摘要： 提出了一种利用被动监听Overlay 网络进行 DDoS 攻击源追踪的新方法。它能够跨越多个自治系统追踪一个大规模DDoS 攻击的多个攻击源。基于该方案，设计和实现了一个IP 源回溯系统：SnifferTrack。描述了它的体系结构和组成、追踪过程和算法。最后，提出了SnifferTrack 系统中的几个局限以及进一步的工作。

关键词: 计算机网络安全；分布式拒绝服务攻击；IP 源回溯

Abstract: A new approach to tracing sources of DDoS attacks based on passive sniffing overlay network (PSON) is proposed, which can span multiple autonomy systems to trace back to multiple attack sources of a large scale DDoS attack. Based on this solution, it designs and implements an IP traceback system: SnifferTrack. The architecture and composition of the system are described, as well as the tracing process and algorithms.Several limitations of the system and future work are also proposed.

Key words: Computer network security; DDoS attack; IP traceback