Mysticom sets watermark for 10-Gbit Ethernet over copper

Mysticom sets watermark for 10-Gbit Ethernet over copper
SAN JOSE, Calif. — Mysticom Inc. demonstrated a transceiver that set a new watermark for high-end Ethernet signaling over copper wires at the Communications Design Conference this week, sending 10-Gbit/second signals over 25 meter copper using Infiniband cables, and over 10 meters using Category 5 unshielded twisted pair.

Pushing full 10-Gbit/s Ethernet over 100 meters of standard Category 5 copper cables is currently a Holy Grail in Ethernet design, and a goal that some — including Mysticom's engineers — say cannot be commercially reached with the current standard.

Category 5 cables are the most inexpensive and widely used cables linking systems in businesses today. But attenuation and crosstalk of high-frequency signals on the unshielded cables prevent the fast links and require a move to more expensive optical fiber or the new thickly shielded Infiniband copper cables.

Mysticom's new transceiver uses multiple 3.125-Gbit/s Ethernet serializer/deserializer (serdes) channels which can also push the signals up to 70 inches over copper traces on a standard FR4 printed circuit board.

Ultimately, Mysticom believes it can push 10 Gigabit Ethernet up to about 50 meters over copper. However, the commercial goal for its next-generation transceiver is for longer optical fiber stretches rather than copper ones.

"We don"t see any customer interest in 10G Ethernet over 100 meters of Category 5 wire, but we do have interest in transceivers for longer fiber and Infiniband cable links," said Amir Bar-Niv, director of engineering at Mysticom (Mountain View, Calif.).

Mysticom's next-generation transceiver, which has already taped out, will replace the XAUI interface with a proprietary encoding scheme which will enable signaling to extend 600-to-800 meters over low-grade fiber.

One router maker is interested in that capability as part of a 10G Ethernet backplane, and a switch maker wants to use the chip for fiber or Infiniband cable links between distributed switches in a data center which might stretch between multiple buildings.

Bar-Niv estimated the new transceiver would probably allow 10G Ethernet signaling to extend about 20 meters over Category 5 cables.

Looking further ahead, Mysticom's follow-on effort will be to design a 10 Gigabit Ethernet based on 5-Gbit/s serdes channels. "We don't see a lot of demand for that now, but in four years time, we probably will," Bar-Niv said.