Providing Internet Search for Low-Connectivity Communities

While the Internet has revolutionized information delivery for most of
us, for many communities in the developing world it remains an
economic and technological challenge to access online resources.  High
charges for telephone and ISP access can quickly grow unaffordable,
and low-bandwidth connections limit the amount of material that can be
viewed per session.  Because phone lines are limited (e.g., a single
phone in a school) it is often difficult to time-share between
Internet and voice.  Furthermore, unreliable network and power
infrastructures can sometimes block Internet access altogether.

We have developed a system called TEK that empowers low-connectivity
communities by providing a full Internet experience using email as the
transport mechanism.  Compared to direct Web access, email can be much
cheaper, more reliable and more convenient in developing areas.  The
TEK system (TEK stands for "Time Equals Knowledge") operates as an
HTTP proxy on the user's machine, enabling users to browse downloaded
pages using a standard Web browser.  New searches are automatically
encoded as emails and sent to the TEK Server, which queries the Web
and returns the contents of resulting pages via email.

Low-connectivity search demands a new set of algorithms over online
search.  We maintain server-side state about each client's page cache,
enabling new results to be expressed in terms of content that has
already been downloaded.  Additional filtering and client-specific
page selection can further improve the relevance and compactness of
results.  We have found that there is a large demand for email-based
search services such as TEK, and we believe that a scalable and robust
service could have a large impact on developing regions.