短波令牌环传输顺序优化

李程文 李迟生 林梦思 吴小晴

摘  要： 短波令牌环分布式自组织和无竞争机制有效避免了短波数据通信访问冲突问题，为短波通信提供良好的多址接入方式。针对短波令牌环中可能存在不必要中继节点产生的令牌开销影响网络吞吐量和时延等问题，转化为求解整个短波令牌环最优传输顺序表，提出Floyd和遗传算法联合算法对短波令牌环传输顺序进行优化。结果显示优化后的传输顺序表减少了不必要的中继次数，验证了算法优化短波令牌环传输顺序的有效性，并与单独使用Floyd算法或遗传算法进行对比，显示联合算法优化效果更好。通过分析表明，使用联合算法对短波令牌环传输顺序进行优化提升了网络吞吐量，减小了网络数据传输时延。

关键词： 短波令牌环; 短波通信; 中继减少; 传输顺序优化; 联合算法; 时延降低

中图分类号： TN915?34                        文献标识码： A                           文章编号： 1004?373X（2020）13?0011?05

Optimization of transmission order of shortwave token ring

LI Chengwen， LI Chisheng， LIN Mengsi， WU Xiaoqing

（School of Information Engineering， Nanchang University， Nanchang 330031， China）

Abstract： The shortwave token ring distributed self?organizing and non?competitive mechanism effectively avoids the shortwave data communication access conflict and provides a good multiple access mode for shortwave communication. For the problem that the possible token overhead generated by unnecessary relay nodes in the shortwave token ring may affect network throughput and delay， it is transformed into the optimal shortwave token ring optimal transmission sequence table， so a joint algorithm combining Floyd algorithm and genetic algorithm is proposed to optimize the shortwave order of the shortwave token ring. The results show that the optimized transmission sequence table reduces the number of unnecessary relays and verifies the effectiveness of the algorithm in optimizing the transmission order of the shortwave token ring. The result got by the joint algorithm is compared with those got by both Floyd algorithm and genetic algorithm. The comparative result indicates that the joint algorithm has better effect. The analysis conclusion shows that the shortwave token ring transmission order optimized by the joint algorithm can improve the network throughout and reduce the time delay of network data transmission.

Keywords： shortwave token ring; shortwave communication; relay cutting down; transmission order optimization; joint algorithm; delay reduction

0  引  言

短波令牌环协议[1]是實现多节点在同一广播信道中进行数据交互的MAC层协议，根据令牌数据对各个节点进行发送权利的控制，使得每个节点发送数据的机会公平且无冲突，避免了信道上的碰撞。同时，短波令牌环是一个自组织网络，拥有良好的自我修复能力，能有效解决单故障节点问题。将短波令牌环应用于短波通信中，有利于避免数据冲突，提供了较好的网络吞吐量和接入时延，强化了短波抗毁能力。

在节点数量多的情况下，短波令牌环由于网络拓扑变化可能产生不必要的中继，从而影响到整个网络的性能。……