What is a SAN?

A Storage Area Network (SAN) organises all storage devices by attaching them to a network in a many to many configuration. This improves the bandwidth of all of the storage solutions, and permits all servers to access the devices connected to the SAN.

SANs generally interface via Fibre Channel, a fibre optic cable that provides a web of access via switches and hubs to servers. SANs can also be constructed using SCSI technology.

With many vendors looking to enter this sector, though, there is a range of products on offer, but no standard yet for the SAN solution. As SANs require installation of switch and network infrastructure, they can also be expensive to implement.

Benefits of SAN:

¥ Frees storage load from user network, as data moves over a separate network

¥ Allows all servers to see all storage

¥ Permits simultaneous access from storage libraries

¥ Facilitates centralised management

¥ Fibre Channel SANs allow up to 10km between network points (compared with 25m for SCSI)

¥ Low impact to users during backup operations