Network Basics: Differences between SAN and NAS

It’s easy to confuse the terms storage area network (SAN) and network attached storage (NAS). Both refer to relatively new network technologies that let you manage the disk storage on your network.

However, NAS is a much simpler and less expensive technology. A NAS device is nothing more than an inexpensive self-contained file server. Using NAS devices actually simplifies the task of adding storage to a network because the NAS eliminates the chore of configuring a network operating system for routine file-sharing tasks.

A storage area network is designed for managing very large amounts of network storage — sometimes downright huge amounts.

A SAN consists of three components: storage devices (perhaps hundreds of them), a separate high-speed network (usually fiber-optic) that directly connects the storage devices to each other, and one or more SAN servers that connect the SAN to the local area network. The SAN server manages the storage devices attached to the SAN and allows users of the LAN to access the storage.

Setting up and managing a storage area network is a job for a SAN expert. For more information about storage area networks, see the home page of the Storage Networking Industry Association at www.snia.org.