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Block L2 Hubs

Hello All,


I have a need to block users from connecting L2 hubs into my network, I am using Cisco L3 3850.

Is it more effective to use stp port fast or pbdu ?




Hub  is physical layer device

To deny users to connect hub to your switch port, the best and simplest way is port-security feature. 

Portfast is not related to your problem.

BPDU guard is good but if they disable STP on their hub, it becomes useless.



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To expand a bit on Houtan's suggestion, if your restrict your edge ports to only allowing one MAC, it will negate the advantage of connecting a "simple" hub or switch to the port.  However, if the connected device supports NAT, then you might restrict the edge port to a single known MAC (which will negate lots of NAT devices, but not if it supports setting its MAC).