Potential for collaborative caching and prefetching in largely-disconnected villages

ABSTRACT

In a world becoming ever more reliant on the power of information, bringing data connectivity into developing regions is becoming an important way to lift these regions out of poverty by educating and informing the population. Although many of these regions are not likely to receive the infrastructure to support fully wired (or even wireless) networks, existing cellular and delay tolerant technologies allow limited connectivity. In this paper we show that usability of highly disconnected networks can be increased through collaborative caching and data prefetching techniques. We focus on decreasing the miss rate of pages fetched in both general web access as well as more specialized education applications. We evaluate our schemes by running trace-driven simulations of internet traces from Cambodia and logs from Princeton University's Blackboard courseware web servers. Our caching and prefetching strategies in these environments show improvements in miss rate of up to 90% over more traditional approaches.

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INDEX TERMS

Primary Classification:
  J. Computer Applications
  J.1 ADMINISTRATIVE DATA PROCESSING
      Subjects: Education

Additional Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.1 Network Architecture and Design
          Subjects: Store and forward networks

General Terms:
Design

Keywords:
caching, delay tolerant networking, prefetching