SAN JOSE, Calif. With the latest advances in Fibre Channel over Ethernet (FCoE), Cisco Systems hopes all the pieces are finally in place to drive adoption of 10 Gbit Ethernet into rack-mounted servers and switches that represent the mainstream of data center computing.
As many as 250 companies are now beta testing Cisco's Nexus 5000 FCoE switch and the company expects purchase orders to start coming in by August, said Deepak Munjal, a marketing manager in Cisco's data center group.
"10G has been used in the switch for some time but it has been lagging in the last hop to the server," Munjal said. "Now FCoE is ready," he added.
Cisco and other proponents believe FCoE helps drive adoption of 10G Ethernet in the server. A single FCoE card costing as little as $400 per port can replace separate 10GE and 8 Gbit Fibre Channel cards which would cost perhaps twice as much.
A pre-terminated twin axial cabling Cisco and Molex co-developed using an SFP+ connector costs $150 and can carry traffic up to 10 meters, far enough to link the FCoE server cards and switches typically mounted within a single data center rack. The copper cables replace optical links that could cost as much as $3,000.
Separately, Cisco and others are tracking the development of a new generation of 10GBaseT transceivers supporting more commonly used twisted pair cables. Munjal said he expects the transceivers to be ready for systems that could ship by the end of the year. Nevertheless, the 10GBase-T parts will still consume 5W or more compared to about 2W for competing SFP+ connections.
The key issue now is whether users need the 10G bandwidth or will stay with today's Gbit connections that can cost as little as $300 per port to link a server and switch. Several vendors are betting the new capabilities spark a broader 10G market, but others say FCoE won't be ready for prime time until next year.
Intel has rolled out a version of its 10G Ethernet adapter supporting FCoE thanks to open source software developed in part by Cisco. The software runs on the server host CPU.
Emulex and QLogic are in a final test phase of server cards that use off-the-shelf 10 Gbit Ethernet chips and their own internal Fibre Channel ASICs. Cisco started shipping its Nexus switch in June.
The products represent what Cisco sees as a first phase for the converged FCoE link. The IEEE is still developing congestion and bandwidth management standards for a lossless version of Ethernet needed to support multi-hop capabilities for supporting FCoE deeper in the data center network.
"With existing priority flow control mechanisms and jumbo frames, you can build a first-hop solution from a server to the switch," said Munjal. "But you will need the data center Ethernet capabilities in the networks at the IEEE to build a multi-hop solution serving a future merged SAN and LAN," he added.
The IEEE specs should be done by the end of 2009. The basic definition for FCoE will be voted on in August by the T11 group that oversees Fibre Channel standards.