The Future of Ethernet
Cost and complexity were two of the reasons Franklin W. Olin College of Engineering in Needham, Mass., opted to deploy iSCSI-based storage arrays instead of a Fibre Channel-based SAN. With a fully converged IP network in place, sticking with IP-based storage also made sense from an integration standpoint. Not only did the college save money on equipment -- Fibre Channel-based SANs would have cost twice the $100,000 the school spent on two EqualLogic Inc. iSCSI-based SANs -- but it also avoided Fibre Channel consulting fees, says CIO Joanne Kossuth.
"With iSCSI, we get a greater number of servers on the storage array for less cost. The arrays are also easy to set up -- my network administrator can manage them -- and I didn't have to hire a storage manager. There were no two-week consulting fees," says Kossuth.
Although the college's network doesn't currently support 10 Gigabit Ethernet, with Category 6 copper cable inside buildings and fiber between them, the wiring infrastructure is in place to support it.
Indeed, iSCSI storage vendors use continuous Ethernet throughput upgrades as a key selling point. "One piece about Ethernet is it's interoperable and provides an incremental upgrade path, as Gigabit Ethernet moves from the core of the network and then into the data center and then into storage at the edge of the data center. 10 Gigabit Ethernet will expand throughout the network, starting in the core and moving outward," says Eric Schott, director of product management at EqualLogic in Nashua, N.H.
He adds that although prices are dropping rapidly, 10 Gigabit Ethernet prices have a ways to go before they'll rival those of today's 100MB products.
However, as the 10 Gigabit Ethernet spec gets further refined, IT managers will be inclined to look at iSCSI as a viable alternative to Fibre Channel.
"People have been worried about lack of throughput, but now, even people who are still spending money on Fibre Channel might look at iSCSI," says Kossuth. This move will be cost-driven. People who wouldn't want to replace transactional systems with a Fibre Channel array might consider iSCSI as an intermediate step for, say, human resources personnel file storage. As Ethernet bandwidth continues to increase, not only will small and midsize businesses that haven't invested in Fibre Channel benefit; large enterprises might look at copper cabling for departmental storage, says Stephanie Balaouras, an analyst at Forrester Research Inc.