VoIP SIP and SKINNY quality analyzer and packet / audio recording tool
Community-based GPL-licensed network monitoring system
Light-weight system monitor for X
An eye on your system
An engine to make Tor network your default gateway
ICMP-based network bandwidth measurement tool
basic networking tools
Nagios Open Source network monitoring software - The Standard In ITM
Pure Java Network Tools
Xymon monitors your hosts, your network services, and everything else.
Proxy Cache and Web filtering Appliance
Enterprise-class, distributed monitoring solution for networks & apps
Monitorix is a system monitoring tool
Continuously monitor server connections
Database monitoring agent for zabbix
Pinger alert, STATICTICAL TABLES, send EMAILs or SMS by SMS GATEWAY
Open source tool to monitor your servers and websites
track log files, block intrusions, and much more