Residual Slot Availability–Driven Joint Routing and Scheduling Framework for Time-Sensitive Networks
Time-sensitive networking (TSN) has emerged as a foundational technology to ensure deterministic communication in industrial automation, automotive, and avionics systems. A persistent challenge in TSN is the joint planning of routing and scheduling for time-triggered (TT) flows, where sequential time-slot reservations often lead to fragmentation, dispersing residual bandwidth and limiting subsequent flow allocations. This fragmentation effect, despite its significant impact on network performance, has received limited attention. To address this issue, we first develop a fragmentation-aware metric that quantifies the availability of residual time slots through integer partitioning. Then, a similarity model integrating source–destination and period similarity features is introduced to aggregate compatible TT flows along common routes, thereby improving bandwidth utilization. Finally, we propose a joint planning method for routing and scheduling (JPMRS) grounded in integer splitting theory. Simulation results demonstrate that JPMRS substantially improves TT flow scheduling success rate, reduces best-effort (BE) latency, and enhances overall system efficiency in TSN environments.