A SAN is a dedicated, high-performance network used to move data between servers and storage resources. Because it is a separate, dedicated network, it avoids any traffic conflict between clients and servers.

SAN technology allows high-speed server-to-storage, storage-to-storage, or server-to-server connectivity. This method uses a separate network infrastructure that relieves any problems associated with existing network connectivity.

SANs offer the following features:

• Performance – SANs enable concurrent access of disk or tape arrays by two or more servers at high speeds, providing enhanced system performance.
• Availability – SANs have disaster tolerance built in, because data can be mirrored using a SAN up to 10 kilometers (km) or 6.2 miles away.
• Scalability – Like a LAN/WAN, it can use a variety of technologies. This allows easy relocation of backup data, operations, file migration, and data replication between systems.

Web Links The Lowdown on SAN http://www.gcn.com/21_16/guide/ 19055-1.html