The Atlantic Cable website often receives requests for historical data on signalling speed and traffic capacity of long distance cables, so I've summarized here some improvements in cables over the last 150 years. The majority of cables listed are Atlantic crossings to give consistency to the results.
| Cable |
Year |
Speed or Capacity |
| Atlantic, Ireland-Newfoundland |
1858 |
A few words per hour |
| Atlantic, Ireland-Newfoundland |
1866 |
6 - 8 words per minute |
| Long cables with automatic transmitting equipment |
1898 |
40 words per minute |
| Newfoundland-Azores |
1928 |
2,500 characters per minute (~400 wpm) |
Atlantic, TAT-1
(first repeatered cable) |
1956 |
36 telephone channels |
| Atlantic, TAT-2 |
1959 |
48 telephone channels |
| Atlantic, CANTAT |
1961 |
80 telephone channels |
| Atlantic, TAT-3 |
1963 |
138 telephone channels |
| Atlantic, TAT-4 |
1965 |
138 telephone channels |
| Atlantic, TAT-5 |
1970 |
845 telephone channels |
| Atlantic, TAT-6 |
1976 |
4,000 telephone channels |
Note: In 1978, before the inauguration of TAT-7, an article in the Times noted that:
“More than half of all international telephone calls between Britain and the rest of the world go by undersea communications circuits.”
The rest were transmitted by satellite, but with the advent in 1988 of TAT-8, the first transatlantic fiber optic cable, the balance moved rapidly to cable. Since then, satellite has played only a relatively minor role, as the article went on to predict.
[Pearce Wright. “Cable and satellite systems maintain rivalry.” Times (London, England) 4 Apr. 1978: IV.] |
| Atlantic, TAT-7 |
1978 |
4,000 telephone channels |
Atlantic, TAT-8
(first fiber-optic cable) |
1988 |
280 Mbit/s (40,000 telephone channels) |
| Atlantic, TAT-9 |
1992 |
2 x 565 Mbit/s (each 80,000 telephone channels equivalent) |
| Atlantic, TAT-10 |
1992 |
2 x 565 Mbit/s |
| Atlantic, TAT-11 |
1993 |
2 x 565 Mbit/s |
| Atlantic, TAT-12/13 |
1996 |
2 x 5 Gbit/s |
| Atlantic, TAT-14 |
2001 |
4 x 16 x 10 Gbit/s, 640 Gbit/s system capacity (9,700,000 telephone channels equivalent).
Note: TAT-14 has four fiber pairs, each carrying 16 wavelengths. Each wavelength carries a 9.6 (nominally 10) G signal, giving a 640 Gbit/s total capacity. |
| Atlantic, VSNL (TGN) |
2001 |
2 x 2,520 Gbit/s |
| Hibernia Atlantic (cable commissioned in 2001 and partially upgraded in 2007) |
2007 |
10 Gbit/s on transatlantic section, 40 Gbit/s from Boston to Nova Scotia.
System capacity 1.9Tb/s, 7.68Tb/s on upgraded section |
| Atlantic, GTT Express (formerly Hibernia Express) |
2015 |
100 Gb/s x 100 wavelengths. Maximum capacity 53 Tb/s |
Return to the Atlantic Cables index page |
