Method and apparatus for managing subscriptions for a subscription-notification service

A method for managing a presence service comprising:

• receiving, at a Subscription Service Host server, a plurality of subscription requests associated with a plurality of subscribers, wherein each subscription request of the plurality of subscription requests comprises a request to subscribe to presence information of a status publication source;
• in response to receiving the plurality of subscription requests, creating a corresponding subscription to presence information for each subscriber of the plurality of subscribers;
• monitoring, by the Subscription Service Host server, a system condition;
• determining, by the Subscription Service Host Server and based on the monitored system condition indicating a system congestion condition, to at least temporarily suspend, but not delete, a particular subscription to presence information of a particular subscriber of the plurality of subscribers until the system congestion condition is relieved, and responsively;
• determining, by the Subscription Service Host Server, a priority associated with each subscriber of the plurality of subscribers;
• determining, by the Subscription Service Host Server, to suspend the particular subscription to presence information of the articular subscriber based on the priority associated with the particular subscriber being lower than a priority of another subscriber of the plurality of subscribers whose subscription is not suspended;
• placing, by the Subscription Service Host server, the particular subscription to presence information into a suspended state to produce a suspended subscription to presence information, wherein the Subscription Service Host Server suspends the particular subscription to presence information without receiving, from the particular subscriber, a request to suspend the particular subscription to presence information and without deleting the particular subscription to presence information;
• and subsequent to placing the particular subscription to presence information into the suspended state, determining, by the Subscription Service Host server, to one of reactivate and terminate the suspended particular subscription to presence information.