Cisco UDLD: https://www.youtube.com/watch?v=OyHqeXY8P-g

I'm reverse engineering the protocol by looking at the packet capture. Please forgive me if something is wrong. I gave it my best shot to understand it. 


mac access-list extended UDLD_BLOCK
deny any host 0100.0ccc.cccc
permit any any
interface FastEthernet0/2
mac access-group UDLD_BLOCK in

derpy.network/cisco/udld.pcapng

https://dashiesparkle.deviantart.com/art/Vector-273-Coco-Pommel-2-563252760