Due to the constantly changing sea surface, there is a high risk of link fragility caused by sea waves when different marine users are intended to establish stable links for communication. To ensure stability with less delay, finding a stable route is one of the crucial aspects of maritime networks. In order to achieve this aim, we propose a routing protocol for cognitive maritime networks based on software-defined networking (SDN). This SDN-based cognitive routing protocol provides stable routes among different marine users. To provide the global view of the whole network, a main controller is placed close to the seashore, whereas the localized views are provided by the cluster heads. Autonomous surface vehicles are used as gateways under sparse network conditions to collect and transport data among clusters, and to and from the main controller. This is an SDN-based ship-to-ship communication scheme where two ships can only establish a link when they not only have consensus about a common idle channel but are also within the communication range of each other. We perform extensive simulations to test the proposed scheme with different parameters and find better performance in comparison with both SDN-based and non-SDN-based schemes in terms of end-to-end delay, packet delivery ratio, and routing overhead ratio.

中文翻译：

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软件定义海事网络中的认知路由

由于不断变化的海面，当不同的海洋用户打算建立稳定的通信链路时，由海浪引起的链路脆弱性的风险很高。为了确保减少延迟的稳定性，找到稳定的路线是海事网络的关键方面之一。为了实现此目标，我们提出了一种基于软件定义网络（SDN）的认知海事网络路由协议。这种基于SDN的认知路由协议可在不同的海洋用户之间提供稳定的路由。为了提供整个网络的全局视图，将主控制器放置在靠近海边的位置，而局部视图则由群集头提供。自主地面车辆在稀疏网络条件下用作网关，以在群集之间以及往返于主控制器之间收集和传输数据。这是基于SDN的船对船通信方案，其中，只有两艘船不仅在关于公共空闲信道的共识上而且在彼此的通信范围内，才能建立链接。我们进行了广泛的仿真，以测试使用不同参数的提议方案，并在基于端到端的延迟，数据包传递率和路由开销率方面，与基于SDN的方案和基于非SDN的方案相比，都发现了更好的性能。