Profit-maximizing trustworthiness levels of composite systems

Service providers face the ever-increasing problem of meeting customer expectations while maximizing profits. This optimal balance is very important for delivering better service quality to users and keeping costs under control through efficient resource allocation. In this paper we suggest optimal strategies for managing system trustworthiness in two different contexts. In the first one the provider has limited information about the users' trustworthiness preferences, which have to be satisfied on every transaction. In the second context, the provider knows what the effect of possible outcomes on customer's trust level and, given that the customer will perform a certain number of transactions, would like to know whether the system trustworthiness should be managed at any point in time in order to meet customer's expectations in a cost-effective way. The optimality of the proposed strategies is demonstrated via both analytical techniques and simulations.