Abstract: The apparatus, method and system embodiments of the present invention provide for maintaining call control at a gateway mobile switching center (MSC), for roaming mobile units, utilizing a packet network or link, such as an ATM link. The preferred system embodiment includes a gateway MSC, a serving MSC, and a base station having a wireless link with the roaming mobile unit. The gateway MSC includes a protocol handler for voice (PHV).

Abstract: A cellular system in accordance with the principles of the present invention permits one node, or network element, within a cellular system to request dialed number validation from another network element in the cellular system. The invoking and responding nodes may be any of the following: a mobile switching center, a home location register, a service control point, or a service node. Upon reaching a state in call processing where further dialed number analysis may be required, the invoking node will send an ANSI-41 compliant dialed number validation request message to the node performing validation. The validating node will determine whether the dialed number is allowed under the subscriber's dialing plan. After making the determination, the validating node will return a message to the invoking node indicating whether the specified digits are allowed according to the subscriber's dialing plan.