TAS Scheduling With Grouping Flows

IEEE802.1Qbv (Time-aware Shaper: TAS) in IEEE802.1-Time-Sensitive Networking (TSN) has recently been applied within user networks for realizing factory automation and remote control. As mass customization matures, TAS is expected to extend its coverage to not only user networks but also wide-area networks to realize ultra-low-latency (ULL) communication between remote locations. TAS is TSN technology expected to be used for long-distance communications because it can guarantee maximum latency limits. However, designing a TAS schedule is an NP-hard problem, which becomes more difficult as the amount of delay guarantee flow increases. This paper proposes a method to reduce the computational complexity of TAS schedules for the problem that the computation time increases exponentially as the amount of scheduled traffic (ST) flows increases. This problem has serious impacts on TAS scheduling in wide-area networks. In the proposed method, flows with the same characteristics are grouped to reduce the number of flows to be input into the scheduling calculation. This suppresses computation infeasibility in the NP-hard problem and improves the schedulability of ST flows. This paper contributes to realizing TAS over wide-area networks, which are currently underutilized.