This thesis deals with the major concepts, evolution, and the implementation of common channel signaling systems in current telecommunications networks. An analytical model for performance evaluation of networks design, using Signaling System #7, is presented. The primary emphasis is to calculate the average delay of messages based upon error probability and data transmission rate. The thesis describes existing common channel signaling systems. CCITT Signaling System #6 and #7 are explained. United States versions of signaling systems, CCIS #6 and CCS #7 are examined in detail. The move toward Integrated Services Digital Networks (ISDNs) is discussed in terms of interfaces, and standards. CCS architectures in support of ISDNs are outlined.