First-Hop Router Selection by Hosts in a Multi-Prefix Network
RFC 8028
Document | Type |
RFC - Proposed Standard
(November 2016; Errata)
Updates RFC 4861
|
|
---|---|---|---|
Authors | Fred Baker , Brian Carpenter | ||
Last updated | 2020-04-02 | ||
Replaces | draft-baker-6man-multi-homed-host | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Jouni Korhonen | ||
Shepherd write-up | Show (last changed 2016-05-05) | ||
IESG | IESG state | RFC 8028 (Proposed Standard) | |
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Suresh Krishnan | ||
Send notices to | "Jouni Korhonen" <jouni.nospam@gmail.com> | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | No IANA Actions |
Internet Engineering Task Force (IETF) F. Baker Request for Comments: 8028 Updates: 4861 B. Carpenter Category: Standards Track Univ. of Auckland ISSN: 2070-1721 November 2016 First-Hop Router Selection by Hosts in a Multi-Prefix Network Abstract This document describes expected IPv6 host behavior in a scenario that has more than one prefix, each allocated by an upstream network that is assumed to implement BCP 38 ingress filtering, when the host has multiple routers to choose from. It also applies to other scenarios such as the usage of stateful firewalls that effectively act as address-based filters. Host behavior in choosing a first-hop router may interact with source address selection in a given implementation. However, the selection of the source address for a packet is done before the first-hop router for that packet is chosen. Given that the network or host is, or appears to be, multihomed with multiple provider-allocated addresses, that the host has elected to use a source address in a given prefix, and that some but not all neighboring routers are advertising that prefix in their Router Advertisement Prefix Information Options, this document specifies to which router a host should present its transmission. It updates RFC 4861. Status of This Memo This is an Internet Standards Track document. 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. 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/rfc8028. Baker & Carpenter Standards Track [Page 1] RFC 8028 Router Selection in a Multi-Prefix Network November 2016 Copyright Notice Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved. 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. Table of Contents 1. Introduction and Applicability . . . . . . . . . . . . . . . 3 1.1. Host Model . . . . . . . . . . . . . . . . . . . . . . . 4 1.2. Requirements Language . . . . . . . . . . . . . . . . . . 5 2. Sending Context Expected by the Host . . . . . . . . . . . . 5 2.1. Expectations the Host Has of the Network . . . . . . . . 5 2.2. Expectations of Multihomed Networks . . . . . . . . . . . 7 3. Reasonable Expectations of the Host . . . . . . . . . . . . . 7 3.1. Interpreting Router Advertisements . . . . . . . . . . . 7 3.2. Default Router Selection . . . . . . . . . . . . . . . . 9 3.3. Source Address Selection . . . . . . . . . . . . . . . . 9 3.4. Redirects . . . . . . . . . . . . . . . . . . . . . . . . 9 3.5. History . . . . . . . . . . . . . . . . . . . . . . . . . 10 4. Residual Issues . . . . . . . . . . . . . . . . . . . . . . . 10 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 6. Security Considerations . . . . . . . . . . . . . . . . . . . 11 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 7.1. Normative References . . . . . . . . . . . . . . . . . . 11 7.2. Informative References . . . . . . . . . . . . . . . . . 12 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 13 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 Baker & Carpenter Standards Track [Page 2] RFC 8028 Router Selection in a Multi-Prefix Network November 2016 1. Introduction and Applicability This document describes the expected behavior of an IPv6 [RFC2460] host in a network that has more than one prefix, each allocated by an upstream network that is assumed to implement BCP 38 [RFC2827] ingress filtering, and in which the host is presented with a choice of routers. It expects that the network will implement some form of egress routing, so that packets sent to a host outside the localShow full document text