Establishing Trust for Computation Offloading

Computation offloading can extend the battery lifetime of a portable device by migrating computation to grid- powered servers. The server may charge the portable device for the computation performed, thus providing offloading as a service. The portable device has to trust that the server has indeed performed the computation as claimed. We propose a protocol to establish trust for computation offloading. The protocol uses two keys to establish trust. The first key is part of the input for the computation; executing the program with the first key generates the second key. Without executing the program, it is difficult to generate the correct second key. We implement an algorithm that meets the requirements of the protocol on an HP iPAQ PDA and a server. We demonstrate through experiments how the algorithm establishes trust and quantify the overhead required to establish trust.