OSSEC is an Open Source Host-based Intrusion Detection System that performs log analysis, file integrity checking, policy monitoring, rootkit detection, real-time alerting and active response.

A GPL RDP proxy

Falcon是一款基于inotify-tools 开发的Web服务器文件监控平台 能够实时监控Web目录文件变化(新增，修改，删除)，判断文件内容是否包含恶意代码，自动隔离常见Webshell，保证Web目录文件安全

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine developed by the OISF and the Suricata community.