My network for packet collisons? I have a network consisting of 5 sites/100 computers. Each site is connected with routers, and we are using hubs at the main site. Ameritech/SBC just finsihed upgrading us to a full T1 network, and they noticed some packet collisions. They told me to monitor this, and find out what the problem is. I think the hubs at the main location are going to need to be upgraded to switches, but I need to verify this. Can anyone suggest a program to use to monitor the network for packet collisons, and that shows me what segment is causing it?? Your help is appreciated.