iSCSI SAN Storage Server
What is iSCSI? It is the packetization of SCSI commands over internet protocol. This allows a storage system to be seen by your computer as a locally attached SCSI storage device, even if it is physically located at a remote location. In fact, the iSCSI target (the storage) can be located anywhere, on a different floor, in a different building, in a different city, in a different state or even in a different country all you need is internet connectivity. This distance independent characteristic of iSCSI provides tremendous flexibility for management of storage systems. For example, all company data can be centrally located and managed at a secure location. Modern desktop operating systems have iSCSI initiator capabilities (the client side) and modern server operating systems have iSCSI target capabilities (the server side) built in so implementation of iSCSI storage costs very little and requires no specialized network hardware or cabling. The main challenge for iSCSI is maintaining low latency. While the mass storage does not need to be located near your desktop computers, as a practical matter, since the data is going over the internet or your on private ip network, busy networks and slow internet connections will have a negative impact on performance. However, Ethernet network speeds continue to improve, from 10 to 100 and now 1 gigabit (soon 10 gigabit networks will become common place) leading to a shift from the traditional SAN with its dedicated network to the iSCSI SAN which runs SCSI command sets over internet protocol. iSCSI SANs can run over “standard” Ethernet and thus are simpler to manage and less costly to implement. Since they run internet protocol, they can be accessed over the internet, eliminating the cable length limitations of the traditional SAN. As Ethernet speeds increase, the performance benefit of a dedicated SAN network over an iSCSI SAN is diminished. In fact, installations demanding lower latency and or higher throughput can run iSCSI SANs over 10GB Ethernet or Infiniband. It doesn’t require a crystal ball to see that the future of storage area networks largely belongs to iSCSI.