alanb@world.std.com (Alan R Bleier) (06/20/91)
We are starting to install a network in a new research building, where people are bringing with them Macs and LaserWriters on localtalk, Suns using ethernet, and terminals with terminal servers. Unfortunately, we tenants of the building were never consulted about data facilities. What we were given was wall plates with an RJ11 phone jack and an RJ45 data jack which is a PDS jack but wired as USOC (because we have a Northern Telecomm phone system?). On the other end in the phone closet each data cable is terminated on a Krone block. The original designers planned to run a token ring network on this equipment, but that won't go in until next year. What we decided to do was use 10baseT concentrators, Farallon phonenet star controllers, and terminal servers, all having RJ45 patch panels (except the Farallon controller, which is RJ11 and will need adapters). Connecting a circuit in the closet just requires a cable from the Krone block to the appropriate patch panel. Each concentrator, server, or star controller will be connected to a thick coax ethernet segment running vertically through the telephone closets on the 6 floors of the building, and on one floor a repeater will connect the whole shebang to an optical fiber with a cisco router on the other end (yes, there are bridges in appropriate places). The plan for the offices was to use different modular cords between 10baseT devices and the wall than we would use for RS232 and Localtalk. The network installer we've been working with told us that RS232, Localtalk, and token ring work with either PDS or USOC wiring because both have the same wiring for the 4 conductors used by those protocols. He also said 10baseT will run on either, but if we run it on USOC we'll need the special modular cords between the 10baseT transceiver and the wall. Now that installation is beginning, the installer seems to have forgotten that the wall jacks are USOC, and that we planned to use different modular cords in the field for 10baseT. I'm hearing second-hand that he is not sure now whether you can run 10baseT through a USOC-wired wall jack, but that may just be the way his wiring people are interpreting what he's saying. Before we meet with the installer and the phone people who own the wiring, I'd like to know the following: 1) Is there any reason why our plan to use a different modular cord in the field for 10baseT would not work (other than the ugliness and impracticality of it) ? 2) If we could convince the phone people to rewire everything as PDS, would their token ring and everything else work on the same wiring, from device in the field to patch panel in the closet? 3) Should we even think about rewiring just the jacks that will have 10baseT? My feeling is that every data jack in the building should be wired the same way. Please correct (gently) any misconceptions in my understanding of this wiring stuff, and email responses to alanb@world.std.com. If there's interest, I'll summarize. Alan Bleier Brigham and Women's Hospital Boston, MA
alanb@world.std.com (Alan R Bleier) (06/21/91)
Thanks to Wayne Sung (sung@mcnc.org) for his email reply about this. We've resolved our problem for now by getting permission to rewire the data jacks we will use. We will negotiate a long term solution later. Alan Bleier