SIP to SIP transcoding

[David Lin]

I am using 2851 to transcode G.711 to G.729 by SIP. When the SIP call reaches 2851, it responds 100 Trying, then gets "501 Not Implemented" Error and call dropped.

When I tried SIP to H.323 transcoding it works fine. I allowed the SIP to SIP in Voice service. What's should I rectify this problem? Thanks!

allow-connections h323 to h323

allow-connections h323 to sip

allow-connections sip to h323

allow-connections sip to sip

h323

sip

[Tommer Catlin]

Check the IOS level of the router. I have had an issue before with SIP not working correctly either. I think you need to upgrade to the latest and greatest to fix this problem if I recall.

[David Lin]

I'm using c2800nm-adventerprisek9-mz.124-20.T1. I think it's pretty new one.

[Tommer Catlin]

12.4.22T(ED) is the latest.