graphical tool to check bandwidth usage

[Barry Brimer]

>> Hi all,
>> I have been asked for a graphical tool to check the the bandwith usage that
>> pass through my RHEL 5 firewall.
>>
>> First I thought in the fantastic wireshark (a.k.a ethreal) but I don´t know
>> how to see in real time and in a graphical way the usage of the bandwidth
>> usage from the hosts from my local lan. This way I can see quickly if a
>> host
>> is abusing.
>>
>> If it´s not possible, it´s time to explore another solution, Do you know
>> one
>> with gives me this possibility?

I would look at ntop <http://www.ntop.org/> or HowNetWorks 
<http://hownetworks.python-hosting.com/>