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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. Such a cable should dramatically reduce the cost of bandwidth measured in $/Mbps, and reduce the Round Trip Times (RTT) from >~ 480 ms for a geostationary satellite, down to 200-350ms by using shorter distance terrestrial routes.

Current State

The throughputs measured to Africa from N. America for the last decade are shown below in the left hand figure. It is seen that not only do African sites lag the rest of the world in throughput being roughly in the state that European sites were over a decade and a half ago, but also they are falling further behind. Further, bear in mind that for Africa, Mediterranean countries and South have the better perfomance and E. Africa is probably the worst off.  Thus the arrival of a terrestrial submarine fibre cable link to the rest of the world for E. Africa is a very significant development.

The minimum RTTs measured from SLAC to African countries in August 2009 is seen below. On the right is seen a map of the over 165 sites that PingER monitors in 50 countries in Africa. The red dots indicate PinGER monitoring sites, the blue are beacon sites that are monmitored by all monitoring sites, and the green are other sites monitored by at least one monitoring site.

The striking number of countries in Eastern and Central Africa with minimum RTTs of >400ms is indicative that they were using geo-stationary satellite links. The new cable should also result in less loss and jitter due to the reduction in congestion caused by the increase in capacity.

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