表中的顶级类型中，分配范围为3-32767的节点属性TLV（值5）类型http://www.iana.org.
IANA has created and now maintains the registry for the sub-TLVs of the Node Attribute TLV. Value 1 is reserved for Node IPv4 Local Address sub-TLV and value 2 for Node IPv6 Local Address sub-TLV.
IANA已经为节点属性TLV的子TLV创建并维护了注册表。值1为节点IPv4本地地址子TLV保留，值2为节点IPv6本地地址子TLV保留。
The guidelines for the assignment of types for sub-TLVs of the Node Attribute TLV are as follows:
节点属性TLV的子TLV的类型分配准则如下：
o Types in the range 3-32767 are to be assigned via Standards Action.
o 3-32767范围内的类型将通过标准行动进行分配。
o Types in the range 32768-32777 are for experimental use; these will not be registered with IANA, and MUST NOT be mentioned by RFCs.
o 32768-32777范围内的类型用于实验用途；这些将不会在IANA注册，RFC不得提及。
o Types in the range 32778-65535 are not to be assigned at this time. Before any assignments can be made in this range, there MUST be a Standards Track RFC that specifies IANA Considerations that covers the range being assigned.
o 此时不分配32778-65535范围内的类型。在此范围内进行任何分配之前，必须有一个标准跟踪RFC，指定涵盖所分配范围的IANA注意事项。
We would like to thank Nischal Sheth for his contribution to this work. We would also like to thank Jean Philippe Vasseur, Acee Lindem, Venkata Naidu, Dimitri Papadimitriou, and Adrian Farrel for their comments.
我们要感谢Nischal Sheth对这项工作的贡献。我们还要感谢让·菲利普·瓦修尔、亚齐·林登、文卡塔·奈杜、迪米特里·帕帕迪米特里欧和阿德里安·法雷尔的评论。
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.
[RFC2328]Moy，J.，“OSPF版本2”，STD 54，RFC 2328，1998年4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。
[RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering (TE) Extensions to OSPF Version 2", RFC 3630, September 2003.
[RFC3630]Katz，D.，Kompella，K.，和D.Yeung，“OSPF版本2的交通工程（TE）扩展”，RFC 3630，2003年9月。
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF for IPv6", RFC 5340, July 2008.
[RFC5340]Coltun，R.，Ferguson，D.，Moy，J.，和A.Lindem，“IPv6的OSPF”，RFC 53402008年7月。
[RFC5329] Ishiguro, K., Manral, V., Davey, A., and A. Lindem, Ed., "Traffic Engineering Extensions to OSPF Version 3", RFC 5329, September 2008.
[RFC5329]Ishiguro，K.，Manral，V.，Davey，A.，和A.Lindem，Ed.，“OSPF版本3的流量工程扩展”，RFC 53292008年9月。
Authors' Addresses
作者地址
Rahul Aggarwal Juniper Networks 1194 North Mathilda Ave. Sunnyvale, CA 94089
Rahul Aggarwal Juniper Networks加利福尼亚州桑尼维尔北马蒂尔达大道1194号，邮编94089
Phone: +1-408-936-2720
EMail: rahul@juniper.net
Phone: +1-408-936-2720
EMail: rahul@juniper.net
Kireeti Kompella Juniper Networks 1194 North Mathilda Ave. Sunnyvale, CA 94089
Kireeti Kompella Juniper Networks加利福尼亚州桑尼维尔北马蒂尔达大道1194号，邮编94089
EMail: kireeti@juniper.net
EMail: kireeti@juniper.net