SBC CNe SIP Options Ping

The SBC CNe application supports the SIP OPTIONS ping feature. A SIP OPTIONS request is periodically sent to a pre-configured or FQDN IP peer (IPv4 and IPv6 are supported) to check its connectivity status. The OPTIONS request is sent via the Signaling Port of the zone configured for the peer. If InActivityMonitoringTimer is set to a non-zero value and the PathCheck profile is enabled for an IP Peer, then the OPTIONS ping health check will pause for a time-interval equal to InActivityMonitoringTimer when there is SIP traffic from the IP Peer. The OPTIONS ping resumes after the configured InActivityMonitoringTimer timeout is counted from the endpoint's last SIP msg.

The configurable ping mechanism verifies peer-to-peer connectivity between the SBC and Endpoint Peer. The Path Check Profile feature supports this ping mechanism with SIP OPTIONS. Configure this feature using an IPv4/IPv6 address. If a signaling failure is detected, the SIP signaling microservice in the SBC CNe cluster rejects all signaling packets destined for the associated signaling peer. The Path Check Profile specifies the conditions constituting a connectivity failure and the recovery procedures. The existing profile parameters, Send Interval, Reply Timeout Count, and Recovery Count, detect failure conditions and initiate the recovery procedures.

With this feature:

• The OPTIONS PING monitoring starts for an (IP PEER) endpoint if the Path Check Profile is provisioned.
• The SBC sends a SIP OPTIONS ping and receives 200 OK for SIP OPTIONS messages.
• The SBC CNF cluster uses an interval configured in the new parameter InActivityMonitoringTimer introduced under the Path Check Profile to monitor the IP Peer activity. If there is no SIP message activity for the "InActivityMonitoringTimer" duration,  the OPTIONS ping message is sent to the IP PEER to prevent the OPTION ping message from being paused for the above duration.
• The SBC considers an IP PEER (endpoint) active if it receives SIP messages from that endpoint. 
• The SBC stops the OPTION PING monitoring for active (IP PEER) endpoints with SIP message call flows.
• The SBC resumes the OPTION ping monitoring for endpoints after the configured InActivityMonitoringTimer timeout from the last received SIP msg from the endpoint expires.

The configurable InActivityMonitoringTimer interval timer parameter stops an endpoint's OPTION ping when the SIP traffic is active. If the timer is set to 0, then the OPTION ping won't be paused for that Path Check Profile attached to the IP Peers. 

When the InActivityMonitoringTimer interval is set to a non-zero value, the SBC CNe checks the activity status after the expiry of the time interval period. If an endpoint peer attached to the Path Check Profile is active, then the OPTION ping pauses for that interval period.

The time interval range for this parameter is 0-600 secs. The recommended value of the InActivityMonitoringTimer is  4 or 5 times the SendInterval value.