- standard developed in the late 1970s by the International Telecommunication Union Telecommunication Standardization Sector (ITU-T)
- The SS7 network provides the intelligence to the existing PSTN
•SS7 is used to perform out-of-band
signaling in the Public Switched Telephone Network (PSTN).
•SS7 signaling enhances the PSTN by handling call establishment, exchange of information, routing, operations, billing, and support for Intelligent Network (IN) services.