LocalTalk Over IBM Cabling

This article describes using LocalTalk over IBM cabling.

You can run LocalTalk over the IBM Cabling System. If your customer has installed the IBM Cabling System, there are several cabling types and all of them can be used to construct an LocalTalk network using PhoneNET Connectors and the PhoneNET StarController.
The IBM Cabling System uses three types of cable ends. All the cable ends are color-coded, making it easy to put the right wires to the right posts.
All wires go from a face plate back to a distribution panel in the wiring room. The face plate can either have just a data connector or it can have a data connector and a three-pair telephone Jack. The distribution panel mounts in a standard 19-inch rack. The maximum wire length from an office to the distribution panel is always much less than the distance limitations of a PhoneNET wiring scheme.

The preferred method of attaching to the IBM Cabling System is to use the fourth telephone wire pair in the Type 2 Data Cable. Wire a normal RJ11 wall jack next to the fancy IBM data connector face plate and attach the spare pair to pins 2 and 5 (yellow and black) on the RJ11. (This is the preferred wiring method, but in some places that have the IBM Cabling System the telephone people typically won't let the data communication people touch anything that looks like telephone cabling and most certainly not their new IBM Cabling. Of course, if you have only Type 1 Cabling, then you have no telephone cabling and you have to go to plan B.

The alternate plan is to use a special expensive adapter so that the data cables can be used. Farallon sells a special Data Connector that has an RJ11 socket on it. Farallon Part Number: TE300, IBM Cabling System Line Tap. Two are required for each office to go onto the network, one in the office to provide a place for the modular cable from the PhoneNET to attach into and one at the Distribution Panel. If the network is just four offices on the same floor, you can rig a Passive Star PhoneNET network.

More common is to install a PhoneNET StarController on each floor and to buy the special 19-inch rack-mount StarController Wiring Kit TE347. Normal telephone modular cable can be connected from the TE300 into the RJ11s on the StarController Patch Panel.

This information provided by Farallon Computing.

Published Date: Feb 18, 2012