FRUDP: A Reliable Data Transport Protocol for Aeronautical Ad Hoc Networks

In this paper, we cope with the reliable and efficient data transfer problem in aeronautical ad hoc networks (AANETs). AANETs are different from terrestrial ad hoc networks and these distinctions feature AANETs with large propagation delay, highly dynamic network topology, and high error probability, which pose many new challenges for data transfer in such environments. In this paper, we propose a protocol, called FRUDP, which combines reliable UDP and fountain code to achieve reliable and efficient data transfer in AANETs. It employs Raptor codes to recover from data losses to mitigate retransmission caused by high channel losses in AANETs. A code rate determining algorithm is developed to estimate the redundancy on the fly by taking into full consideration the time-varying aeronautical network conditions. Moreover, the improved selective negative acknowledgment scheme is utilized to solve the bandwidth asymmetry problem in AANETs and a congestion control scheme is deployed to decouple congestion decisions from packet losses in order to avoid the erroneous congestion decisions due to frequent link handoffs. The proposed FRUDP is fully implemented directly on top of UDP in Linux and examined over a variety of emulation network environments. The experimental results show that FRUDP is suitable for reliable and efficient data transfer service in AANETs.