Provisioning virtual private networks in the hose model with delay requirements

Virtual private networks (VPN) provide a cost-effective means of meeting the communication needs among several sites. The hose model for VPN configuration alleviates the scalability problem of the pipe model by reserving bandwidth for traffic aggregates instead of between every pair of endpoints. Existing studies on quality of service (QoS) guarantees in the hose model deal only with bandwidth requirements. In this paper we enhance the hose model to specify delay requirements between endpoints. Three categories of algorithms, namely the pipe mesh, the multiple source-based trees, and the shared tree approaches, are then proposed for VPN provisioning. We investigate methods of implementing the shared tree approach to meet the delay requirements with low provisioning cost and small computation overhead.