Incoming call disconnects after 32 seconds!!!

Scenario:

  • Inbound: Optus -> SBC -> ShoreTel
  • Incoming call from Optus to Shoretel drops after 32 seconds

Diagram:

  • Optus -> SBC -> ShoreTel

32-seconds-hangup

As you can see on the SIP ladder diagram above, there’s unusual multiple 200 OK response from ShoreTel.

Solution: Unfortunately, the solution wasn’t shared by ShoreTel engineers, however the fixed was done on their end. So the next time you see above trace within SBC, immediately asks assistance from ShoreTel engineer to address the issue on their end.

Cheers!