Question : Good free way to check network traffic

I need a free program or a way to check network traffic to see if there are any breaks in the network or if any machines are causing too much traffic/collisions. Its on a Windows 2000/2003/XP network. Thanks.

Answer : Good free way to check network traffic

What are your switches? The best tool is MRTG, and its free, but it'll only work if your switches suport SNMP so that MRTG can query each port for traffic levels.

Otherwise, have a look at SmokePing. That'll run on one machine and keep a watch on how long it takes traffic to get to each other machine (that you tell it to watch) and builds up a log of response times.