A storage area network (SAN) is an architecture to attach remote computer storage devices, such as disk arrays, tape libraries  and optical jukeboxes to servers in such a way that the devices appear as locally attached to the operating system. A SAN typically is its own network of storage devices that are generally not accessible through the regular network by regular devices. The cost and complexity of SANs has dropped in recent years, resulting in much wider adoption across both enterprise and small to medium sized business environments