60ms cross continent
Mark Tinka
mark.tinka at seacom.com
Wed Jul 8 07:05:46 UTC 2020
On 7/Jul/20 21:58, Eric Kuhnke wrote:
> Watching the growth of terrestrial fiber (and PTP microwave) networks
> going inland from the west and east African coasts has been
> interesting. There's a big old C-band earth station on the hill above
> Freetown, Sierra Leone that was previously the capital's only link to
> the outside world. Obsoleted for some years now thanks to the
> submarine cable and landing station. I imagine they might keep things
> live as a backup path with a small C-band transponder MHz commit and
> SCPC modems linked to an earth station somewhere in Europe, but not
> with very much capacity or monthly cost.
>
> The landing station in Mogadishu had a similar effect.
The early years of submarine fibre in Africa always had satellite as a
backup. In fact, many satellite companies that served Africa with
Internet prior to submarine fibre were banking on subsea and terrestrial
failures to remain relevant. It worked between 2009 - 2013, when
terrestrial builds and operation had plenty of teething problems. Those
companies have since either disappeared or moved their services over to
fibre as well.
In that time, it has simply become impossible to have any backup
capacity on satellite anymore. There is too much active fibre bandwidth
being carried around and out of/into Africa for any satellite system to
make sense. Rather, diversifying terrestrial and submarine capacity is
the answer, and that is growing quite well.
Plenty of new cable systems that are launching this year, next year and
the next 3 years. At the moment, one would say there is sufficient
submarine capacity to keep the continent going in case of a major subsea
cut (like we saw in January when both the WACS and SAT-3 cables got cut
at the same time, and were out for over a month).
Satellite earth stations are not irrelevant, however. They still do get
used to provide satellite-based TV services, and can also be used for
media houses who need to hook up to their network to broadcast video
when reporting in the region (even though uploading a raw file back home
over the Internet is where the tech. has now gone).
Mark.
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