Curbing aggregate member flow burstiness to bound end-to-end delay in networks of TDMA crossbar real-time switches

Abstract

To integrate the nowadays rapidly expanding distributed real-time systems, we need multi-hop real-time switched networks. A (if not "the") widely recognized/adopted real-time switch architecture is the TDMA crossbar real-time (TCRT) switch architecture. However, the original TCRT switch architecture assumes per-flow queueing. To support scalability, however, queue sharing (i.e. flow aggregation), must be allowed. With simple flow aggregation, flow burstiness can grow and infect, making schedulability and end-to-end delay bound analysis an open problem. To deal with this, we propose the real-time aggregate scheme. The scheme complies with the existing TCRT switch architecture, and deploys spatial-temporal isolation and over-provisioning to curb aggregate member flows' burstiness. This allows us to derive the closed-form end-to-end delay bound, and give the corresponding resource planning and admission control strategies. Simulations are carried out to show the effectiveness of the design.