For many business users the demand for storage is being stimulated by companies and users coming to the realization that the one thing on their computers they keep, upgrade after upgrade, generation after generation, is their data files.
The rapidly growing demand for storage can affect any enterprise, be it a large company or a small office. Large companies can find great numbers of distinct storage devices expensive and complex to manage, especially when the storage devices are heterogeneous, that is, when they have a wide variety of different storage drives and device types to manage. Small offices can also feel the pinch of rapid storage growth when their storage consumption doubles every year, and they find they lack the information management personnel to modify their network infrastructure and applications to keep up with their expanding number of storage devices.
With the advent of Storage Area Networks (SANs), IT managers finally have a way to aggregate storage resources to a central repository that is not only easier to manage but more scalable and more reliable compared to current distributed storage infrastructures.
A SAN is a special purpose high-speed network that provides direct connections between storage devices (referred to as “targets”) and servers (often referred to as “initiators” in the storage world); though some server OS’s can also act as iSCSI Targets, making their shared storage available to iSCSI Initiators on the network. In yesterday’s marketplace, SANs were almost synonymous with Fibre Channel, a computer, storage, and network device communications protocol designed for high performance information transfer that is capable of high bandwidth (100MB/s, 1GB/s and beyond), flexible topologies, and connectivity over several kilometers.
It is important to remember that a SAN is indeed a network and that, over the course of its evolution, the SANs seen in IT organizations will contain a mix of networking connectivity options, including Fibre Channel, the emerging iSCSI, and the Fibre Channel over IP standards like iFCP. Though the majority of software and hardware for SANs are Fibre Channel based today, we believe the storage networks of tomorrow will contain at least as much iSCSI as fibre channel, and iSCSI may even overtake fibre channel SANs as the iSCSI SAN features equal FC SANs, at a lower price point.