How many times have you heard some e-commerce evangelist say, The Internet changes everything? Now with i-SCSI, the up-and-coming TCP/IP-based storage protocol, the Internet may finally be changing the world of networked storage. Using TCP/IP, i-SCSI encapsulates block-level SCSI data traffic and transports that traffic over any TCP/IP network including, of course, the Internet. Since i-SCSI works with the existing Ethernet infrastructure, it gives storage networking all the benefits of Ethernet networking, such as easy to maintain and easy to control cost of ownership.
Where will i-SCSI make the greatest dent? It will work well enough for organizations large enough to pool their storage and to have Ethernet networking expertise. On the other hand, these organizations are not big enough to have the budget and the IT expertise to manage fibre channel storage area networks (SANs). For such organizations, IP-based SANs using familiar SCSI and Gigabit Ethernet technology open a whole new world of storage networking. Likewise, i-SCSI offers system integrators a chance to solve their customers storage management problems while replacing revenue lost to the dwindling market for direct-attached storage.
Right now only a few i-SCSI appliance-type storage boxes exist on the market exist today. These vendors include IBM and 3Ware. Industry watcher stay that it is still early in the game to be coming out with a product. Later this year when Adaptec and Intel begin to offer host bus adapters with built-in TCP/IP stacks, i-SCSI could get a nice elevator ride to some staying power.
The most likely application for i-SCSI includes pooled storage for application and database servers, which take advantage of i-SCSIs block-level I/O. Using an i-SCSI box, organizations can begin to lower their overall storage costs by consolidating storage for applications, such as Exchange Servers that need to see raw disk. NAS and i-SCSI storage appliances could work together on the front end for an overall SAN-based storage architecture. Whether its NAS or i-SCSI, the concept of the single-use storage appliance can prove valid. i-SCSI boxes, then, can provide some of the same benefits as NAS appliances, such as easy to install and to maintain and a low cost of ownership.
Looking at the big picture, i-SCSI can be used to create dedicated, Ethernet-based SANs and to network among existing fibre channel SANs. i-SCSI storage routers from Cisco and Nishan Systems, for example, allow organizations to use existing Internet infrastructure at the core to connect SANs together, and for storage replication. Applications like these make i-SCSI worth watching. For mid-size organizations, NAS combined with i-SCSI could be the storage networking technology they have been dreaming about.