Aid Workers Call Home -
with Laptop and Satellite

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By Jeff Oltmann and Gregg Swanson, HumaniNet
Posted: 8/24/2004

RBGAN under an umbrellaHumanitarian 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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