switching subsystem (GSM) (SSS)

The switching subsystem(SSS) implements the entire switching technology with all network transitions in a GSM network. This subsystem is also referred to as the Network Subsystem( NSS).

The switching subsystem manages the radio channels and allocates them to the individual mobile stations. It determines the whereabouts of the mobile station and supports functions related to the mobility of the subscriber. It is also responsible for exchanging signaling information with the various directories, the Home Location Register( HLR) and the Visitor Location Register( VLR) with the mobile switching center( MSC), as well as for encryption and for checking the authenticity of the subscriber.