DPI: The good, the bad, the stuff no one talks about

Part One

Few technologies get their own Congressional hearings, but deep packet inspection is proving to be no ordinary technology. And even if the July 17th House Telecommunications Subcommittee hearing on DPI included the occasional accidental reference to “deep pocket inspection” from elected officials, it was clear that DPI is squarely in the political crosshairs as a potentially dangerous tool for ISPs.

The primary concern raised in Washington is user privacy, foreshadowing the possibility of unprecendented federal rules over how this technology can be used by ISPs.

At the same time, however, vendors are still piling into the DPI arena, promising more and better ways for service providers to manage traffic, use their network resources more efficiently, protect latency-sensitive voice and video signals, and even develop new services that promise new revenues. Variations on the DPI theme include what Ovum Vice President Mark Seery has dubbed “deep session inspection,” a process that goes beyond just looking at packets and includes elements of subscriber management, which edge router vendor Zeugma Systems is deploying.

What drives the DPI forces forward, despite political uncertainty, is the reality that Internet traffic, and particularly IP video traffic, is certain to clog the current ISP infrastructure. At an Internet Innovation Alliance meeting held in May, University of Minnesota Professor Andrew Odlyzko put the issue in simple terms: While Internet traffic is growing at 50% per year, Internet infrastructure, including storage, server farms and transmission facilities, is growing at only 19% per year.

“It’s all being driven from demand for bandwidth,” said Rob Malan, chief technology officer of Arbor Networks, which acquired DPI pioneer Ellacoya. “There is more bandwidth demand than they have capacity available. Service providers have to manage that network somehow to maximize the capacity they do have available. If they don’t manage it, it ends up managing itself, which is a train wreck. So you either increase the capacity to stay ahead of demand, which is too expensive, or you manage the capacity.”

DPI provides tools to address congestion issues and use networks more efficiently, especially as Internet video begins to dominate, said Matt Davis, Yankee Group analyst. That has DPI vendors thinking in a more positive way.

“Some of the thinking is that there is a positive side of this story where consumers don’t feel they are getting the short end but rather telecom service providers can do things with network control and optimization that would benefit the consumer,” Davis said.