Subject: Re: [MBONED] Reporting Issues with NAT

From: "SAYKO, ROBERT J (ATTSI)" <[email-masked]>
Date: Wed, 16 Mar 2011 14:48:30 -0400

At AT&T base on our experience,  testing and investigation we would like
to present the following recommendation as an addition to the
"Automatic IP Multicast Without Explicit Tunnels
(AMT)draft-ietf-mboned-auto-multicast-10" 

Problem:
Reporting Issue:
-It may be useful for GW (or associated app) to record usage log
-It may be useful to correlate those logs with AMT Relay logs
-AMT GW may have no knowledge of the external source IP address and port
as it was perceived by the AMT Relay (due to NAT)

Recommendation:
-The Relay  could inform the AMT GW of the actual source IP address and
port
-Previously, recommendation was made to pass this information back in
the Relay Advertisement message.   However, due to  
 Symmetric NAT, our recommendation is now to pass this information back
in the AMT Query message.
-The information would be tagged on to end of the AMT Query message as
an option.   The presence of the optional data would be signaled in the
Reserved field.

Robert Sayko
AT&T Labs
732-420-3292
[email-masked]