Abstract: A method for providing presence gateway functionality includes deriving presence information for subscribers in a first set of subscribers based on telecommunications signaling messages. The first set of subscribers includes at least one subscriber who is not a subscribed-to presentity. The method also includes determining whether presence status information for a subscriber in the first set of subscribers has changed. In response to detecting a change in presence status, it is determined whether the subscriber is a subscribed-to presentity. If the subscriber is a subscribed-to presentity, a presence server is notified of the change in status of the subscriber.

Abstract: Methods and system for delivering presence information regarding push-to-talk subscribers are disclosed. In one method, a short message gateway receives presence information from a first push-to-talk subscriber from a presence or push-to-talk server. The short message gateway determines the location and availability of a second push-to-talk subscriber to which the presence information is directed. If the second push-to-talk subscriber is available, the SMS gateway delivers the presence information to the second push-to-talk subscriber in a manner that bypasses the SMSC. If the SMS gateway determines that the second push-to-talk subscriber is not available, the SMS gateway discards the presence information.

Abstract: A signal transfer point-like network routing element capable of providing call signaling services required in a mobile communications network is disclosed. A mobile services routing node can be configured to provide the functionality of a Home Location Register (HLR), a Visitor Location Register (VLR), an Equipment Identification Register (EIR), and an Authentication Center (AuC). As such, the mobile services routing node is adapted to receive mobile service related signaling messages, perform the necessary mobile service processing, and route response messages as required.