Internet Engineering Task Force (IETF) G. Tsirtsis
Request for Comments: 6626 V. Park
Updates: 5177 V. Narayanan
Category: Standards Track Qualcomm
ISSN: 2070-1721 K. Leung
Cisco
May 2012
Internet Engineering Task Force (IETF) G. Tsirtsis
Request for Comments: 6626 V. Park
Updates: 5177 V. Narayanan
Category: Standards Track Qualcomm
ISSN: 2070-1721 K. Leung
Cisco
May 2012
Dynamic Prefix Allocation for Network Mobility for Mobile IPv4 (NEMOv4)
移动IPv4（NEMOv4）网络移动性的动态前缀分配
Abstract
摘要
The base Network Mobility for Mobile IPv4 (NEMOv4) specification defines extensions to Mobile IPv4 for mobile networks. This specification defines a dynamic prefix allocation mechanism for NEMOv4.
移动IPv4的基本网络移动性（NEMOv4）规范定义了移动网络对移动IPv4的扩展。本规范定义了NEMOv4的动态前缀分配机制。
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/rfc6626.
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/rfc6626.
Copyright Notice
版权公告
Copyright (c) 2012 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2012 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 ...........................................2
3. Dynamic Mobile Prefix Allocation ................................2
3.1. Mobile Client Considerations ...............................2
3.2. Home Agent Considerations ..................................3
4. Security Considerations .........................................4
5. IANA Considerations .............................................4
6. Acknowledgements ................................................4
7. Normative References ............................................4
1. Introduction ....................................................2
2. Requirements Notation ...........................................2
3. Dynamic Mobile Prefix Allocation ................................2
3.1. Mobile Client Considerations ...............................2
3.2. Home Agent Considerations ..................................3
4. Security Considerations .........................................4
5. IANA Considerations .............................................4
6. Acknowledgements ................................................4
7. Normative References ............................................4
The base NEMOv4 specification [RFC5177] defines extensions to Mobile IPv4 [RFC5944] for mobile networks. This specification adds support for dynamic allocation of mobile prefixes by the home agent.
基本NEMOv4规范[RFC5177]定义了移动网络对移动IPv4[RFC5944]的扩展。此规范增加了对归属代理动态分配移动前缀的支持。
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。
The following extension is defined according to this specification.
以下扩展是根据本规范定义的。
According to this specification, the Prefix field of the Mobile Network Request extension MUST be set to zero to indicate that the Mobile Router requests mobile network prefix(es) be assigned to it by the home agent. In this case, the Mobile Router MAY set the prefix length field of such extensions to zero or to a length of its choice as a hint to the home agent. According to this specification, Mobile Network Request extensions with the Prefix field set to zero MAY be included in a registration request message either during initial registration or during a subsequent registration.
根据该规范，移动网络请求扩展的前缀字段必须设置为零，以指示移动路由器请求归属代理向其分配移动网络前缀。在这种情况下，作为对归属代理的提示，移动路由器可以将这种扩展的前缀长度字段设置为零或其选择的长度。根据该规范，前缀字段设置为零的移动网络请求扩展可以在初始注册期间或在后续注册期间包括在注册请求消息中。
When a Mobile Router receives a registration reply, it MUST process it as defined in Mobile IPv4 [RFC5944] and [RFC5177]. If one or more network acknowledgement extensions are included with the Code field set to "Success", the Mobile Router SHOULD treat the prefixes in the corresponding Prefix fields as allocated prefixes and create the appropriate bindings as defined in [RFC5177].
当移动路由器收到注册回复时，它必须按照移动IPv4[RFC5944]和[RFC5177]中的定义对其进行处理。如果代码字段设置为“成功”时包含一个或多个网络确认扩展，则移动路由器应将相应前缀字段中的前缀视为已分配的前缀，并创建[RFC5177]中定义的适当绑定。
In response to a registration request with a Mobile Network Request extension with the Prefix field set to zero, if a Mobile Router receives a registration reply with a network acknowledgement extension including Code field set to 1 "invalid prefix", it may use it as a hint that the home agent does not support dynamic prefix allocation.
响应于具有前缀字段设置为零的移动网络请求扩展的注册请求，如果移动路由器接收到具有包括代码字段设置为1“无效前缀”的网络确认扩展的注册应答，则其可以将其用作归属代理不支持动态前缀分配的提示。
A home agent receiving a Mobile Network Request extension with the Prefix field set to zero MAY return a Mobile Network Acknowledgement extension [RFC5177] with the Prefix field set to the prefix allocated to the Mobile Router. The length of that prefix is at the discretion of the home agent. The home agent MAY take into account the prefix length hint if one is included in the Mobile Network Request extension. Once the home agent allocates a prefix, it MUST maintain the prefix registration table as defined in [RFC5177]. Alternatively, the home agent MAY return a Mobile Network Acknowledgement extension with the Code field set to one of the negative codes defined in [RFC5177].
