Motivation

A personal environment in the future is expected to involve applications that will demand high levels of security in network communication. To ensure reasonable levels of privacy and authentication, applications rely on encryption. Algorithms for encryption are varied in their characteristics, mainly on account of the exact concerns addressed by the algorithm designer. This naturally leads to a whole range of values that different algorithms could produce in terms of desired performance metrics such as level of security, speed of execution and so on. This may force an application developer, who is characterized by a lack of specific/theoretic knowledge about encryption strategies, to use sophisticated ``knobs'' that allow him to choose from a range of options for better performance. These knobs in turn, complicate the implementation of protocols, interfaces to these protocols and ways to reason about the correctness of these protocols.

In a c0pe environment, the relative importance of some of the performance metrics mentioned previously differ from that of a traditional network environment. In fact, the performance metrics may even be different, and some issues like battery life become very critical. Hence, considering these new metrics, we need to study whether the knobs as described earlier should continue to be used or not needed at all.

If universal encryption, i.e all network communication being encrypted, is possible at negligible costs, then the use of such current knobs would be rendered unnecessary. Otherwise, even if strong encryption is possible only for a class of applications and environment, there is a compulsive need to precisely characterize them to provide an application developer with a quick reference to reason about the use of the knobs for his purposes. Hence a study that analyses the feasibility and costs of universal encryption is essential.