4/24/2012 -- Time to brush up on your acronyms.

Take DPI, for example. It doesn't just stand for dots-per-inch. And while economists tend to emphasize one kind of DPI -- namely, disposable personal income -- service providers have developed an appetite for still another flavor: deep packet inspection.

In fact, it's one of the hottest growth areas in the service provider networking segment. And you can bet it's a market area that Cisco Systems Inc. and some of its competitors are paying especially close attention to.

According to market watcher Infonetics Research, service providers plunked down almost half a billion dollars for DPI gear in 2011.

That's just chump change, however. By 2016, Infonetics projects, DPI will generate almost $2 billion in annual sales. That's more like it.

Cisco doesn't currently lead the DPI segment -- Infonetics lists rival Huawei as the overall market leader, followed closely by DPI specialist Sandvine -- but it's right in the thick of things. And with all indicators suggesting that service providers plan to boost their consumption of DPI technologies, right in the thick of things isn't a bad place to be. "Though fixed-line operators continue to invest in deep packet inspection solutions for traffic management and to manage the impact of over-the-top ... content on their networks, wireless operators are looking to DPI for more granular traffic management, including prioritization and strategic offload, and are starting to deploy DPI hand-in-hand with their LTE network upgrades," said Shira Levine, a directing analyst at Infonetics Research, in a prepared release.

If anything, Levine understates the case. For one thing, the fortunes of DPI are tightly coupled to the fortunes of high-speed mobile. Now that the market has finally settled on LTE as the 4G standard -- and now that and more consumers are opting for data-hungry smartphones -- DPI seems like a lead-pipe cinch.

But wait, there's more: According to Infonetics, DPI is increasingly being used to support application-specific offerings, including video optimization and mobile-offload. Service providers are experimenting with using it in other scenarios, too. "Operators are evaluating alternatives to throttling or blocking high-bandwidth video content, including using DPI for media caching, to prioritize select video content to support guaranteed QoS and as part of a content delivery network strategy."
-- By Stephen Swoyer