[rfc-dist] RFC 5549 on Advertising IPv4 Network Layer Reachability Information with an IPv6 Next Hop

rfc-editor@rfc-editor.org rfc-editor at rfc-editor.org
Mon May 4 16:46:57 PDT 2009

A new Request for Comments is now available in online RFC libraries.

        RFC 5549

        Title:      Advertising IPv4 Network Layer Reachability 
                    Information with an IPv6 Next Hop 
        Author:     F. Le Faucheur, E. Rosen
        Status:     Standards Track
        Date:       May 2009
        Mailbox:    flefauch at cisco.com, 
                    erosen at cisco.com
        Pages:      10
        Characters: 23637
        Updates/Obsoletes/SeeAlso:   None

        I-D Tag:    draft-ietf-softwire-v4nlri-v6nh-02.txt

        URL:        http://www.rfc-editor.org/rfc/rfc5549.txt

Multiprotocol BGP (MP-BGP) specifies that the set of network-layer
protocols to which the address carried in the Next Hop field may
belong is determined by the Address Family Identifier (AFI) and the
Subsequent Address Family Identifier (SAFI).  The current AFI/SAFI
definitions for the IPv4 address family only have provisions for
advertising a Next Hop address that belongs to the IPv4 protocol when
advertising IPv4 Network Layer Reachability Information (NLRI) or
VPN-IPv4 NLRI.  This document specifies the extensions necessary to
allow advertising IPv4 NLRI or VPN-IPv4 NLRI with a Next Hop address
that belongs to the IPv6 protocol.  This comprises an extension of
the AFI/SAFI definitions to allow the address of the Next Hop for
IPv4 NLRI or VPN-IPv4 NLRI to also belong to the IPv6 protocol, the
encoding of the Next Hop in order to determine which of the protocols
the address actually belongs to, and a new BGP Capability allowing
MP-BGP Peers to dynamically discover whether they can exchange IPv4
NLRI and VPN-IPv4 NLRI with an IPv6 Next Hop.  [STANDARDS TRACK]

This document is a product of the Softwires Working Group of the IETF.

This is now a Proposed Standard Protocol.

STANDARDS TRACK: This document specifies an Internet standards track
protocol for the Internet community,and requests discussion and suggestions
for improvements.  Please refer to the current edition of the Internet
Official Protocol Standards (STD 1) for the standardization state and
status of this protocol.  Distribution of this memo is unlimited.

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