SS7-over-IP signaling transport

SIGTRAN protocols connect IP-based or IP-enabled Media Gateway Controllers (MGCs), Signaling Gateway (SG), switches, databases and other Next Generation signaling applications with traditional circuit-switched signaling architecture.

Figure 2-3 SS7-over-IP Network

In SS7-over-IP networks, traditional SS7 signals from a telephone company switch are transmitted to a Signaling Gateway, which wraps the signals in an IP packet for transmission over IP to either the next Signaling Gateway or to a MGC, other Service Control Points, or Mobile Switching Centers (MSCs). SIGTRAN protocols define how the SS7 messages can be transported reliably over the IP network; see also Role of SIGTRAN.

The Signaling Gateway has a critical role in the integrated network and is often deployed in groups of two or more to ensure high availability. The Signaling Gateway provides transparent interworking of signaling between TDM and IP networks. The Signaling Gateway may terminate SS7 signaling or translate and relay messages over an IP network to a Signaling End Point (SEP) or another Signaling Gateway, which may be separate physical devices or integrated in any combination. For example, the EAGLE can perform the functions of a Signal Transfer Point in addition to those of a Signaling Gateway.