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Nope, it's not. Can you name a phone prefix routing protocol?

Ehm, SS7 ;).

One of the functions provided for in the SS7 network is called Global Title Translation (GTT). The SCCP, in this case call it the switch, has the ability to perform minimal routing using GTT. GTT frees the STP, let's call that the "edge router" from being burdended with lcoations for all possible end nodes. You could say it's like ASN information. It enables the ss7 to pass on small messages that the STP's understand and are able to route on to the next destination in the path until it reaches the final STP and returns an answer in the same fashion. It's a combination of dynamic and static information used to find destinations. [ Long discussion on GTT fundamentals avoided - I recommend "SS7 Signalling - 2nd Edition" for more information on GTT et. al. ] A good example of the integration of SS7 into *IP* routing is to be found in the convergence of SS7 stacks into dial gear which enables the IP network to signal the SS7 network and perform optimized call aggregation. What I mean by this is that instead of dedicating a box of 672 ports to one customer, many customers can share one box and bypass the SCCP (TDM switching component) and talk directly to the PSTN. The aggregation model is much finer in this respect and the utilization of hardware is more cost effective. Kinda old stuff actually circa 1998. So. Yes. Sort of. SS7 is a routing protocol for all intents and purposes. NotSoOb: Verisign runs one of the largest facilities based SS7 networks in the world. -M<