SAT01-2: Service Differentiation by a Link Layer Protocol Based on SR ARQ over a Satellite Channel

This paper studies the case where multiple IP flows are aggregated over a single satellite channel and an error recovery by retransmissions is performed by Selective- Repeat (SR) ARQ. We propose MQ-PFRS (Multi-QoS Per-Flow Resequencing) ARQ that provides a differentiated service for an IP flow depending on its traffic class, such as real-time traffic (ex. UDP) or non-real-time traffic (ex. TCP). MQ-PFRS ARQ eliminates interferences among IP flows by resequencing received packets independently for each IP flow. It also controls the maximum packet delay by limiting the persistency of retransmissions and the maximum resequencing time for each packet. This paper also presents the analysis of the probability distribution of real-time packet delays. Simulation results show that the delay variation of real-time traffic is effectively controlled by proposed MQ-PFRS ARQ and the results of the analysis well capture the characteristics of the packet delay distribution. This means that MQ-PFRS is effective for handling multiple classes of IP flows and quality of real-time traffic transferred by the scheme can be predicted by the analysis.