WAFS vs WAN Optimization: No Contest

Two seemingly distinct approaches to remote site data delivery may be moving closer together. Though suppliers deny it, products that support wide-area file services (WAFS) are starting to have a lot in common with so-called WAN accelerators.

Remote sites raise issues for storage managers. Are users getting data fast enough? Are WAN links too costly? Can recovery be performed within SLA timeframes? Is storage underused or overused? Is the headquarters losing control?

One answer is WAFS, comprising software that delivers files in a LAN-like fashion over WANs, through the use of proprietary programs alongside standard file transfer protocols like CIFS and NFS. WAFS vendors include Cisco Systems Inc. (Nasdaq: CSCO), through its $82 million purchase of Actona last year; DiskSites Inc.; FineGround Networks; Riverbed Technology Inc.; and Tacit Networks Inc. (see Cisco Acts on Actona).

WAN accelerators aren't file-oriented but use network-based compression, caching, and other techniques to eliminate repetitive features of WAN traffic, enabling data to travel faster to remote sites (see WAN Accelerators Speed Up and WANs Shape Up for Storage). Vendors include Network Executive Software Inc. (NetEx), Peribit Networks Inc., and Swan Labs Corp.

In theory, these approaches are architecturally different, and suppliers encourage that perception. Each has its pros and cons, but recent evidence shows they have similar features, too.Peribit, for instance, has added so-called application-specific acceleration to its WAN optimizers (see Peribit Intros App Acceleration ). The enhancements cut down repetitive signaling in specific applications, to speed up Microsoft Exchange, CIFS file transfer, and HTTP data over WANs.

Swan Labs has also added application acceleration, via its purchase of Pivia last year (see Swan Labs Picks Up Pivia). Swan Labs offers the software as an add-on to its network appliances, and CEO Andrew Foss says it now accounts for one third of the company's revenue (see Andrew Foss, CEO, Swan Labs Corp.).

Now, consider WAFS vendor Tacit. Though Tacit's had a Windows products since the second quarter of 2004, it has now officially partnered with Microsoft Corp. (Nasdaq: MSFT) to offer not just faster file access but what spokespeople call a "distribution point" for remote-site traffic. Tacit speeds up not only file transfers but DNS, DHCP, software updates, and printing. Email is set to be added this quarter, the vendor says.

In the case of both the WAN optimizers and WAFS gear cited above, the goal is the same, to improve remote site data delivery. Both also use application- or protocol-specific algorithms to get the job done.

But Tacit, for instance, says WAFS is a more reliable approach than WAN optimization. "Okay, they make a few protocols run faster," says CEO Greg Grodhaus. But he hints that scrunching network protocols alone can leave packets missing. The decision between WAFS and WAN optimization is usually made by different IT divisions, he says. WAFS is for storage managers who must have "one hundred percent availability, realiability, and security of mission critical data," he maintains.Peribit, in contrast, says WAFS solutions can threaten data integrity by allowing remote-site copies that can be updated separately from a headquarters file. "With our solution, IT has total centralized control," says Michelle McLean, director of product marketing at Peribit.

It seems that for now, the two camps are bent on keeping their distance. The reasons may have as much to do with marketing as anything else. As customers demand help with remote sites, suppliers want to step up with something new and different. Who wants to be one of the crowd when there's money to be made?

But the next few months will see users delving into vendor claims, and perhaps even demanding that WAFS and WAN optimizers start combining. It may not even be a stretch to think of companies partnering or merging. After all, the move to sell "solutions" instead of point products has worked like a charm for other storage networking companies. Perhaps it can work here, too.

Mary Jander, Site Editor, Byte and Switch