A full packet capturing, indexing, and database system
Open Source Monitoring System for performance and availability.
Just simple IP scanner in javascript
Nagios Open Source network monitoring software - The Standard In ITM
A Java based fault and performance management system
free netflow analyzer
Xplico is a Network Forensic Analysis Tool (NFAT)
Visual Network Management System
Real time monitoring : RPi-Monitor always keep an eye on your computer
Is your host up or down?
Web based management tool for unixes
Logs IP to IP contact, number of packets, bytes.