>On Fri, 22 Jan 1999, Jeff Cochrane wrote:
>> In Uganda we'll be taking an intensive look at our remote wireless
>> connectivity experiment. A research center without telephones has
>> for many months been linked for email to the Internet via HF radio.
Here's a presentation made by UNDP's Daniel Stern on the use of HF radio
for e-mail, which was presented to a workshop on Telecoms and development
organised by the Media Institute of Southern Africa (MISA) to co-incide
with Africa Telecom in Joburg last May:
High Frequency (HF) e-mail at work in the Great Lakes region
By Daniel Stern, United Nation's World Food Programme (WFP) Project
Director in Uganda
High Frequency radio links have enabled development agencies in the Great
Lakes Region to use e-mail for communication between far-flung offices in
areas bereft of telecommunications infrastructure. However this has proved
to be an expensive and labour-intensive operation. A cheaper, faster, more
flexible and less resource-intensive solution has now been put in place by
combining HF with less expensive VHF or UHF technology. The service has
been further improved through the setting up local area networks (LANs) in
field offices, which allow staff to have individual e-mail access.
Automated scanning of radio frequencies has further improved the service by
relieving e-mail radio communications of its dependency on skilled human
operators. The overall impact is better communications that hopefully
allows for more effective relief and development work.
About 18 months ago, WFP's first e-mail-over-HF radio DFMS (Deep Field
Mailing System) was set up in the Great Lakes Region (GLR). Since then, we
have deployed DFMS throughout the region, and have helped to set up similar
systems at WFP head quarters and office clusters in West Africa, the
Greater Horn, Angola and Mozambique. Other UN agencies (Unicef in
particular), as well as WFP implementing partners such as Oxfam, World
Vision, and the Norwegian Refugee Council (NRC), also benefit from this
technology by connecting to our GLR HF network. In so doing, we share costs
and personnel, which makes the network cheaper to run.
The technology has proved to be so efficient that, in Uganda alone, three
commercial ISPs are now offering e-mail-over-radio services. More African
ISPs are to follow their example, I am sure.
Now we have taken DFMS one step further, making the service cheaper and
faster. In so doing, we are providing better communication services to our
staff, particularly those working in remote offices.
'DFMS Plus': DFMS over VHF or UHF radio
WFP now has about 55 e-mail stations in the Great Lakes Region network. We
reached a point that, in one town alone, there were multiple HF e-mail
stations - one for WFP, one for NRC, one for Oxfam, and one for Unicef -
all connecting to the same WFP network hub. Each of these stations required
an investment of about U$10 000, which excluded computers and printers.
Added to which, the HF data link is not particularly fast, and requires at
least one experienced and well-trained radio operator at one end of every
link. Furthermore, each station had to connect to the HF e-mail server in
the respective country offices. So overall the system was a waste of time,
effort and money.
Therefore we looked at a new system - ''DFMS Plus' ' - which uses the same
cc:Mail technology as our current system, but runs over VHF and UHF radio.
With 'DFMS Plus' , we can now connect e-mail stations with off-the-shelf
technology used by amateur radio enthusiasts; a packet radio modem and a
VHF or UHF radio. We run just one HF link to each location - called a DFMS
Point of Presence (POP) - and link stations in the vicinity to the POP
using the cheaper 'DFMS Plus'. In Gulu, northern Uganda, for example, there
is no longer the need for NRC, Unicef and WFP each to buy a U$10 000
station. Only one of the agencies needs to procure an HF station, which
serves as the POP, while the rest can link to the POP using 'DFMS Plus'
stations costing U$1000 each.
This is how Standard DFMS and 'DFMS Plus' compare:
… Runs over HF
… Baud maximum
… U$10 000 for equipment
… One link per channel
… Proprietary protocol
… Runs over Codan HF radio, Codan HF modem
… Needs large antenna
… Needs extensive electricity
… Needs at least one radio operator per link
… Difficult to automate
… Covers thousands of miles
… Deployable in 4 hours
… Runs over VHF / UHF and higher
… Baud standard, 19 200 baud available
… U$1 000 for equipment
… Unlimited users and links per channel
… Shareware protocol (AX25 packet radio)
… A wide range of radios and modems available
… Small VHF / UHF antenna only
… Needs a minimal electrical system
… No radio operators needed
… Automation is standard
… Covers within line-of-sight (typically 50-60 km)
… Deployable in minutes
Cheaper, faster, no operators needed, automated; what more can you ask for?
Well, the 'DFMS Plus' system does have some drawbacks, one of them being
that the system covers far shorter distances (50-60km for VHF / UHF) than
HF DFMS. However, relatively cheap equipment called "digipeaters" are
available which act as a relays, just as VHF voice repeaters do, so we can
still cover large areas by linking digipeaters. This technology is used by
radio amateurs to build networks made up of thousands of nodes covering the
whole of North America or Europe, for example.
Not only can 'DFMS Plus' technology be run from fixed or mobile stations,
it can even be operated from hand-held radios. So why did we need to
implement all those HF DFMS stations in the first place? Well, in most
locations, we still need an HF station for voice and security
communications, as well as one HF e-mail system for every POP, so the HF
equipment is not totally obsolete.
E-mail on every computer
Another problem we faced was that larger field offices could still only
send and receive e-mail from one computer; the one in the radio room. This
posed a number of practical problems. That was until last month, when we
set up our first "cheap" local area network (LAN) in a WFP field office at
Ngozi, installed a cc:Mail post office, and linked the field office up to
the country office in Bujumbura via HF radio. The Bujumbura office itself
links to our Kampala office, also using HF radio, and in so doing avoids
paying an estimated U$50 000 per month phone bill which the Bujumbura
office would run up if its was connecting to Kampala by telephone.
Automating the DFMS HF clients and the servers.
Up until recently, each HF e-mail station required two radio operators to
initiate the link: one at the client - or remote - end, and one at the
server housed at the country office. This meant that e-mail could only be
sent when both radio operators where in their respective radio rooms. By
implementing some simple HF network management procedures, we have now
automated either the server or the client, so that one or other can call in
without a radio operator being present on the other side.
Let me give some examples. WFP's Kampala warehouse has a DFMS HF server
station, which is unmanned. It is set up to scan the frequencies
continuously, so that clients can radio in at any time of the day or night
to pick up and / or drop e-mail. The client simply connects to any of the
frequencies being scanned by the warehouse server. Similarly, Unicef's
office in Kisangani (the client) is also scanning frequencies
automatically, which allows WFP Kampala to pick up and deliver e-mail to
the Unicef client, even if no one is in the Kisangani radio room to monitor
the link. Unicef Kisangani simply knows that e-mail is picked up and
dropped four to five times a day.
E-mail at our Kinshasa office is also fully automated, so that WFP / Unicef
in Brazzaville, or any DFMS station in Congo Brazzaville, can pick up and
drop e-mail at any time by connecting to WFP Kinshasa. Kinshasa is, in
turn, linked via HF radio to the e-mail server at the WFP's office in
Kampala. Kampala picks up and drops their e-mail throughout the day, before
going on automatic scan each evening, which allows Kinshasa still to drop
its e-mail. This night time automation is particularly important as
Kinshasa is two hours behind Kampala.
The combination of 'DFMS Plus', cheap LANs, and automated DFMS services are
providing a radically better service to our users, which will inevitably
improve our communications as a whole. I hope this will ultimately help WFP
to provide a better and cheaper service through its relief and development
PO Box 8828, Bachbrecht, Windhoek, Namibia
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