Fault-Tolerant Dynamic Scheduling and Routing for TSN based In-vehicle Networks

Functional safety is considered as one of the utmost requirements of the future autonomous vehicle, which consumes an ample amount of safety-critical data exchange among sensors, actuators and controllers through the in-vehicle network (IVN). IVN should provide enough guarantees to satisfy the high-reliability requirement of such autonomous vehicle applications. To avoid packet failures, Time-sensitive Network (TSN) proposes a fault-tolerant mechanism called frame replication and elimination for reliability (FRER) in IEEE 802.1CB standard. The main idea of FRER is to transmit safety-critical data via multiple disjoint paths between source and destination so that if one path fails to transmit the safety-critical data, the other path can still deliver the packet to its destination. In this paper, four different dynamic scheduling and routing heuristics are analyzed to support FRER functionality in TSN based IVN. These heuristics use combined score value, each score value is dedicated for a single path, as a measure to schedule and route incoming flow in multiple redundant paths on the fly. One of the algorithms, the Fault-Tolerant Bottleneck Heuristic (FTBH) outperforms others in terms of schedulability and response time. It schedules around 3.0–7.0% more flows as compared to other developed heuristics depending on the network load.