Subject: Protocol Action: 'IPv4 routes with an IPv6 next hop in the Babel routing protocol' to Proposed Standard (draft-ietf-babel-v4viav6-08.txt)

From: The IESG <[email-masked]>
Date: Tue, 01 Mar 2022 15:06:20 -0800

The IESG has approved the following document:
- 'IPv4 routes with an IPv6 next hop in the Babel routing protocol'
  (draft-ietf-babel-v4viav6-08.txt) as Proposed Standard

This document is the product of the Babel routing protocol Working Group.

The IESG contact persons are Alvaro Retana, John Scudder and Martin Vigoureux.

A URL of this Internet Draft is:
https://datatracker.ietf.org/doc/draft-ietf-babel-v4viav6/

Technical Summary

   This document update the Babel routing protocol to support
   announcing routes to an IPv4 prefix with an IPv6 next-hop. This
   makes it possible for IPv4 traffic to flow through interfaces that
   have not been assigned an IPv4 address. Since an IPv6 next hop can
   use an IPv6 link-local address that is autonomously configured, the
   use of such routes enables a mode of operation where the network
   core has no statically assigned IP addresses.

Working Group Summary

   The Babel WG was enthusiastic about this update to the Babel
   protocol. Things were moving along when the group hit the speed
   bump of what IPv4 source address to use when a v4-via-v6 Babel
   router generates a v4 ICMP message. It took a little while to
   resolve that resulting in the current specification which includes
   use of the IPv4 dummy address if no other source of an IPv4 address
   is available on the router. Based on the mailing list and WG
   meetings, there is strong consensus for the draft.

Document Quality

   This a reasonably short document of high quality. v4-via-v6 has
   been implemented in babeld but not merged into the mainline source
   yet. It has not yet been implemented in BIRD but the maintainer
   has indicated their intention to do so. (The use of the IPv4 dummy
   address when generating a v4 packet with no v4 addresses configured
   has been submitted for inclusion in the Linux kernel.)

Personnel

  Document Shepherd: Donald Eastlake
  Area Director: Martin Vigoureux