Resource Optimization to Provision a Virtual Private Network Using the Hose Model

Virtual private networks (VPN) provide a secure and reliable communication between customer sites over a shared network. With increase in number and size of VPNs, providers need efficient provisioning techniques that adapt to customer demands. The recently proposed hose model for VPN alleviates the scalability problem of the pipe model by reserving for its aggregate ingress and egress bandwidth instead of between every pair of VPN endpoints. Existing studies on quality of service guarantees in the hose model either deal only with bandwidth requirements or regard the delay requirement as the main objective ignoring the bandwidth cost. In this work we propose a new approach to enhance the hose model to guarantee delay requirements between endpoints while optimizing the provisioning bandwidth cost. We connect VPN endpoints using a tree structure and our algorithm attempts to optimize the total bandwidth reserved on edges of the VPN tree. Our proposed approach takes into account the user preferences in meeting the delay requirements and provisioning cost to find the optimal solution of resource allocation problem. Our experimental results indicate that the VPN trees constructed by our proposed algorithm meet minimum delay requirements while reducing the bandwidth requirements as compared to previously proposed algorithms.