Multi-rate combination of partial information-based routing and adaptive modulation and coding for space deterministic delay/disruption tolerant networks

Delay/disruption tolerant network (DTN), in which the network connectivity is intermittent and the node buffer size is limited, is a promising approach to model space networks. In this study, the authors focus on the space deterministic DTNs whose mobility and connectivity are predictable. A rate adaptation scheme based on adaptive modulation and coding (AMC) is adopted. Based on the analysis of data delay in DTN, the authors propose two routing algorithms, namely local information-based routing (LIR) and local and neighbour information-based routing (LNIR) for space DTNs. Queuing information in partial nodes is used in routing selection. The two proposed algorithms outperform the traditional least delay routing (LDR) in average end-to-end delay, packet loss ratio and traffic distribution. With the same network load, the average delay of LDR, LIR and LNIR are 44.43 s, 22.82 s and 14.08 s while the packet loss ratio of three algorithms are 6.37, 0.76 and 0.00%. Simulation result also shows the superiority of AMC over fixed modulation and coding (FMC) in space DTNs. When the DTN is heavily loaded, the delay of AMC is 15 s smaller than that of FMC. At the same time, the packet loss ratio of AMC is one-sixth that of FMC.