Aid Workers Call Home -
with Laptop and Satellite
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By Jeff Oltmann and Gregg Swanson, HumaniNet
Posted: 8/24/2004
 Humanitarian teams are accustomed to checking email and
viewing Web sites on desktop or laptop computers, usually
in an office or hotel. Many now do it in the most remote
areas – over a portable satellite terminal. But some
creative users have discovered how to "call home" using
their laptop and an RBGAN data terminal.
The promise of VoIP. Since the first phone lines and transoceanic
cables were laid, aid workers have always sought better,
cheaper ways to communicate from remote locations. Voice
over Internet Protocol (VoIP) is rapidly changing the landscape
of long distance calling. HumaniNet has been monitoring
it to see how it can benefit our members.
Using VoIP, a computer user can place phone calls over
the Internet. VoIP bypasses the traditional phone system,
which is expensive, unreliable, or unavailable in many
parts of the world. VOIP users can make phone calls when
the local phones aren’t working, as long as they
have an Internet connection. They can also bypass the high
prices of long distance phone calls in many developing
countries, which can exceed $5 per minute.
VOIP and satellite. A growing number of aid and relief
personnel use RBGAN satellite data terminals (modems) to
connect their computers to the Internet from remote locations.
The RBGAN (see our article "RBGAN – the Next
Step Toward Portable Broadband") has proven to be
rugged and reliable, delivering emails for as little as
3 cents each for small text messages. Several industry
experts believed that VoIP would not work over satellite,
primarily because the "latency," or delay in
the satellite signal, would scramble the data packets that
the Internet uses to send and organize messages and files.
So we decided to try "digital conversations" over
the RBGAN. The results exceeded all expectations. We wanted
answers to three questions:
- Does it work at all?
- If so, what is the sound quality
of the calls?
- What does it cost?
The test. We purchased and installed Crystal Voice Live,
an inexpensive and easy-to-install "voice over Internet" software,
on computers in the US and scheduled test calls with partners
in West Africa, who installed the same software. With the
software and a headset or microphone/speaker, the computer
becomes what is called a “soft phone." When
you contact another subscriber, their computer rings, instead
of their telephone.
For each test, we initially used broadband connections
at both ends to establish a baseline for kilobyte usage
and sound quality. For the second phase of the test, our
partners in West Africa used RBGANs to connect to the Internet
via satellite.
The tests were highly successful, since we were able to
answer all three questions. VoIP over RBGAN worked impressively
and was easy to use. Sound quality was consistently 4/5
or 5/5 on the HF radio rating scale.
The calls occasionally had slight imperfections due to
the technical challenges of traveling over the Internet
and over a mobile satellite connection. Even so, the software
adjusted quickly and effectively. The voice quality was
good to excellent, better than comparable calls using a
landline or cell phone to call between the locations. One
of our field testers was “very impressed” and
felt that the quality was “very acceptable.”
We also calculated the cost of our test calls. RBGAN users
are charged by the amount of data sent through the satellite,
and VOIP moves a lot of data over the Internet connection.
Our costs ranged from USD $0.81 to USD $1.83 per minute
of talk time, with an average cost of $1.52 per minute.
With three-way conferencing, the cost per minute rose to
$2.32. There are many possible reasons for the variation
in data rates, and thus cost; but our tentative conclusion
from the tests is that calls using this VoIP service over
RBGAN should not usually exceed $2.00 per minute. This
is based on an available rate of $9.60 per megabyte.
Our test calls were between West Africa and the U.S.,
but costs should be similar for calls from other locations
with RBGAN coverage. Although this is not inexpensive,
it is worth considering in locations where phone systems
are expensive or unreliable. We also anticipate that RBGAN
costs to drop in the future, reducing the cost of VoIP
calls.
Not for everyone – but lower phone bills
are possible. Clearly, only users who need voice capability in the field
would benefit from VoIP/RBGAN using this software and service.
Obviously, Iridium, Thuraya, or Globalstar satellite phones,
not to mention cell phones, would also provide voice telephony.
However, anyone in the world with broadband or dialup
Internet access will find that VoIP can generate significant
long distance savings. Humanitarian workers can use a low-cost
VoIP subscription in the office and in the field, using
RBGAN. Most services enable a subscriber to call any phone
number – not just other subscribers – for as
little as 3 cents per minute.
The test has underscored the need for a benchmarking study
to compare different VoIP services. Not all use the "softphone" concept,
requiring the user to purchase a connector or "black
box." The cost recovery is usually very fast, however.
HumaniNet is in the early planning for a study of this
sort.
For readers who would like a technical explanation of
VoIP, please see the Wikipedia or
HowStuffWorks.
If you have questions about this article or field communications
generally, please email us at info@humaninet.org.
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