East Africa Fibre Connectivity- Heads up

Fred Baker fred at cisco.com
Wed Aug 5 08:52:50 CDT 2009


That is very much to be expected, if nothing else due to pent-up  
demand. The existing vsat infrastructure tends to be pretty saturated,  
meaning that users experience a lot of loss as well as delay. What if  
they stop losing traffic?

War story: in 1995 I found myself sharing a podium with Phill Gross,  
who was then a VP with MCI. He was more or less apologizing for the  
behavior of his network. They had recently upgraded to a then-new-and- 
gee-whiz OC-3 infrastructure, in many places using parallel bandwidth,  
and were dropping a lot - he reported one link to be dropping 20%. So  
they then upgraded the whole thing to OC-12 - and fiber that was OC-3  
was replaced with an OC-12. They presumed that this would give them  
75% overprovisioning at worst. What they actually saw was that those  
links that had been dropping 20% were now dropping 4%. TCP observed  
that it was not getting crunched into the ground, and started opening  
its windows.

The other big issue with satcom is of course delay, and with  
conversion to fiber the delay plummets. That means that where you  
might have had <mumble> connections running at <low> average speed due  
to RTT, the average connection speed for the same session is instantly  
multiplied by <old-RTT>/<new-RTT>. That gives the user time and  
incentive to click again during that same time window - new load.

Price is very important, of course, but I suspect your 100 MBPS is  
explainable by simple network dynamics.

On Aug 5, 2009, at 6:13 AM, Raymond Macharia wrote:

> Hello all,in the last two weeks or so providers in East Africa,  
> particularly
> in Kenya where I am, have been moving from Satellite to Fibre for the
> internet Back bone connectivity. From where I am I have seen an  
> upsurge of
> about 100Mbps in the last two days from my users. It would be  
> interesting to
> know if anyone out there has seen an increase in traffic from this  
> region
> and by how much. There is more to come as providers are cutting  
> prices and
> adding bandwidth to their networks.
>
> Best Regards
>
> Raymond Macharia





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