Ethernet Connectors on Workstations and PCs
Brian Carpenter CN/CS
CERN, like many sites, is progressively converting its Ethernet LAN infrastructure from the old thin-coaxial cable standard (IEEE 802.3 10base2) to the new twisted-pair standard (IEEE 802.3 10baseT). This conversion has started and will hopefully be largely complete within three years.
As this recabling proceeds building by building, workstations and PCs which have only coaxial (10base2) connectors will require convertor boxes to connect them to the new 10baseT system. Conversely, workstations with only 10baseT connectors will require the same convertors to connect them to the old 10base2 coaxial cables. These convertors require a 220 V power supply. However, workstations with transceiver connectors (DB15 AUI connectors) can be connected to either cabling system by a suitable transceiver. Transceivers are cheaper than convertors and do not require separate power.
For more technical details, including where to obtain convertors and transceivers, please see CN/CS/155 (The CERN Internal Network Brochure, November 1993, available from the User Consultancy Office in Building 513). Convertors cost about 400 CHF and transceivers with cables about 150 CHF. Users are normally charged for such items, but they will be funded by CN when users are forced to add them by the recabling of a building.
To minimise the total number of convertors ultimately required at CERN, all users and suppliers are advised that: