Abstract: Switchable nodes (300), such as satellites (20,21) and/or gateways (40,41), along with a modified call setup procedure are used in satellite communication system (100) to prevent fraudulent users from misusing resources by not allowing those resources to be available until the call setup procedure is completed. Also, both satellites and gateways monitor traffic to determine when unauthorized traffic is occurring. Switchable nodes (300) can intercept calls for both monitoring and control purposes and deny access to fraudulent and suspicious users and communication units.

Abstract: Originating and terminating units (32, 36) communicate through a network (22) containing satellites (46, 50, 52) and gateways (44, 48). The network (22) receives user-prioritized lists (62) of protocols from the respective units (32, 36). The network (22) compares the lists (62) to determine the highest-priority common protocol. If a common protocol exists, the network (22) establishes a link between the units (32, 36) utilizing the common protocol and excluding the gateways (44, 48). If a common protocol does not exist, the network (22) selects as originating and terminating protocols the highest-priority protocols in the respective lists (62). If the originating protocol consumes a greater number of resources, the network (22) establishes the link, translating between protocols in an originating gateway (44) and excluding a terminating gateway (48). Otherwise, the network (22) establishes the link, translating in the terminating gateway (48) and excluding the originating gateway (44).

Abstract: Methods (100, 150, 200) and systems (10, 30, 41) are used to expedite access for a period of time for those subscriber units (30) which have previously executed the complete visited gateway access procedures. By checking certain information sent by a subscriber unit (30) upon initialization and determining whether the information falls within a predetermined period of time, the visited gateway (41) enables itself to receive calls directly from the subscriber unit (30) and informs the subscriber unit (30) that it (30) can send calls directly to the visited gateway (41). The subscriber unit (30) thereafter sends calls to the visited gateway (41) instead of to the home gateway (40) until it (30) is no longer allowed to do so.

Abstract: A system (10) and method (100) selects one of the gateways (40, 41) to set-up and maintain signalling resources associated with a call. Instead of having two gateways (40, 41) handle signalling resources, a single gateway (40) becomes the serving gateway for one or both of the subscriber units' call segment. The system and method do not establish a transit connection between gateways (40, 41).

Abstract: A method (100) and system (10) are used to expedite access for a period of time for those subscriber units (30) which have previously executed the complete home gateway access procedures. By checking certain information sent by a subscriber unit (30) upon initialization and determining whether the information falls within a predetermined period of time, a home gateway (40) directly notifies a visited gateway (41) to handle the call setup and bypasses the need to reexecute the full access procedures at the home gateway (40).

Abstract: A system (10) and method (100) reduce an amount of signalling resources used for calls involving more than one gateway (40, 41). Instead of having two gateways (40, 41) handle signalling resources, one gateway (40) becomes the serving gateway for a subscriber unit call segment. For signalling cut-through, a call is set-up in the usual way with a transit connection established between gateways (40, 41). After normal call set-up completed, including voice cut-through, signalling cut through is invoked to remove the need to maintain the transit connection and one local connection for the duration of the call. The old local connection is replaced with a new local connection to the serving gateway.

Abstract: Methods (100) assign a subscriber unit (30) to be served by a gateway (40) based on such factors as the location of the subscriber unit (30), whether the call is to be intercepted and whether the serving gateway (40) is capable of servicing the connection request. The method (100) does not drop a call because the visited gateway initially assigned by the home gateway (40) is unable to service the connection request; but instead routes the call around disabled or congested gateways to an alternate visited gateway that is capable of servicing the connection request.

Abstract: A subscriber unit (26) contains location data that expires after predetermined time periods that are based on the subscriber's mobility. When the location data has not expired, the subscriber unit requests access (108) to a satellite communication system (10) by providing location data within an access request message. The communication system performs a quick check (214) to validate the location data. Accordingly, time-consuming geo-location procedures are avoided when a call is initiated or being received. When the location data has expired, the subscriber unit requests access (110) without providing location data within the access request message. The communication system performs a complete geolocation procedure (210) to determine valid location data for the subscriber unit. The location data is sent (211) to the subscriber unit and time stamped (113).