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The Seacom undersea fibre optic cable plugging East Africa into high speed Internet went live Thursday July 23, 2009. See the BBC and CNN reports. This should enable the improved performance (increased bandwidth, reduced Round trip Such a cable should dramatically reduce the cost of bandwidth measured in $/Mbps, and reduce the Round Trip Times (RTT) , and less congestion and thus jitter. Potentially this can affect a large populationfrom >~ 480 ms for a geostationary satellite, down to 200-350ms by using shorter distance terrestrial routes. The minimum RTTs measured from SLAC to African countries in September 2008 is seen below. 
The striking number of countries in Eastern Africa with minimum RTTs of >400ms is indicative that they were using geo-stationary satellite links. The new cable should also result in less jitter due to the reduction in congestion caused by the increase in capacity..
At the moment the SAT-3/WASC/ fibre has been in place for some time and connects up several countries on the W. Coast of Africa. The Seacom line is not the only fiber-optic cable project on Africa's east coast — others include the Eastern Africa Submarine Cable Systems (EASSY), The East African Marine System (TEAMS) and Lion — but it will be the longest and have highest capacity (1.28 terabytes per second). The EASSY and TEAMS are designed to build out African telecommunications networking, but Seacom is the only line that directly will connect east coast urban areas in Kenya, Madagascar, Mozambique, South Africa and Tanzania to France and India. TEAMS landed in Mombasa early June 2009 and is currently undergoing testing while EASSY and Lion are expected to be operational by mid-2010. Maps of the various fibres is shown below and more details are available here.
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