Communications of the ACM
Sending Data 160 Characters at a Time
Earl Oliver at the University of Waterloo, Ontario, Canada, has an unusual phone bill. Unlimited texting plan or no, most of us would take a few years to send 80,000 messages. Oliver did it in just a few months. Rather than being victim to an unusual obsession, though, Oliver is attempting to bring better communications to rural parts of the developing world--by developing a protocol to send data packed into series of SMS messages.
In rural areas of India, Africa and China, use of SMS has skyrocketed in recent years, as cellphone towers have brought the first reliable telecommunications to previously unconnected areas. "SMS is ubiquitous, reliable and mostly low cost," says Oliver, while data services are expensive and patchy.
Oliver's huge messaging spree was visited on Canadian carrier Rogers, and included tests to probe what happens when you send huge batches of messages, and a data transfer system he built informed by the results. Oliver had to make his system resilient to the fact that his bulk sending tests showed that around 3 percent of messages arrived out of order, thanks to the variable delay between messages.
The question is what kind of data rate can you achieve this way?
From Technology Review
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