You can assign default values for the expiration times of PUBLISH and SUBSCRIBE requests by modifying their values in the configuration file.
The expiration time for any PUBLISH or SUBSCRIBE request is determined by the request's Expires header. You can configure Presence Server to assign a default expiration time when a request does not have an Expires header. You can also define a maximum expiration time, used when the value in the Expires header exceeds a certain threshold, and a minimum time, below which requests are rejected.
Expiration times are measured in minutes. To change the settings of expiration times for PUBLISH and SUBSCRIBE requests, complete the following steps: