Tools for Monitoring Network Performance

Multi Router Traffic Grapher (MRTG)

http://oss.oetiker.ch/mrtg
This is a tool to monitor devices (routers, switches, servers, networks).

What it does
You have a router, you want to know what it does all day long? Then MRTG is for you. It will monitor SNMP network devices and draw pretty pictures showing how much traffic has passed through each interface.
Routers are only the beginning. MRTG is being used to graph all sorts of network devices as well as everything else from weather data to vending machines.
MRTG is written in perl and works on Unix/Linux as well as Windows and even Netware systems. MRTG is free software licensed under the Gnu GPL.

Smokeping

http://oss.oetiker.ch/smokeping

SmokePing keeps track of your network latency:

• Best of breed latency visualisation.
• Interactive graph explorer.
• Wide range of latency measurment plugins.
• Master/Slave System for distributed measurement.
• Highly configurable alerting system.
• Live Latency Charts with the most 'interesting' graphs.
• Free and OpenSource Software written in Perl written by Tobi Oetiker, the creator of MRTG and RRDtool

Cacti

http://www.cacti.net




Cacti is a complete network graphing solution designed to harness the power of RRDTool's data storage and graphing functionality. Cacti provides a fast poller, advanced graph templating, multiple data acquisition methods, and user management features out of the box. All of this is wrapped in an intuitive, easy to use interface that makes sense for LAN-sized installations up to complex networks with hundreds of devices.