Busy as beavers before winter, Fibre Channel device manufacturers have been upgrading and replacing their products with new lines, new features and new compatibilities. This industry has been plagued with technical incompatibilities and internal political strife. Only the threat of Ethernet and iSCSI making Fibre Channel obsolete has galvanized vendors. Prices are falling and the products are becoming commoditized.
Fibre Channel switches, the SAN's backbone, sit between storage devices and servers. This market has three sectors that align closely with those of the Ethernet market. At the low end, Fibre Channel hubs are small, shared-media devices that are largely obsolete. At the top of the market, director-class switches are the equivalent of enterprise-class Ethernet switches. Directors have as many as 256 ports, multiple redundant power supplies, multiple redundant data paths and nondisruptive code-load capabilities. In the middle sit the workgroup-class, 2-GB switches, with up to 32 ports in density, 1U or 2U high. These units generally lack the high-availability features found in director-class switches.
For our tests of midrange switches, three vendors sent us products that met our specifications. QLogic Corp.'s SANbox 2 and Brocade Communications Sytems' SilkWorm 3800 have 16 ports each; McData Corp.'s Sphereon 4500 is a 24-port unit.
We also invited Cisco Systems, Gadzoox and Vixel to participate in our tests. But Cisco's switches are currently in beta and therefore didn't qualify. Vixel declined, commenting that our Spirent SmartBits Fibre Channel test equipment is incompatible with its switch. The Spirent equipment worked fine with the other switches, so we wonder what's up with Vixel's switch. Gadzoox, currently under Chapter 11 protection from bankruptcy, claimed a shortage of available people and equipment to support the review, as the company moves its headquarters to a less pricey facility.
Performance testing, a key part of our review because of the importance of the traffic the switches carry, gave us a wild ride. Nervous vendors ushered their switches into Network Computing's Green Bay, Wis., Real-World Labs® like parents taking their children to kindergarten for the first time. We conducted full-mesh testing, in which every port sends frames to every other port; frame-loss testing; and several latency tests, including full-mesh, standard industry latency and our own latency-under-load test. Only the frame-loss tests came out exactly as expected: None of the switches dropped a single frame, even when we accidentally misconfigured a test.
None of these products can be characterized as a bad performer; however, results did vary. QLogic's SANbox 2 showed consistent numbers across the board. But Brocade SilkWorm 3800 gave us some squirrelly test results. At 100 percent load on the full-mesh latency test, for example, the Brocade switch's latency ranged from seven to 85 times that of the second-place competitor. Brocade attributed this anomaly to the SilkWorm 3800's extra buffering algorithms, which threw the results off because our test measures buffer latency only. (Brocade also does not have a single integrated circuit, which the McData and QLogic products have, nor is its buffer RAM integrated on the IC.)
McData's Sphereon 4500 showed some good latency numbers, especially in the full-mesh latency tests. Curiously, that switch also showed the worst numbers in the industry-standard port-to-port tests but very good results in latency-under-load tests and full-mesh latency tests.
Switch interoperability has finally arrived in the Fibre Channel market. After years of reluctance to embrace this practice (a common problem in the storage industry), at least some vendors are giving it a try, as Ethernet and IP have found room to compete in the storage market. McData and Brocade have been among the worst offenders. Brocade owns more than 90 percent of the midrange market, while McData dominates in the high-end director-class switch arena, yet neither has officially supported interoperability between their respective switch brands.
Recently, however, McData got religion. The company has transformed itself into an active force for interoperability--much like QLogic has always been--and is truly trying to make its products work with those of its competitors (those that will cooperate, at least). The company understands that having 90 percent market share doesn't do much good if the whole market gets killed by Ethernet and iSCSI.
Furthermore, Cisco has decided to enter the Fibre Channel market with the spin-in of Andiamo Systems. This market intrusion is the largest event to hit the Fibre Channel switch space in years, and Cisco's considerable marketing muscle and money will likely represent a huge challenge to the existing Fibre Channel switch companies once its products get off the ground.
Brocade still hasn't had an interoperability epiphany, regardless of competing market forces. The vendor's habit of adding useful but incompatible features to its products damages not only Brocade but Fibre Channel as a whole. When confronted with the interoperability issue, Brocade representatives said it is not in the customers' best interest for Brocade to "dumb down" its Fibre Channel fabric to work with other switches. That sentiment might be true if customers wished to purchase only from Brocade; however, we like choices and believe that purchasers of Fibre Channel switches do too.
QLogic Takes the Prize
We gave our Editor's Choice award to QLogic for its SANbox 2, a midrange switch with outstanding latency and throughput performance, good pricing, and excellent design. The McData Sphereon 4500 came in second with good latency numbers, outstanding price, but with the worst throughput numbers of the three. And though the Brocade SilkWorm 3800's performance was quirky but fine, that unit is simply too expensive compared to its competitors. Brocade's stand on interoperability didn't help its cause, but price was our main concern about that unit.
REPORTS
Analyize In-Line NAC strategies and products.
ANALYTICS Plan and design your enterprise blade server deployments
InformationWeek U.S. IT Salary Survey 2008
Salaries for business technology professionals are falling. Here's what you need to know in order to make good hiring decisions and personal career choices. Download Today
REPORTS
ANALYTICS
Follow 
