Hi,
if you are into the mac address monitoring I think the NAC profiler is made for you.
It can recognize hundreds of kind of devices from their behavior (DHCP, ARP, ...) and it classifies any device you plug on the network. You can even make custom rules if you have very specific products.
So you can determine "Cisco 9971 phones will go to this vlan" and any 9971 phone you bring in the future will be added in the NAC list.
It can also do this "monitoring" you are talking about, you can put any new mac address in a special category. And from there Profiler shows you its location and current behavior (what profiler thinks it is).
Nicolas
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