B Timer
The B Timer is the maximum amount of time that the Orchestrator will wait for a provisional response to a SIP Invite message (i.e. a SIP 18x response). An extension of PDD, B-Timer moves a call to the next trunk or trunk group if no provisional response is received from the vendor. The portal activates B-Timer when the INVITE Invite sent to the outgoing trunk does not receive a 100 Trying within the allocated time. If the allocated time exceeds the portal limit, the call rolls over to the next Trunk or Trunk Group if available.
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Set PDD to 10 seconds and B Timer to 5 3 seconds.