Abstract:
Time-triggered Ethernet (TTE) is a new high-speed, real-time and fault-tolerant communications technology that combines high real-time services and traditional best-effort services. TTE is highly valuable in the application of transmission technology in the aerospace field. To ensure the security requirements of important information, the TTE network adopts a dual redundant network structure. Traditional links execute switching operation at the occurrence of failure, and the physical link switching causes some overhead and delays. When using dual-network transmission, the protocol is complicated, and the discard windows discard redundant packets, which will also cause the increase of network delay. In this paper, an adaptive dual redundant network structure was proposed.This structure did not only meet the real-time performance requirements of the TTE network services, but also met the security requirements of the TTE network service. Time labels for redundant messages were designed in this structure, and using time labels could restore transmissions adaptively. A scheduling scheme of mixed traffic—time-triggered (TT) traffic, rate-constrained (RC) traffic, and best-effort (BE) traffic—in TTE network was designed. Based on the importance of the packet, the sender adaptively classified the network packet. Among the mixed traffic scheduling transmission, the TT traffic through the terminal redundancy was processed and backed ups, and it was transmitted in dual networks. RC and BE traffics were not important information; therefore, they did not need backup; they were transmitted dispersedly in dual networks. In addition, based on deterministic network analysis method, the closed delay bound of RC traffic under adaptive double redundant scheduling method was deduced. Furthermore, several simulation result under extreme network, determined network, and queuing theory simulation model show that the scheduling method based on adaptive dual redundancy can reduce the network delay. This design does not only satisfy the security requirements of the TTE network, but also meets the real-time requirements of the service.