RS-232 Cable for the Pipeline 25

The Pipeline 25 does not support Telnet or SNMP, the two ways normally used to manage a unit remotely. It is possible to setup and configure the unit from a remote Pipeline 50 or better, but it is not possible to manage it from your desktop very well.

The control interface for the Pipeline is through a standard DB-9 terminal connector on the unit. You are supposed to connect this terminal to your Mac or PC serial port, and communicate with it through a terminal emulation program, like Z-term, Microphone, etc. The only problem with this is that the Pipeline may be located at some distance from your computer. In my case, it's about 50 feet away in a closet. This is how I overcame the no-telnet, no-SMTP issue on the Pipeline 25.

I ran one extra 4-pair cat5 cable from the RJ-45 punchdown panel in the closet (where the enet hub and pipeline is located) to the place my computer is located. At the wall by my computer, I wired an RJ-45 connector per T568B, all 8 wires.

I got two DB-25 to RJ45 connectors, (which were off the shelf at Frys), one Male, and one Female. These are DB-25 shrouds and connectors, with an RJ-45 connector in the shroud prewired with either male or female pins on the wires. You punch the pins from the RJ-45 into the DB-25 connector frame and snap the shroud over it, so you have a little DB-25 male or female connector with an RJ-45 jack where the wire would normally go.

I wired them to match the Mac modem cable (used all 8 wires). The wiring I used is shown below. I'm following a Mac requirement, but it should work the same for PCs. The constraint is to only use 8 of the 9 standard RS-232 signals. Macs only use 5 anyway. There is probably nothing magic about the colors I used, although I selected to put RxD and GND on one twisted pair (R,G will go to Blue,BluStripe on the cat 5 cable). Obviously, both connectors need to be wired the same. 

Signal
Name    Pin    Color
------  ---    -----
GND      1     not used 
TxD      2     Yellow
RxD      3     Red
RTS      4     Blue
CTS      5     Gray
DSR      6     Orange
GND      7     Green
DCD      8     Brown
DTR      20    Black

Back at the Mac, I just plug my a standard Mac modem cable from the Mac's serial port into the female DB25, and use a standard patch cable to go from the DB-25 to the wall plug. In the closet, I use a short patch cable from the RJ-45 punchdown to the male DB25, then plug the DB25 into the DB25 to DB9 connector supplied by Ascend with the Pipeline Router. Essentially, I have configured a 50-foot long serial modem connector.

Shown at left is the Mac Modem cable (top), connected to the DB-25 to RJ45 connector (Red), with the patch cable down to the wall plug. The other red and white lines are part of the "picasso" version of the Mac logo which is on the mousepad that I took these pictures on. It was an accident, OK?

Result: I can configure or monitor the Pipeline from my desktop, even though it's located in a closet 50 feet away. If I put a DB25 A/B switch in I could use my modem easily too. As it is, I just switch the cable when I want to look at the Pipeline.

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