Abstract: To prevent an attacker from performing hop-by-hop traceback to locate source sensor nodes，this paper proposes a strategy called BFP.BFP uses some special messages to activate fake paths crossed with the shortest path.These fake paths may tempt the attacker in a direction farther from the shortest path to increase the attacker’s time to locate source node.In BFP，real messages are routed along the shortest path，thus promising least latency.Theoretical analysis and simulation study show that，comparing with CEM，BFP can enhance safety period by approximately 60% while maintaining equal energy overhead.

Key words: Wireless Sensor Network（WSN）, source-location privacy, fake paths, safety period

摘要： 为防止外部攻击者逐跳反向追踪源节点位置，提出分支假路径策略（BFP）。BFP利用特殊的数据包激发产生多条与最短路径相交的假路径。假路径引诱攻击者远离最短路径从而延长其定位源节点所需时间。策略在最短路径上传输数据包，保证最小信息延迟。模拟结果与理论分析表明，与CEM相比，BFP在耗能相等的情况下将安全时间提高约60%。

关键词: 无线传感器网络, 源位置保护, 假路径, 安全时间