VLAN hopping is a type of network attack where an attacker who is connected to an access port (which is attached to a particular VLAN) can gain access to network traffic from other VLANs.
Normally, a computer attached to a switch access port (which is attached to a particular VLAN) can get traffic only from the VLAN related with that switch port.
Using VLAN hopping attack, an attacker can sniff network traffic from another VLAN
using a sniffer (protocol analyzer) or send traffic from one VLAN
to another VLAN.
There are two types of VLAN hopping attacks. They are Switch Spoofing attack and Double Tagging attack.
Click the following links to learn
• What is Switch spoofing attack and how to prevent switch spoofing attack
• What is Double tagging attack and how to prevent double tagging attack