I am trying to learn as much about T1s as possible. From what I have learned so far, I believe there are two types, a "regular" T1, and then a PRI, or Channelized T1. Is this correct?
We can say that generally there are 3 T1 types
In unchannelized operation, a T1 encapsulates the entire T1 payload (1536000 bits/second) .In channelized operation, a T1 port may be configured with up to N separate data streams (N = 24 for a T1 port). Each data stream may include any combination of time slots, either contiguous or not. Of course, each time slot may be included in only one data stream.
An ISDN PRI T1 implementation has 23 B channels and a D channel. As with BRI, each of the B channels has 64- kbps bandwidth available. The D channel, however, is also a 64-kbps channel (unlike BRI).
HTH, please do rate if it does help,