SIP Options Polling can be used to determine the status of a remote endpoint, helping reduce post dial delay from Apeiron to a particular destination address if an IP becomes unresponsive. If a device/IP is declared down from an Apeiron SIP IP that device/IP will be skipped during routing done by the Apeiron SIP IP.
Options Polling is enabled per Trunk Group ID (TID) within the Trunk Configuration page. The poll will start after a call is made to a particular FQDN/IP within a Trunk Group; every IP within the trunk will be polled from each of active Apeiron's SIP IPs and any non-responsive souce & destination IP address combination will be removed from service until proper poll responses are restored.
Apeiron's SIP IPs will always respond to customer SIP IPs programmed on an active account. There is no configuration parameter to be set.
Apeiron standard requirements call for a 200OK response from customer endpoints for SIP Options to operate properly. If you need to reply with something other than 200OK then please open a ticket so we can determine the best way to accommodate your config.
Apeiron default configurations call for SIP Options to be enabled if more than one customer IP address is active on the trunk group, or if the customer trunk group is configured for off-net DR or overflow forwarding.
The default SIP OPTIONS process is:
The ping period is 60 seconds. OPTIONS are sent to all the IPs listed within a trunk group by each of Apeiron's SIP IPs configured on the trunk group.
If there is no response, OPTIONS are resent every 5 seconds.
After 6 resends and no response, the IP is declared down and it is skipped during routing, until the 60 sec poll is answered.
If no calls are made for more than 30 minutes, the polling is disabled until traffic resumes.