一种基于仿生学的MANET拥塞节点自适应回避路由协议

A Bio-Inspired Adaptive MANET Routing to Circumvent Congestion Nodes

针对MANET中出现的因节点拥塞而导致路由不稳定、频繁重路由等问题,本文借鉴大肠杆菌培育过程中对营养液浓度变化的新陈代谢自适应调节行为和其数学描述模型ARAS,提出了一种新的拥塞节点自适应回避的MANET路由协议ATAR,其主要思路是:将节点缓存队列信息(可反映该节点拥塞程度)和目的端反馈包跳数信息(可反映该节点到目的端的路径长短)归一化处理后定义为节点的适应值,并将其映射为菌体的成长速率;再在随机性上修正了原始描述模型ARAS,并用其分别计算该节点的所有邻节点若被当作它到目的端路由的下一跳节点时,它们各自对该路由性能的改善度,然后选择其中改善度最大的邻节点作为其下一跳节点,以自适应避开拥塞的邻节点,同时选择较短路径.仿真结果比较显示:ATAR突发大时延发生概率明显较小,具有更低的数据包平均端到端延迟,数据分组投递率也得到提高,体现出ATAR拥塞避免的策略优势较大,并且还观察到ATAR负载均衡程度也优于AODV,瓶颈节点承担的负载差异较AODV小54%.

Traditional Ad Hoc network routing protocols are mainly based on the condition ＂Shortest Path＂,and possibly form many congestion nodes to cause routing instability and re-routing.To this point,this paper proposed a new bio-inspired adaptive routing protocol（ATAR） based on a mathematic model ARAS which is originally a model for its host Escherichia coli cells to adapt to changes in the availability of a nutrient.In this paper,queue buffer of routing node and hop count of feedback are defined as a new metric,fitness,which represents the comprehensive factor of congestion level and the length of routing path.We map the fitness of neighbors of routing node to the cell volume growth speed in the improved ARAS model,and calculate the state values of neighbors with the model.Then,the routing node selects the next hop according to the maximum.Using this method,we can adaptive to choose a leisurely node as the next hop with shorter path.