一种低开销自适应SD­­­－UANET流表下发机制

软件定义无人机自组网场景下，相较于软件定义有线网络，其网内节点数量更多导致各节点流表数量爆发式增长。针对原OpenFlow v1.5协议中主动下发流表的机制与flow_mod消息结构对于无线环境与多跳流表下发的不兼容，导致无人机自组网场景下流表下发开销过大以及收包率降低。对于无人机自组网场景下OpenFlow v1.5协议中的问题，通过组播切包组包去尾策略与流表源、目的地址自适应压缩策略，减少了头部开销，提升了无线资源利用率，并减少了冗余的流表项部分，在保证功能不缩减的情况下较显著地减少了开销。OPENET 14.5仿真验证显示，此机制大幅减少了网络控制开销，提高了网络吞吐量，降低了端到端时延与丢包率。

A software-defined low overhead adaptive flow table issuing mechanism for unmanned aerial vehicle ad hoc network

In the scenario of software defined unmanned aerial vehicle(UAV) ad hoc network,compared with the software defined wired network,the number of nodes in the network is more,leading to an explosion in the number of flow tables of each node.The incompatibility between the mechanism of issuing flow tables actively in the original OpenFlow V1.5 protocol and the flow_mod message structure for the wireless environment and issuing under multi-hop flow tables causes that the sending cost under the downflow table of UAV ad hoc network scene is too large and the receiving rate is reduced.For the problems in OpenFlow V1.5 protocol in the UAV ad hoc network scenario,the strategy of packet cutting and group de-trailing and the adaptive compression strategy of flow table source and destination can reduce the head overhead,improve the utilization rate of wireless resources,and reduce the redundant flow table items,which significantly reduce the overhead without reducing the function.The simulation results of OPENET 14.5 show that this mechanism greatly reduces network control overhead,improves network throughput,and reduces end-to-end delay and packet loss rate.