>> You're talking about a t3 right? I don't think there would be any comparison. If you implement a t3, I am sure it would cost several thousand dollars every month.
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>Pardon my ignorance but what is a t3 ?
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T3 is a higher-bandwidth digital point-to-point connection; it provides the equivalent of 28 T1 connections (about 44.7Mbps; it can be subdivided in a variety of ways. It's the equivalent of 672 B channels from the perspective of ISDN; in most cases, discussing ISDN, people are talking about BRI, which is 2 64Kbit B channels and a 16Kbit D channel used for out of band signalling and control. In all cases, we're talking raw data rates; a B channel with framing and other overhead provides about a 56Kbit data channel; two B channels can be combined to yield about 112Kbps.)

Unlike ISDN, T-connections are sold on a distance basis; the longer the distance between two points, the greater the cost. Also, T-Carrier connections are strictly point-to-point; ISDN services can conect to pretty much any other ISDN node; each ISDN connection has a 'phone number' associated with it.

A somewhat dated, but fairly comprehensive, overview of the technoligies can be found in Megabit Data Communications, A Guide for Professionals by Powers and Stair, published by Prentice-Hall around 1990. While the price guidelines are dated, it covers the various widely-available technologies in good detail, and does it in under 400 pages. It's worth checking your local library to see if it's available.

>Regards,
>
>Gerard