Hello experts,
I am running normal SIP Phones 7945 and 7965 on CUCM 8.6. I am trying to use a SBC (SIP based) to do the registration in SRST mode. This SIP SBC is cable of accepting REGISTER request. When the WAN link goes down the IP Phone sends register request to SIP SBC. And register without any issue. It can also register back to CUCM when WAN link is back online.
Issue: when WAN link fails and when Phones goes in SRST mode, the Username used is CUCM generated. e.g. 12347291847-qwed123-123123....@<Phone IP>
Instead of Ext. On CUCM i had applied digest username and password. still does not use the ext as username.
How can use Ext as Contact SIP header. Is there any configuration on CUCM?
thanks
