Sven Kemps writes from the Netherlands:
> My university (University of Nijmegen, the Netherlands) is
> considering funding an e-mail connection for an university in
> Eastern Congo. No telephone lines are available at the site. An
> alternative for an e-mail connection via HF Radio would be a
> store-and-forward system using Inmarsat. Does anyone on this list
> have any experience with such a solution?
Both the HF and satphone systems will utilize basically store and
forward technology, yes? Another alternative in Congo may be
cellular, so don't forget to check on that -- coverage is reportedly
fairly extensive there. I know of one person working in Kinshasa
with data radio equipment (Codan I think) who could probably advise
you further on all of this -- let me know if you want to be
contacted, and I'll facilitate.
Agrhymet in Niamey for some time used the Inmarsat solution with Fido
technology (store and forward), though I assume they no longer do so.
It worked well and economically (relatively speaking) for them.
Regarding the interesting question of comparative costs, here's an
estimation procedure. These are basically back-of-the-envelope
calculations based on field experience. Others can offer corrections
and additions based on their own local experience.
Inmarsat charges per minute, about $3 when last I checked, down from
quite a bit more than that some years ago. Assuming a 9600 b(its)ps
effective throughput (optimistic, I'm told), you could transmit up to
1200 bytes of data (roughly half a printed page) per second. Add
maybe a minute to each transmission for software handshaking,
transmit confirmation, signoff. So for a rough comparison, figure
transmitting 10 pages in a day, 20kb, 20 seconds, plus a minute,
you'll be billed for 2 minutes daily, 25 days in a month at say $6
per day, $150 per month. Someone who knows more about Inmarsat
might say a word about compatibility issues -- I've never used the
service myself. Add $20 monthly for an Internet account somewhere
in the world.
HF radio would be by the kb, not by time, so at US$0.3 per kb,
that's $6 a day (surprise), $150 per month. I'm told HF radio rates
are dropping, however, and lower rates can be negotiated. Price
includes the Internet access account. All this assumes you have a
provider in the area where you'll be based. From Eastern Congo you
might link to a Uganda provider, but the law on that is quite fuzzy
right now. Confirmed range on the World Food Program system
is Kampala to Dar es Salaam, which pointed in the other direction
would reach well beyond Kisangani. Inquire at www.bushnet.net or at
www.imul.com. Others may suggest additional service providers. An
alternative in Congo might be MAF. Check www.maf.org if you're a
Inmarsat equipment runs maybe $4000 to $5000, and lets you chat with
any other phone in the world at the above rate. Permits web
browsing, albeit slowly, best with no graphics.
HF radio equipment, not counting the computer, might run you $8000.
You can talk voice to other radios. Not really suitable for web
browsing with graphics, and slow even without graphics, since
effective throughput is about 2400 bps (optimistic).
All bets are off with sunspots. 8*)
The above are based on 10 pages per day. For an entire university,
you might expect higher volume (but maybe not, in my experience,
depending on how it's controlled and budgeted). I received a report
this morning from someone who prefers not to publish on Afrik-IT. He
compares satphone rates versus HF radio bulk negotiated rates, with
HF radio less than 10 per cent of satphone costs. I have no way to
verify this information. Volume of about 40 megs a month is supposed
to run maybe $2,000 per month, pretty close to what my parameters
above would suggest (that overhead for handshaking becomes less
important on high volume transmissions).
The above are simply my notes from many conversations with people in
the field. Hopefully the experts will chime in and offer
corrections and additions, or will communicate with you privately.
Eastern Congo, by the way, is probably a place where a sneakernet
would be difficult to implement.
Jeff @ Washington
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Arlington, VA 22209 USA
Tel 1-703-235-5415 Fax 1-703-235-3805