Contact Quality Aware Routing for Satellite-Terrestrial Delay Tolerant Network

In space delay tolerant network (DTN), the absence of adequate nodes makes the communication opportunities precious. If the messages are transmitted using a path which exists high bit error, it can increase the delivery delay and reduce the delivery ratio. Therefore, how to distinguish the contact quality and select a path with little bit error is crucial to improve the network performance. In this paper, we propose a contact quality aware routing which operates cooperatively with Licklider Transmission Protocol (LTP). We use the processing signals in LTP to reflect the contact quality. Further more, we propose a contact quality based forwarding scheme to select a path which exists little bit error. The enhancements are verified using a test-bed with 15 simulation nodes. The experiments show that the proposed schemes can reduce the delivery delay, increase the delivery ratio and improve the throughput.