Agent-Based VPN Architecture: A Framework and the Optimal User Connectivity Problem (Static Case)

Remote access VPN services have gained significant popularity. In this paper, we present the basic framework of an agent-based VPN architecture (ABVA) in which organizations do not need to maintain VPN servers. We then consider the problem of the user connectivity decision in an ABVA, which consists of the selection of the best rendezvous point (RP) for each user in a heterogeneous access environment. Specifically, we consider the optimal user connectivity problem from the perspective of an ABVA provider. For the static case of known users, we present an optimization formulation. An advantage of our formulation is that it can incorporate users with heterogeneous access technology, along with delay and penalty factors. Through our computational study, we observe that the delay factor is not necessarily dominant in all cases, while the bandwidth access requirement plays a critical factor in an overloaded situation. Finally, we briefly comment on how the results from the static case are useful with regard to the random arrival case.