Chelsio Communications and Tehuti Networks today are separately announcing the first 10GBase-T adapters, which run 10 Gigabit Ethernet over copper wiring.

The adapters send 10 gigabits per second over Category-6 or Category-7 copper cabling, adhering to the IEEE 802.3an standard finalized last year.

Chelsio is unveiling two 10 Gigabit cards, the S310e-BT storage adapter and the N310e-BT server adapter. The cards auto-negotiate between 1Gbps and 10Gbps. The company says the dual-speed capability should help with upgrading servers that may be hooked up to Gigabit switches today, but would be upgraded to 10 Gigabit switches in the future.

The ASIC in the storage adapter offloads TCP/IP, iSCSI and iWARP RDMA processing from the host system. The storage adapter costs $2,000; the server adapter is $1,300. Both are expected to begin shipping in March.

Tehuti, meanwhile, is introducing three additions to its adapter reference design lineup - the TN7588-S, a single-port 10GBase-T NIC; the TN7588-D, a dual-port 10GBase-T NIC; and the TN7585-D, a dual-port CX4-based 10 Gigabit Ethernet, low-profile server adapter. The CX4 adapter runs on twin-axial copper cables, via the IEEE 802.3ak standard.

The CX4 adapter is currently sampling to OEM customers. It is expected to ship in the second quarter of this year for $500.

Tehuti plans to show the 10GBase-T adapters running at the BICSI 2007 conference in Orlando next week.

Both vendors are using transceivers made by start-up chip designer Teranetics. Both use the PCI Express host bus interface.

Jeff Caruso is site editor at Network World.