The Network UPS Tools repository
Performance Co-Pilot
High performance ping tool
A Swiss army knife for your daily Linux network plumbing
Ncurses-based monitoring application for wireless network devices
SQL operating system instrumentation and monitoring framework
Nagios Open Source network monitoring software - The Standard In ITM
Open Source Monitoring System for performance and availability.
VoIP SIP and SKINNY quality analyzer and packet / audio recording tool
Powerful, open-source network protocol analyzer
ICMP-based network bandwidth measurement tool
Firewall log analyzer
Intelligently block brute-force attacks by aggregating system logs
Manage and interpret IPMI systems with common a software tool
Network Load Balancer and Application Security
Next Generation Open Source Firewall
High capacity syslog data collection, filtering, and management.