Guaranteeing bandwidth and minimizing delay in packet-switched (ATM) networks

Future high-speed networks that will support integrated video, voice and data applications are expected to utilize the concepts of ATM fast packet switching. The concepts of isolating misbehaving users and sharing resources to achieve optimal delay performance are extremely important to consider when designing queue service policies for practical implementations. Most previous service policies have been designed to satisfy one, but not both, of these goals. We present a novel service policy that combines the desirable features of isolation and sharing to provide guaranteed bandwidth for real-time traffic while attempting to minimize system delay. This service policy, guaranteed-bandwidth minimum-delay (GBMD), operates in two phases. The first phase of the policy ensures that the requested guaranteed bandwidth is delivered to each flow. The second phase, which only occurs when excess bandwidth is available, optimizes given performance criteria (e.g., system delay) by appropriately serving packets. The GBMD policy is easy to implement and flexible to tune based on system requirements. Simulation results show that overall system performance is superior to several other service policies.