Real-Time traffic monitor?

[Eric F Crist]

Hey all,

I've got a fairly heavy-duty machine doing firewalling for my  
network, and the VAST majority of it's processing power is going  
unused.  As such, I'd like to put X on this box, attach a monitor,  
and display a series of real-time traffic graphs.  Does anyone know  
what the best software to use for this would be?

Thanks!

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Eric F Crist
Secure Computing Networks