Signaling System No. 7 (SS7) is a common channel signaling (CCS) system developed to satisfy the telephone operating companies' requirements for an improvement to earlier inband signaling systems. The SS7 network consists of three distinct components. A service switching point (SSP) is a telephone switch interconnected by SS7 links. It performs call processing on calls that originate, tandem or terminate at that node. A signal transfer point (STP) is a switch that relays SS7 messages between network switches and databases. A service control point (SCP) contains databases for providing enhanced services.