Fair Assured Services Without Any Special Support at the Core

Many users require IP networks with the capacity to guarantee a minimum throughput even during periods of congestion. Furthermore, it is also desirable to share the excess unsubscribed bandwidth among active users if aggregate demand does not exceed network capacity. This kind of service, named assured service, can be provided through the Assured Forwarding (AF) Per Hop Behavior (PHB) defined in the DiffServ architecture. DiffServ mechanisms require special networking support at both the edge and the core nodes to guarantee the differentiated service. In this paper we propose the Ping Trunking scheme as a suitable mechanism to provide assured services to network users without the need for modifying core nodes. Ping Trunking is an edge-to-edge management technique that completely addresses the regulation of aggregate traffic streams at the edge of the network. In addition, it also overcomes some unfairness issues found in AF when sharing the available bandwidth among heterogeneous aggregates. Simulation results have validated the effectiveness of our proposal.