The SS7-ization of the Internet

L eave it to the little guys to do what's important in the market.

Little-known competitive local exchange carrier XCOM Technologies, Inc., which humorously dubs itself "the data phone company," has come up with a way to bypass heavily burdened central office switches when data traffic is involved.

XCOM's first client, Ascend, is probably one of many that is going to start using the smarts of the voice network to figure out what the heck to do with all the data traffic that is blowing through the central office.

The XCOM platform separates data from normal voice traffic using features and intelligence in the public switched telephone network (PSTN), such as Signaling System 7 (SS7) and proprietary software developed by XCOM. Acting like a traffic cop, XCOM's box identifies and directs incoming data straight to a terminal server, bypassing the voice switch entirely.

The result? Data is off-loaded from the congested PSTN, enabling better connectivity and true integration of data and voice traffic.

What will make hot technologies such as virtual private networks hum, and bring IP telephony folk into the mainstream, is the interface of the IP layers with the smarts of existing SS7 databases, to do the things that make sense to all of us.

Recall that it is SS7 and centralized databases that allow you to do geographic and time-based routing of phone calls. If your New York office were closed, then all calls would be routed to your California office, which would still be open. The same would be true of IP-based telephony calls. The need for similar routing is clearly there.

When MCI launched its Vault capability last year, if you squinted at the architecture schematics, you could see dotted lines from the IP switching layer to the SS7 data access points in the MCI architecture.

This was really the first public play for serious integration of data networking with voice networking because it was being done on more than just a transport layer.

As you see telcos such as GTE preparing to do battle with extensive nationwide IP networks, a critical piece has to be SS7 integration.

Still, achieving SS7 and data network integration won't be a trivial task. For example, data networks, and the Internet in particular, handle calls in fundamentally different ways. There are a lot of neat features that carriers have developed over time, such as routing by area code, that will be tough to carry over to the data environment.

But then there are features that reside in the data network that should work easily in an SS7-data network environment. For example, look-ahead routing, which scouts forward in the network for congestion and busy signals, should work well. After all, SS7 is a packet network that talks to all the switches and other network adjunct devices.

Daniel Briere is president and Christine Heckart is vice president of TeleChoice, a consultancy in Boston. They can be reached at dbriere@telechoice.com and checkart@telechoice.com.