SS7

A set of telephony signalling protocols which are used to set up the vast majority of the world's PSTN telephone calls. SS7 provides a universal structure for telephony network signalling, messaging, interfacing, and network maintainence. It deals with establishment of a call, exchanging user information, call routing, different billing structures, and supports Intelligent network (IN) services. (Also CCS7(Common Channel Signaling System 7), C7 (CCITT number 7))

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