SIP 503 Service Unavailable is commonly seen in a VoIP network when a SIP device (such as a SIP server) is knowingly unable to process a call. Typically when this happens the endpoint that originated the Invite will try the next available host it receives in the SIP Contact header. In this particular example lets [...]
Archive for March, 2011
Broadsoft and Cisco SIP 503 “Retry-After” SIP Header Support
Posted: 23rd March 2011 by Mark in BroadWorks, Cisco, SIP2