The development of hacker technology, especially the emergence of distributed denial of service assault has made distributed intrusion detection the emphasis of intrusion detection and even the whole network security field.

• 黑客技术的不断发展特别是分布式拒绝服务攻击（DDOS）的出现已经使分布式入侵检测（Distributed Intrusion detection, DID）逐渐成为入侵检测乃至整个网络安全领域的研究重点。