VLAN hopping

VLAN hopping is a computer security exploit, a method of attacking networked resources on a Virtual LAN (VLAN). The basic concept behind all VLAN hopping attacks is for an attacking host on a VLAN to gain access to traffic on other VLANs that would normally not be accessible. There are two primary methods of VLAN hopping: switch spoofing and double tagging. Both attack vectors can be easily mitigated with proper switchport configuration.