Deep packet inspection (DPI) technology has been denounced in the halls of Congress, reviled by consumer protection groups as a means of invading privacy and singled out by net neutrality backers as proof that large Internet service providers are up to no good.

Service providers won’t talk about how -- or even if -- they are using it. The companies that use DPI are even trying to invent new names to describe its function, to avoid labeling their products with this toxic template.

And yet vendors continue to flock to this space – at NXTcomm08, companies such as Procera, Ixia and AdvancedIO all made new product announcements incorporating or related to DPI. The technology also is showing up in new parts of the network; a new edge router from Zeugma Systems uses technology that goes one step beyond DPI to provide many of the same features and benefits, including more sophisticated policy management capabilities. AdvancedIO is focusing much of its efforts on wireless data networks, where bandwidth is more scarce and therefore in greater need of protection.

Enterprise products from the likes of Bivio and F5, which are now moving into the service provider space, allow corporations to control how their bandwidth is used by employees. And the DPI pioneers -- companies such as Ellacoya (now part of Arbor Networks), Sandvine and Allot Communications -- continue to expand the reach and power of their product lines as well. Additional computing power is being added by component companies such as Continuous Computing, which fuels Procera’s solution, to make more detailed packet inspection easier to do without slowing throughput.

There is clearly still significant product development, both ongoing and new, that has DPI at its core. And there are multiple efforts to use DPI in new ways, to enable a range of good things from greater network efficiency to improved security to new revenue-generating services.