Long time between Trying and OK

I have an Asterisk 18.5.1 system which is taking too much to send 200 back:

  1. At 0.000000 seconds: An INVITE request is sent from SIP-Trunk to Asterisk.
  2. At 0.000071 seconds: A 100 Trying response is sent from Asterisk to SIP-Trunk.
  3. At 18.022963 seconds: A 200 OK (INVITE) response is sent from Asterisk to SIP-Trunk.
  4. At 18.084965 seconds: An ACK request is sent from SIP-Trunk to Asterisk and the call continue properly…

As you see there’s an 18-second delay between the 100 Trying and the 200 OK (INVITE) messages, impacting user experience negatively.

How can I improve this situation? Worth to mention I do not see resource limitations (server’s CPU, memory,…)during call establishment.

Try disabling the STUN server (if applicable).

1 Like

Thanks very much!. Disabling STUN on that interface (SIP Trunk)reduced delay to 9 seconds, Wow! I will check (off hours) if disabling system wide improves even more. Appreciate any other tip.