What DPI can do for you

DPI also can enable core network security to ensure things such as BGP updates to routers and overall network upgrades from IPv4 to IPv6 are handled correctly, said Peder Jungck, cofounder and CTO of CloudShield.
“There are many legitimate applications, like four-digit dialing on a VoIP plan,” Jungck said.

Local caching of videos: “We are seeing interest among service providers for video caching of popular content from places like YouTube, when one video is downloaded 1000 times an hour,” Allot’s Cullen said. “You can serve that in a local cache – we announced that capability with PeerApp at NXTcomm – so you don’t use up network capacity delivering all those videos individually.”

Subscriber management: Mark Seery, vice president at Ovum, created the term deep session inspection to describe a process of looking, not at the packet level but at the entire session, whether it’s a VoIP call or a video download or a data transaction. Seery sees DSI playing an important role in delivering more advanced services. “We have gone through a phase on the carrier side where we have boxes that do dense subscriber management but there’s not a lot of traffic per subscriber,” he said. “Then we had boxes that tried to combine lots of traffic with dense subscriber management, and those are only just now maturing.” The next phase is likely to combine subscriber management with high throughput but also the high computational power that DPI/DSI systems require to enable more specialized services per subscriber, he said.

Tiered services: The same people who object to using DPI to differentiate how traffic is treated also object to tiered services on principle, but many within the telecom industry believe that it is inevitable that usage and cost will be linked and that consumers who want more bandwidth or higher quality service will have to pay more. DPI would enable tiered services to be established by making sure all traffic is handled in the appropriate way based on the subscriber’s level of service.

Application-specific services: Today’s networks support a wider range of applications, which must contend for network resources, said Tom Donnelly, co-founder and EVP of DPI technology company Sandvine. “Networks have finite resources, they have finite capacity, but applications are unconstrained in their design. How can they consume that capacity in a way that is fair to everyone?” Sandvine announced what it calls FairShare as an applications-neutral approach to allocating resources based on policies set up by service providers. “You will apply a policy that is QoS-based or shaping-oriented, and service providers will choose a variety of approaches to engineering efficiency in their networks.”

[Note: This is the third installment in a series on DPI. The first two parts can be read here and here.]