A storage area network (SAN) is a dedicated, independent high-speed network that interconnects and delivers shared pools of storage devices to multiple servers. Each server can access shared storage as if it were a drive directly attached to the server. A SAN is typically assembled with cabling, host bus adapters, and SAN switches attached to storage arrays and servers. Each switch and storage system on the SAN must be interconnected.
A SAN and network attached storage (NAS) are two different types of shared networked storage solutions. While a SAN is a local network composed of multiple devices, NAS is a single storage device that connects to a local area network (LAN).
A SAN switch is hardware that connects servers to shared pools of storage devices. It is dedicated to moving storage traffic in a SAN.