Towards Low-Cost Data Communication for Developing Regions

Many parts of the world are without realistic access to a data network, despite having a cell phone infrastructure. Even rudimentary point-to-point data communication creates new avenues for growth in important areas like healthcare, education and microfinance. Recent work has shown the viability of transmitting data over a GSM voice channel by disguising the ”data channel” as a human voice engaged in a phone call, but these works have avoided the practical issues of cost and proliferation. We seek to build a lightweight, low-cost data communication platform for deployment on existing or growing technologies in the developing world. We present the successes in failures of our platform, MicroModem, which aims to be a cheap data modem for the GSM voice channel. Although MicroModem is not yet functional, our primary contribution in this paper is a better understanding of the GSM voice channel and directions for building such a system.