Virtual private network provisioning in the hose model

Abstract

A virtual private network (VPN) provides private network connections over a publicly accessible shared network. Provisioning quality of service and flexibility, but also saving cost through link multiplexing are some of the main goals when identifying suitable models for VPNs. A very promising approach to achieve these goals is given by the hose model introduced four years ago. In this report, we focus on the different possible variants of this model and provide ideas, implementations, and simulation results for many aspects. We formulate and solve the problem of building VPN hoses as well as validating them. To do this, we distinguish between different routing approaches. Previous to this report, many tree routing issues were discussed. We add algorithms and linear programming formulations for unsplittable and splittable routing; for the latter, our algorithm runs in polynomial time. Finally, we compare performance issues of different hose routings and put the hose model in contrast to a more traditional approach of setting up a directly linked VPN.