T1, T2, T3 White Papers
T1, Where Does the "T" Come From?
Overview The story of the "T" in T1 has its roots way back in 1917, when AT&T deployed the first carrier system, called the "A" system. A total of 7 A-systems, providing four voice channels over an open wire pair, were ever deployed. Then came successive analog frequency division multiplex systems named B, C, D, and so forth. Few of these carrier systems ever saw commercial service. AT&T, being a monopoly, could well afford many dogs. A notable success is the "L" system, providing 600 (L1) and later 1800 (L3) voice channels over a pair of coaxial cables, in long haul service from 1944 to 1984, until breakup of the Bell System forced AT&T to migrate to optical fiber. The last of the analog carrier system is the "N" system and its variants, providing 12 voice channels for intracity short haul. Along with the even more forgettable "O", "P", and "U" systems, the emergence of "T" killed them all.
| Publisher | Data Comm for Business Inc. | File Format | HTML |
|---|---|---|---|
| Date Published | August 2003 | Downloads | 9 |
| Format | White Papers | ||
| Topics | |||
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