Storage Area Networks (SANs) are growing rapidly because they solve a problem. That problem is the manageability of large and ever increasing amounts of disk storage. When storage is directly attached to the computer using it through a high-speed cable, the storage device can meet the needs of that computer very well. When computers are networked together, each computer with its own attached storage, total storage resource management is difficult or impossible to achieve. The SAN approach offers many storage management advantages, including the ability to: share a pool of storage; easily grow the size of the storage pool; balance the load to each physical device; eliminate downtime; easily share backup devices; backup without degrading performance for the network users; manage your storage resource easily and efficiently; manage your computing resource separately from your storage resource.