Patent ID: 7778215

Claim:
A roaming method for a digital trunked communication network, comprising: originating, by a roaming subscriber, a dispatch call request; conducting, by a visited dispatching subsystem serving the roaming subscriber, routing according to subscriber identification code information of the roaming subscriber; sending, by the visited dispatching subsystem, an authentication request to a home dispatching subsystem of the roaming subscriber; authenticating, by the home dispatching subsystem, the roaming subscriber; forwarding, by the visited dispatching subsystem, the dispatch call request to the home dispatching subsystem; originating, by the home dispatching subsystem, a trunked connection request to one or more subscribers to be involved in the dispatch call; receiving, by the home dispatching subsystem, a call establishment completion notification upon the dispatch call being established; and sending, by the home dispatching subsystem, a dispatch call authorization to the one or more subscribers.