Limitations of SIP Agent Reachability

Last Updated : Jul 21, 2015 |

The SIP Agent Reachability feature has the following limitations:

  • SIP Agent Reachability feature is network-intensive and is a CPU.

  • Receives a lower priority than call processing and other competing services on Communication Manager. Therefore the feature can take a longer duration to determine the reachability of the stations in the period as administered in the SIP Reachability Polling Interval and SIP Unreachable Polling Period fields.

  • Starts 15 minutes after the specific Communication Manager is started.

  • Determines the reachability status of a SIP Station by polling the respective Session Manager designated for the SIP station. Communication Manager determines the designated Session Manager by determining the route-pattern. Therefore a trunk-group is required to reach Session Manager.

  • Does not consume any trunk resources.

  • Reachability determination using the SIP OPTIONS message does not interact with Look Ahead Routing (LAR). If OPTIONS polling fails with the primary Session Manager, the polling is retried with the secondary Session Manager(if administered) irrespective of LAR administration.