Subject: [secdir] SecDir review of draft-ietf-6renum-enterprise-04

From: Yaron Sheffer <[email-masked]>
Date: Fri, 14 Dec 2012 12:34:02 +0200

I have reviewed this document as part of the security directorate's
ongoing effort to review all IETF documents being processed by the IESG.
These comments were written primarily for the benefit of the security
area directors.  Document editors and WG chairs should treat these
comments just like any other last call comments.

This document reviews best practices in renumbering IPv6 enterprise 
networks.

I apologize for my belated review, and hope it is still useful to the 
authors and document reviewers.

Summary

The Security Considerations section appears appropriate for this type of 
document. I do not see any issues that should block the document from 
advancing.

Details

- Usage of FQDN: I don't understand why RFC 5996 (IKEv2) is cited, I 
suspect this is a typo. Otherwise, please clarify.
- The "Security" subsection of 4.1 overlaps with the Security 
Considerations section, and I would recommend to consolidate them.
- 4.1, "Miscellaneous": I accept the recommendation to use FQDNs instead 
of IP addresses. But saying "connections can survive" implies to me that 
live TCP connections will survive an IP renumbering event, which is not 
the case. I would say "connectivity to the remote side can survive" instead.
- 4.3: RFC 2230 is mentioned as a way to deal with naming of IPsec 
endpoints. I am not aware of current implementations of this RFC (in 
fact it is not even mentioned in the current IPsec Roadmap document, RFC 
6071). Moreover, there is community consensus that IPsec should not be 
used in the absence of a key management protocol. And IKE/IKEv2 
certainly supports naming/identifying endpoints by FQDN.
- The Security Considerations are sufficient IMO. The first point (using 
renumbering to escape blacklisting) is appropriate in the context, even 
if per Martin Stiemerling's comment, this strategy may not be very 
effective. This is not a recommendation on how to bypass blacklisting, 
just a description of a potential vulnerability.

Thanks,
      Yaron