EMC, for one, recently signed two WAN accelerator vendors to its network-attached storage (NAS) Partner Program: Riverbed Technology, San Francisco, CA, and its Steelhead appliances; and Peribit, Santa Clara, CA, with its Sequence Reducer (SR-100) and Sequence Mirror (SM-500) products. IBM, meanwhile, is now a reseller of Tacit Networks' Ishared platform, which performs file caching and LAN protocol optimization.

WAN accelerators--or optimization appliances--use a lot of tricks to speed up data transmissions. These include compression, file caching and optimization of protocols such as CIFS or HTTP, making it feasible to maintain files in a central repository without incurring the wrath of remote workers. John Webster, senior analyst at the Data Mobility Group, has also seen WAN accelerators as makeshift data migration tools, for example, between recently merged companies. "You have data here, and you want it there--there are a lot of solutions that can do that for you."

But the most dramatic impact of a WAN accelerator to storage management is that it makes remote office backup easier and more cost-efficient. "If you're the storage guy responsible for backing up 500 remote offices and you install our appliance, you can take 500 autoloaders out of those 500 offices," saving on hardware, tape media, maintenance and time, says Eric Wolford, Riverbed vice president of marketing and business development. After installing Steelhead at one remote office, a 5GB backup that previously took seven hours over the WAN completed in under 30 minutes, he reports.

It's easy to see the appeal of WAN acceleration appliances for larger storage vendors. "What EMC loves is the fact that with our product installed, all the bytes that were stored at the edge are now stored in the data center," Wolford says.