InformationWeek

But that may change soon. More plug-and-play offerings are emerging. Vendors such as Auspex, ECCS, Network Appliance, and Quantum's Snap Server division offer file-serving appliances that easily snap on to an existing IP network. These appliances handle all the files a server would ordinarily process, making information move around faster. They also free up those servers to do everything else more quickly than they could before.

This type of storage is called network-attached storage (NAS), and it evolved as an alternative to storage systems directly connected to each server on a network, called direct-attached storage. Network storage based on Fibre Channel--a gigabit interconnect technology that allows concurrent communications among mainframes, servers, workstations, and data storage systems using SCSI and IP protocols--is called a storage area network. The SAN is fast becoming the de facto enterprise storage framework. Compaq, Dell, EMC, Hewlett-Packard, Hitachi Data Systems, IBM, and Sun Microsystems all compete in this arena.

With a SAN, the Fibre Channel network moves data among pools of servers and storage systems. No server has to be locked into one storage system, and IT executives can set up the architecture based on application requirements.

SANs excel at moving blocks of data quickly and safely; they don't help at all with file management. NAS appliances, on the other hand, exist to do file management, but they're relatively slow when it comes to moving the information. Eventually, says Mark Santora, senior VP of marketing at Network Appliance Inc., the distinction will disappear and both will evolve into storage networking. NAS appliances and SAN components will talk to each other, and software will manage both across the network.