filtering ARP and detecting ARP spoofing

[falcifer <falcifer2001 () yahoo es>]

Hi
I've 2 questions:

1- Are there any way to filter ARP packets on Linux (I've heard about
arptables but I wasn't able to find how can I use it)

2-In a environmet with a dynamics IPs, how can implement a IDS to detect
arp spoofing? what rules could I implement for it? are any Cisco switch
that implement any of these features?

Thanks at all
-- 
falcifer <falcifer2001 () yahoo es>


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