Memory Complexity of Parsimonious Strategy in Automated Trust Negotiation

Abstract

Automated Trust Negotiation (ATN) has been proposed as a mechanism to establish mutual trust among strangers. While existing fundamental protocols and strategies are shown, this paper focuses on Parsimonious strategy. The most straightforward implementation of Parsimonious strategy has a very high memory consumption which may be problematic when it is used in real world environments. This paper proposes an implementation which keeps all requests in Disjunctive Normal Form (DNF) and further reduces its memory consumption by exploiting the history of the negotiation, while keeping the completeness of the strategy intact. In addition to that, proposed method provides a criterion to detect negotiation failures. Results obtained by means of simulations showed that the method proposed is effective in achieving its goals, without increasing the overall computational overhead. Theoretical analysis of the proposed method is also presented.