Abstract: In mobile Ad hoc networks，because of the self-organize，dynamic topology and wireless surrounding of networks，routing security has become an important issue.This paper presents a secure multipath DSR routing protocol based on-demand protocol.The new protocol allows intermediate node reply to a route discovery packet that is different from others and solves security problems such as fabrication，modification，routing replay attack，black hole attack，DoS attack in mobile Ad hoc networks.And also alleviates routing rediscovery caused by evil nodes and selfish nodes or network environment changes.

Key words: routing security, Dynamic Source Routing（DSR）, multipath routing, intermediate node reply

摘要： Ad hoc网络的自组织、动态拓扑和无线接入等特点使得路由的安全问题日益突出。提出了一种在保证安全前提下允许中间节点返回路由应答报文的安全DSR路由协议。该协议对原有的信任机制进行了改进。仿真结果表明该协议可以有效防止路由信息伪装、篡改、路由重放以及黑洞攻击，可以缓解因恶意节点和自私节点拒绝网络服务或者网络环境变化造成的路由再发现问题。

关键词: 路由安全, 动态源路由协议, 多径路由, 中间节点返回路由应答