[secdir] Secdir review of draft-ietf-mipshop-pfmipv6-09

[Brian Weis <[e-mail]>]

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 adds Proxy-based Fast Handover to Mobile IPv6 (MIPv6).  
It allows fast handover of a mobile device between mobile access  
gateway's without the mobile node itself being involved.

The document primarily reuses messages flows from a previously defined  
handover method (RFC 5568), and Proxy Mobile IPv6 (RFC 5213). It also  
depends on the Security Considerations from RFC 5213 and RFC 5568,  
which seems appropriate given that the same message flows are used  
between the same network entities. These existing RFCs describe IPsec  
ESP as the method for protecting messages, and include details in  
setting up the SPD and PAD. I believe pointing to those documents for  
security consideration guidance is generally acceptable.

There is one new message flow, which is the forwarding of data packet  
from the previous mobile access gateway (PMAG) to the next mobile  
access gateway (NMAG) during transition. The last paragraph in the  
security considerations section notes that these packets MAY be  
encrypted with IPsec "if protection of data traffic is required". A  
better statement might be that they SHOULD be encrypted if the link  
between the PMAG and NMAG exposes the MN packets to more threats than  
if they had followed their normal routed path.

(One miscellaneous comment: It would be helpful to readers if you  
added a definition of "Local Mobility Anchor" to the Terminology  
section.)

Brian

-- 
Brian Weis
Router/Switch Security Group, ARTG, Cisco Systems
Telephone: [phone]
Email: [e-mail]