Improving Secure Communication Policy Agreements by Building Coalitions

In collaborative applications, participants agree on certain level of secure communication based on communication policy specifications. Given secure communication policy specifications of various group members at design time, the minimum set of resources for a pair, called resolved policy level agreement (RPLA) is translated into appropriate security service implementations, for the pair-wise communication to take place. We propose a novel idea that the members may extend pair-wise communication quality through other trusted nodes whose communication resources offer more security. We propose a heuristic algorithm which finds the best quality of protection (QoP), a measure of the resistance to an attack, path through coalition of trusted nodes. The results from our experiments indicate a significant improvement in QoP in the range of 13% to 48% over pair-wise communications.