Goals for IPv6 Site-Multihoming Architectures (RFC3582)
Original Publication Date: 2003-Aug-01
Included in the Prior Art Database: 2003-Aug-20
Internet Society Requests For Comment (RFCs)
J. Abley: AUTHOR [+3]
This document outlines a set of goals for proposed new IPv6 site- multihoming architectures. It is recognised that this set of goals is ambitious and that some goals may conflict with others. The solution or solutions adopted may only be able to satisfy some of the goals presented here.
Network Working Group J. Abley
Request for Comments: 3582 ISC
Category: Informational B. Black
AOL Time Warner
Goals for IPv6 Site-Multihoming Architectures
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright (C) The Internet Society (2003). All Rights Reserved.
This document outlines a set of goals for proposed new IPv6 site-
multihoming architectures. It is recognised that this set of goals
is ambitious and that some goals may conflict with others. The
solution or solutions adopted may only be able to satisfy some of the
goals presented here.
Site-multihoming, i.e., connecting to more than one IP service
provider, is an essential component of service for many sites which
are part of the Internet.
Current IPv4 site-multihoming practices have been added on to the
CIDR architecture , which assumes that routing table entries can
be aggregated based upon a hierarchy of customers and service
However, it appears that this hierarchy is being supplanted by a
dense mesh of interconnections . Additionally, there has been an
enormous growth in the number of multihomed sites. For purposes of
redundancy and load-sharing, the multihomed address blocks are
introduced into the global table even if they are covered by a
provider aggregate. This contributes to the rapidly-increasing size
of both the global routing table and the turbulence exhibited within
it, and places stress on the inter-provider routing system.
Abley, et al. Informational [Page 1]
RFC 3582 IPv6 Site-Multihoming Goals August 2003
Continued growth of both the Internet and the practice of site-
multihoming will seriously exacerbate this stress. The site-
multihoming architecture for IPv6 should allow the routing system to
scale more pleasantly.
A "site" is an entity autonomously operating a network using IP, and
in particular, determining the addressing plan and routing policy for
that network. This definition is intended to be equivalent to
"enterprise" as defined in .
A "transit provider" operates a site that directly provides
connectivity to the Internet to one or more external sites. The
connectivity provided extends beyond the transit provider's own site.
A transit provider's site is directly connected to the sites for
which it provides transit.
A "multihomed" site is one with more than one transit provider.
"Site-multihoming" is the practice of arranging a site to be
The term "re-homing" denotes a transition of a site between two
states of connectedness due to a change in the connectivity between
the site and its transit providers' sites.
3. Multihoming Goals
3.1. Capabilities of IPv4 Multihoming
The following capabilities of current IPv4 multihoming practices
should be supported by an IPv6 multihoming architecture.