Improving Bandwidth Utilization Based on Deterministic Delay Bound in Connection-Oriented Networks

Packet scheduling disciplines play an important role in providing Quality of Service (QoS) guarantees to applications traffic in high speed networks. Several scheduling disciplines have emerged in the literature that are capable of providing guarantees on various QoS parameters, such as packet delay, jitter, loss and throughput, while maintaining fairness among various connections. However, there is a trade-off between the performance and the simplicity of operation and implementation performance of the scheduling schemes. Thus the First-Come-First-Serve (FCFS) scheduling discipline has remained popular due to its overriding simplicity in spite of its poor capabilities in providing QoS guarantees. In previous work it has been shown that a practical worst case bound can be obtained for a deterministic delay guarantee in networks using the FCFS discipline, by imposing a source rate condition on each connection, that restricts the overall network utilization. In this paper, a modified source rate condition is proposed that can significantly increase the bandwidth utilization, while still maintaining the deterministic delay guarantee.