A method and system for client identification include a control unit configured to enable call service features in communication devices supported by the control unit. A first communication device transmits an off-hook message to the call control unit with a first memory-space physical address locally accessed from memory associated with the first communication device. The first physical address represents a location in main memory of call service profile data associated with the first communication device. The control unit responds to the first physical address by accessing a first data set from the main memory. A verification program determines whether the first data set includes the first call service profile. The control unit enables a first set of call services indicated by the first call service profile data for the first communication device if the first call service profile is included in the first data set. If the first data set does not include the first call service profile data, the control unit searches for a current address of the first call service profile, transmits the current address to the first communication device, and accesses the first call service profile from the current address before enabling the first set of call services. In a preferred embodiment, the first communication device locally stores call service profile addresses for a local communication device and a remotely located communication device. The call control unit is configured to enable call services in the local and remotely located communication devices in response to receiving the call service profile addresses for the local and remotely located communication devices in call-setup messages transmitted by the first communication device.