In the interest of complicating things further, I think you have NIU and smartjack backwards in your explanation...the smartjack has alarm lights and can be remotely looped by the telco via ESF loopcodes; the NIU (also known as an RJ48X) is the dumb wiring box. In my experience, smartjacks are placed on the line at the MPOE, and extended demarcs are presented on RJ48X jacks. In the past few years, I've seen more and more T1s delivered without a smartjack; the circuit is simply presented on the RJ48X, which will loop back towards the telco if there's no cable plugged into it. I'm not in provisioning, so I don't know whether or not telcos charge more for smartjacks than they do for RJ48X jacks, but if you can get one, do. Having to drive to the office to yank a cable so the telco can test your line can kinda suck. -C On Jul 22, 2004, at 11:31 AM, Michel Py wrote:
What is the "NIU"?
The box that converts the signal from the street (that can run for miles) into the signal you find on the smartjack (that can only go a few hundred feet). Although I don't like the term, it's some kind of a digital modem. The smartjack is dumb (no lights); the NIU is the brains of the smartjack, what has the lights and can be looped.