What Is a T-1 Circuit?
Simple Answer – T-1 is a high-speed data circuit with four wires, two of which are used for transmitting and the other two for receiving. The T-1 is capable of transmitting and receiving data at a rate of about 1.5 million bits-per-second (BPS). Thus, the T-1’s data transmission rate is more than 50 times faster than a PC modem operating at 28,800 BPS. Technical Answer – T-1 circuits provide a bandwidth of 1.536 “usable” Mbps on 24 channels of 64 kbps each. This allows for the 8 kbps framing overhead. The aggregation of these channels can be subdivided as a “fractional” T-1 of 64 kbps each. As the cost of T-1 lines has reduced, the move seems to be to use the entire bandwidth rather than parceling the channels/lines out for different applications, or to different locations.
