Businesses should expect to face a wide and confusing array of choices when seeking the right WAN-acceleration gear to make transaction times tolerable as they shift from branch office servers to centralized server farms.

Centralization reduces the number of servers and so saves capital and maintenance costs, and improves security. But it also means more end users access data via the WAN - users who will scream if performance degrades as a result.

Availl, Cisco and Brocade offer products tuned to speed up specific types of WAN traffic - wide-area file services or WAFS - which represent a large chunk of the new WAN traffic that results when servers are centralized. But a throng of other vendors says its more broadly focused gear is better suited to real customer needs. All WAN traffic can benefit from acceleration, they say, and not all WAN traffic is WAFS.

This more broadly focused equipment can boost the performance of a range of network traffic, not just WAFS, although some vendors are tuning their gear so it gives special treatment to WAFS, as well. These WAN-acceleration vendors include Array Networks, Converged Access, Expand, Juniper, Orbital Data, Packeteer, Riverbed Technology, Silver Peak Systems, Swan Labs and others.

As an example of this tweaking for WAFS, Packeteer this week is announcing a software download for its PacketShaper appliances that can target priority treatment for Microsoft Windows Server 2003 R2, as well as Active Directory, Exchange and distributed component object model traffic. Packeteer also is teaming with Tacit Networks to provide a separate Tacit appliance that caches data in branch offices as a way to speed WAN transactions.

A crowded field

The WAN acceleration field is crowded because vendors have the opportunity to get a cut of the $5 billion spent this year on branch office infrastructure, and that number will rise next year, says Cindy Borovick, director of data center networks for IDC.

If the devices can help data center consolidation by boosting performance, they can pay for themselves over time, making them attractive to corporations, she says. But the variety of vendors and the varying mix of techniques they use mean customers have to do their homework to find the product that is best for them.