接收到前缀字段设置为零的移动网络请求扩展的归属代理可以返回前缀字段设置为分配给移动路由器的前缀的移动网络确认扩展[RFC5177]。该前缀的长度由国内代理自行决定。如果在移动网络请求扩展中包括前缀长度提示，则归属代理可以考虑前缀长度提示。归属代理分配前缀后，必须维护[RFC5177]中定义的前缀注册表。或者，归属代理可以返回移动网络确认扩展，其中代码字段设置为[RFC5177]中定义的否定代码之一。
Dynamic mobile prefix allocation, as defined in this specification, MAY be combined with dynamic home address allocation, as defined in [RFC5177]. In other words, the home address field of the registration request message MAY be set to zero while the message also includes one or more Mobile Network Request extensions with the Prefix field also set to zero.
本规范中定义的动态移动前缀分配可与[RFC5177]中定义的动态家庭地址分配相结合。换句话说，注册请求消息的归属地址字段可以设置为零，而消息还包括一个或多个前缀字段也设置为零的移动网络请求扩展。
Once the home agent allocates a prefix, it MUST maintain the prefix registration table as defined in [RFC5177]. The lifetime of the allocated prefix will be equal to the lifetime of the binding cache entry. The Mobile Router may request for multiple mobile network prefixes to be assigned by the home agent. For a Mobile Network Prefix for which the assignment was unsuccessful, the Code field in the corresponding Mobile Network Acknowledgement extension should be set to 4 (MOBNET_UNASSIGNED).
归属代理分配前缀后，必须维护[RFC5177]中定义的前缀注册表。分配的前缀的生存期将等于绑定缓存项的生存期。移动路由器可以请求由归属代理分配多个移动网络前缀。对于分配不成功的移动网络前缀，相应移动网络确认扩展中的代码字段应设置为4（MOBNET_UNASSIGNED）。
For dynamic prefix allocation, the Mobile Router's home address MAY be used to identify the client if it is not set to zero. Otherwise, as defined in the Network Access Identifier (NAI) extension [RFC2794] of Mobile IPv4 [RFC2794], the NAI extension needs to be included in the registration request, in which case the same extension SHOULD be used to identify the Mobile Router for prefix allocation purposes.
对于动态前缀分配，如果未设置为零，则可使用移动路由器的家庭地址来识别客户端。否则，如移动IPv4[RFC2794]的网络访问标识符（NAI）扩展[RFC2794]中所定义，需要在注册请求中包括NAI扩展，在这种情况下，应使用相同的扩展来识别移动路由器以用于前缀分配。
This specification operates in the security constraints and requirements of Mobile IPv4 [RFC5944], NAI [RFC2794], and [RFC5177].
本规范在移动IPv4[RFC5944]、NAI[RFC2794]和[RFC5177]的安全约束和要求下运行。
Home agent implementations SHOULD take steps to prevent address exhaustion attacks. One way to limit the effectiveness of such an attack is to limit the number and size of prefixes any one Mobile Router can be allocated.
归属代理实现应采取措施防止地址耗尽攻击。限制此类攻击有效性的一种方法是限制任何一个移动路由器可以分配的前缀的数量和大小。
A new value has been assigned in the Mobile Network Acknowledgement Extension registry: 4 - Home Agent cannot assign a mobile network prefix (MOBNET_UNASSIGNED).
移动网络确认扩展注册表中分配了一个新值：4-归属代理无法分配移动网络前缀（MOBNET_UNASSIGNED）。
The authors would like to thank Pete McCann, Alexandru Petrescu, Ralph Droms, and Jari Arkko for their reviews and comments.
作者要感谢皮特·麦肯、亚历山大·彼得雷斯库、拉尔夫·德罗姆斯和贾里·阿克科的评论和评论。
[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。
[RFC2794] Calhoun, P. and C. Perkins, "Mobile IP Network Access Identifier Extension for IPv4", RFC 2794, March 2000.
[RFC2794]Calhoun，P.和C.Perkins，“IPv4移动IP网络访问标识符扩展”，RFC 27942000年3月。
[RFC5177] Leung, K., Dommety, G., Narayanan, V., and A. Petrescu, "Network Mobility (NEMO) Extensions for Mobile IPv4", RFC 5177, April 2008.
[RFC5177]Leung，K.，Dommety，G.，Narayanan，V.，和A.Petrescu，“移动IPv4的网络移动（NEMO）扩展”，RFC 5177，2008年4月。
[RFC5944] Perkins, C., "IP Mobility Support for IPv4, Revised", RFC 5944, November 2010.
[RFC5944]Perkins，C.，“IPv4的IP移动支持，修订版”，RFC 59442010年11月。
Authors' Addresses
作者地址
George Tsirtsis Qualcomm
George Tsirtsis高通公司
EMail: tsirtsis@googlemail.com
EMail: tsirtsis@googlemail.com
Vincent Park Qualcomm
文森特公园高通公司
Phone: +908-443-8141
EMail: vpark@qualcomm.com
Phone: +908-443-8141
EMail: vpark@qualcomm.com
Vidya Narayana Qualcomm
维迪亚·纳拉亚纳高通公司
Phone: +858-845-2483
EMail: vidyan@qualcomm.com
Phone: +858-845-2483
EMail: vidyan@qualcomm.com
Kent Leung Cisco
梁建邦
Phone: +408-526-5030
EMail: kleung@cisco.com
Phone: +408-526-5030
EMail: kleung@cisco.com