Domain-Wide Prefix Distribution with Two-Level IS-IS
RFC 5302

Approval announcement
Draft of message to be sent after approval:

From: The IESG <iesg-secretary@ietf.org>
To: IETF-Announce <ietf-announce@ietf.org>
Cc: Internet Architecture Board <iab@iab.org>,
    RFC Editor <rfc-editor@rfc-editor.org>, 
    isis mailing list <isis-wg@ietf.org>, 
    isis chair <isis-chairs@tools.ietf.org>
Subject: Protocol Action: 'Domain-wide Prefix Distribution with 
         Two-Level IS-IS' to Proposed Standard 

The IESG has approved the following document:

- 'Domain-wide Prefix Distribution with Two-Level IS-IS '
   <draft-ietf-isis-rfc2966bis-04.txt> as a Proposed Standard

This document is the product of the IS-IS for IP Internets Working Group. 

The IESG contact persons are Ross Callon and David Ward.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-isis-rfc2966bis-04.txt

Technical Summary

   This document describes extensions to the Intermediate System to
   Intermediate System (IS-IS) protocol to support optimal routing
   within a two-level domain.  The IS-IS protocol is specified in ISO
   10589, with extensions for supporting IPv4 (Internet Protocol)
   specified in RFC 1195.  This document replaces RFC 2966. This
   document extends the semantics presented in RFC 1195 so that a
   routing domain running with both level 1 and level 2 Intermediate
   Systems (IS) [routers] can distribute IP prefixes between level 1 
   and level 2 and vice versa. 

Working Group Summary

   This is part of a series of seven IS-IS RFCs that were originally
   published as informational for historic reasons, but that are now 
   being updated to proposed standard. There is broad consensus in the
   WG for this change. 

Document Quality

   This document has been widely reviewed, and is implemented and
   deployed. 

Personnel

   Chris Hopps and Dave Ward have jointly worked as document shepherds 
   for this bunch of seven documents. Ross Callon is the responsible AD.

RFC Editor Note

   Please replace section 6 (Security Considerations) as follows:

   OLD

     6.  Security Considerations

     This document raises no new security issues for IS-IS.

   NEW

     6. Security Considerations

     This document raises no new security issues for IS-IS; for 
     general security considerations for IS-IS see [RFC3567bis].

   Please add the following informative reference in section 8.2:

     [RFC3567bis]  Li, T. and R. Atkinson, "Intermediate System to
     Intermediate System (IS-IS) Cryptographic Authentication",
     work in progress.
  
   Also please note that this last reference is within a few days
   of being approved, and it probably would be preferable to hold
   this document until you can publish both at the same time.

   Please update all references to [RFC3784] with references to 
   [draft-ietf-isis-te-bis]. If I counted right, this includes five
   references in the regular text, plus the entry for 3784 in the 
   informative references section. Please note that 
   draft-ietf-isis-te-bis is within a few days of being approved, 
   and it probably would be preferable to hold this document until
   you can publish both (and actually all seven IS-IS documents
   being progressed) at the same time. 

   In section 2, third paragraph, second sentence:

   OLD
     However, to prevent routing-loops, L1L2 routers must not
     advertise L2->L1 inter-area routes that they learn via L1 
     routing, back into L2.

   NEW
     However, to prevent routing-loops, L1L2 routers MUST NOT
     advertise L2->L1 inter-area routes that they learn via L1 
     routing, back into L2.

   In section 4, third paragraph, first sentence:

   OLD
   Implementations that follow RFC 1195 should ignore bit 8 in the
   default metric field when computing routes.  

   NEW
   Implementations that follow RFC 1195 SHOULD ignore bit 8 in the
   default metric field when computing routes.