US Patent 7218935 Calls spanning sub-domains with independent call linkage

A communications network, method and computer program product for managing network calls. Calls between mobile stations at base transceiver stations (BTS), each connected to a different base station controller (BSC) in a different switching sub-domain are passed between BSCs over a dedicated line between endpoints. Call linkage for the calls pass in call context objects separate from the calls and need not pass in a signaling channel with the calls.