monitoring tool for lan

[Pat Barber <mboceanside@xxxxxxxxxxxxxxxx>]

Can anybody recommend a tool that will help me
find a pc on a lan that is opening many(thousands)
of connections and is killing the cache of the
firewall.

This shuts all web connections down in the
dirt.

The firewall folks have been of little/no help
on what might be going on.

Apparently, an outside auditor brought a laptop
in the office around a week ago and our accounting folks
let him attach right into the lan with no questions.

This was the day the troubles began, but I thought we
were having either T1 line problems or firewall problems.

Everything now points to inside the LAN.

It might be one machine or it might be several.