I have configured the SIP trunk [unauthenticated] to my services provider for outbound calling.
I can make a call using the SIP trunk configured in callmanager, but call is getting disconnect after every 15 min. Our service provider says every 15 min there there SIP server sends UPDATE messege to call manger which call manager is not responding and that's why call is getting disconnects.
When i checkd 'debug sh ip nat sip' output CM is sending 401 unauthorised message in response to UPDATE message. I am here with attaching the debug output for your referece.
I will be really glad full if someone can provide me the workaround for the same.