methods for providing a circuit switched service for user equipment, on a mobile switching center server, on a mobility management entity, devices on a mobility management entity, on a mobile switching center server, and, system for providing a circuit switched service for user equipment a method and apparatus for providing both circuit switched services (cs) terminated at mobile communication terminals, mt, and originating at mobile communication terminals, mo, such such as short message service, sms, network services using cs fallback and csolte-1 architectures. an extended sgs interface referred to as sgs + (63) is implemented between a mobility entity management, mme, (64) on a core network (11) and a mobile terminal switching center server, msc-s, ( 61). the sgs + interface supports transmission of top layer cs packet data units while using signaling connection control, sccp, or, connectionless or connection oriented operation. the signaling support of the layer without access, nas, between the user user equipment, eu, (27) and the mme (64) is extended to provide support for both mt sms and hand sms services.