Traffic Monitor

[Spidey Knepscheld]

Hi

I am an ISP running FreeBSD as a firewall and as a Mail Server. My problem
is that I am not able to monitor the amount of traffic that user are using
on my network. in south Africa bandwidth is extremely expensive and I need
to take my bandwidth to the edge.

My network looks like this: My Link comes in on a Cisco 805 from the router
it goes to the first NIC on the Firewall from the second NIC it runs into a
10base HUB where there are only 3 ports used one as I said for the Firewall
the other for a FreeBSD box (I want to use this box for traffic monitoring)
and then one port for the rest of the network which connects to a 100base
switch. The reason I used the 10base HUB is because it broadcasts all the
data to all the ports. So for all data to and from the firewall will be
caught by the Monitoring BSD box. I hope this makes sense.

What I am looking for is some app that could show me live what ip on my
network is utilizing what part of the bandwidth. Don't laugh !!I have a 256k
Diginet connection and I would like to see who is killing my network. I do
get live graphs from my upstream supplier but it shows the line utilization
from my router and not who is using what.

So I can't be proactive in solving speed issues I need to wait for it to
happen and then by a process of elimination disconnect segments of the
network and see when the graph drops. I tried TCPDUMP but it is difficult to
understand (perhaps I am just stupid) but it's a time consuming process and
to late to fix the problem.

I hope this makes sense to someone

thank you

Spidey