• United States

Cat-6 may go farther

Jan 08, 20042 mins

* 10 Gigabit Ethernet over Category-6 wiring could go 100 meters

Last month I talked about some of the objectives of the IEEE study group looking into running 10 Gigabit Ethernet over unshielded twisted pair wiring. It turns out that some members of the group are looking to push those objectives a bit further.

Specifically, some organizations think they can push the distance supported by Category-6 cables to 100 meters, instead of the minimum 55 meters stated in the group’s goals.

Krone in November presented the results of tests of Cat-6 cables that showed they have a capacity of 20G bit/sec. In the presentation, Krone said that in its tests the company arranged six cables around one in the middle, and tested the cables both in a metal conduit and on the floor. The tests showed that transmitting 10 Gigabit for 100 meters was possible without the need for mitigating alien crosstalk.

In a separate presentation, Pennsylvania State University also noted that there is “every indication that 10Gbps transmission over 100m of CAT-6 is possible” given the allowed bit error rate being considered for the standard.

However, Category-6 cabling is still a different wiring than is installed in a lot of places. Many organizations have installed Category-5E for their Gigabit Ethernet links, a point raised by Mike Bennett of Lawrence Berkeley National Laboratory in his November presentation.

He argued for running 10 Gigabit over Cat-5E, even if it were only 50 meters; that way, a data center wouldn’t have to be re-cabled to upgrade from Gigabit Ethernet. But that is not currently one of the study group’s objectives.