Ants-Based On-Demand Routing Algorithm for Mobile Ad Hoc Networks

An ants-based on-demand routing algorithm （AORA） specialized for mobile ad hoc networks is proposed. AORA measures the network＇s traffic information including delivery time, route energy etc. by the continuous delivery of data packets, then calculates the compositive parameter for each route which can be seen as the stigmity and uses it to choose the comparatively optimal route in real time. To adjust the weight of each traffic information, the algorithm can meet the different demand of the network＇s user. Multipath source self repair routing （MSSRR） algorithm and dynamic source routing （DSR） can be seen as the special samples of AORA. The routing overhead is not increased in this algorithm. By using simulation, it can be seen that the performance of AORA is better than that of DSR in all scenarios obviously, especially the delivery fraction is increased by more than 100 96.     

移动自组网按需机制路由协议路径失效预测和局部修复算法

提出利用信号强度对将要断开的链路进行检测，并在局部利用路径请求—路径回答过程，找到替代路径，对原来的路径进行局部修复的算法。在尽量少增加路由开销的同时，达到提高路径修复的效果。同时对缓存器中路径设置失效时限，以免长时间未用路径时误用失效路径。在DSR协议上应用改进算法，在ns-2仿真环境中对6组不同场景进行仿真，验证算法正确，明显提高了移动自组网的性能。     

移动自组网路由协议DSR性能评价

研究移动自组网的难点之一是开发能够跟随网络拓扑变化，在移动节点之间快速找到有效路径的路由协议。DSR协议作为一种简洁有效的按需机制路由协议，成为IETF的MANET工作组提出的草案之一。本文利用MANET工作小组推荐的Ns2仿真软件对DSR进行模拟，从源节点个数、分组发送频率、移动速度、节点密度、节点个数五个方面分析DSR的性能，指出对DSR性能影响最大的因素。分析随分组频率降低协议性能下降是由于它的路径缓存策略引起，提出将针对DSR路径缓存，搜索，抛弃策略进行改进。