I have been biting my lip so far about who has the biggest capacity, but
since someone asked about South Africa ...
I don't know how one would define a 'hub', but South Africa's links are well
depicted by Greg Massel at
Which is a large .gif file, so [log in to unmask] could e-mail it on request.
We have two large providers, Internet Solutions and Uunet/Internet Africa,
each with 2.5 - 3.5 mbps links. Our telco has a 2 mbps link. There are a few
other providers with 384 kbps and higher links. The capacity between South
Africa and the United States/Europe seems to be about 9 mbps
(conservatively). This is quite a high figure, considering the main Uunet
line connecting the US to Europe is 45 mbps, but feeds into a number of
We know that providers have a reasonably high line utilisation, so can
estimate the traffic. The figures are not static, but probably peak at about
85% at times. One can also obtain exact figures for the academic network,
Uninet, since it publishes them on its website (www.frd.ac.za). Their
utilisation is very high, as they work on a tight budget and have a lot of
automated off-peak transfers, for example to update mirrors on their ftp
The chart will also show direct links between South Africa and other
countries in Southern Africa, so reasonable traffic estimations could be done
for those countries too. For instance, at present, the Mozambique tcp/ip
traffic comes via Uninet, and so can also be read directly off the
www.frd.ac.za live traffic updates.
A final point, of academic interest, is that as the networks have matured, a
few strategies have been developed to reduce the percentage of traffic which
has to go international. There has been better peering between providers,
some established mirror sites, more sophisticated caching, and better local
Of course, in my line of work, I am working towards the day when there is so
much growth and there are so many developments under way, that it will be
hard to tell which countries in Africa are generating the most useful traffic.
Project Manager: Connectivity Southern Africa
International Development Research Centre (IDRC)
ph: +27-11-4033952 fax: +27-11-3395050