IP Storage: Coming Attraction
IP networking is so widespread that network operators are eager to use it for storage, too. The technology is familiar to many engineers, so labor costs associated with it are lower than the more specialized Fibre Channel storage networking used by most businesses today. Plus, businesses could simplify a bit by running just one type of network, instead of one for general networking and one for storage.
"People can leverage this mature infrastructure that IP's got out there," says Paul Ross, EMC's director of network storage marketing. "Ethernet's been around a long time, therefore it's a commodity, so it's cost effective. Users wouldn't need all these specialized types of equipment, so they'd get cheaper management costs and equipment costs."
In addition, a single Fibre Channel link supports transmission over no more than 10 km, while IP networks travel much farther. Because of its ubiquity, though, expect Fibre Channel to coexist with IP storage for some years to come.
At the moment, IP storage proponents are at work on three different protocols. The most popular seems to be iSCSI, which also has the catchiest name (pronounced "eye-scuzzy"). Whereas Fibre Channel storage technology runs data encapsulated in the SCSI (small computer system interface) standard over Fibre Channel lines, iSCSI runs SCSI inside TCP/IP, typically over an Ethernet network. Vendors including McData, Adaptec, Agilent and IBM recently tested iSCSI products at the University of New Hampshire Interoperability Laboratory.
But because so many businesses use Fibre Channel and will likely continue to do so for some time to come-if only because the technology gets the job done and is already paid for-storage vendors aim to provide IP storage products that let customers continue to use their Fibre Channel technology. So, the IP storage protocols FCIP (Fibre Channel over IP) and iFCP (Internet Fibre Channel Protocol) support the use of both IP storage and Fibre Channel storage in tandem.
FCIP simply runs Fibre Channel over IP so that, among other things, businesses can connect remote storage area networks over an optical IP MAN or WAN. "FCIP enables real-world solutions for companies seeking to expand their storage network infrastructures over longer distances, while protecting their investments in Fibre Channel SANs and IP-based WANs," says Marc Oswald, chairman of the Storage Networking Industry Association's IP Storage Forum FCIP Group.
Meanwhile, iFCP aims to use IP not just to connect SANs, but to interconnect the various Fibre Channel devices that make up SANs, from host bus adapters to hubs to switches and more.
Because businesses are demanding flexible storage solutions that not only help them move onto IP storage but also capitalize on their investment in Fibre Channel, many of today's storage players are covering their bets by working on multiple products, particularly those based on either the iSCSI or FCIP protocols.
EMC's Ross says the race between IP storage networking and Fibre Channel is a bit like the old videocassette player wars between VHS and Betamax. Ultimately, the better, cheaper, faster product wins. But because both technologies continue to develop, the eventual winner might end up being both. -Ted McKenna
telecommagazine.com |
