VLAN Trunking (802.1Q) allows physical network interfaces in a computing environment to be shared, or multi-homed. As data centres get more complex and the number of interconnected services increases, it's becoming more complex and expensive to provide dedicated cabling and network switch ports to allow for all the required connections. VLAN trunking allows for multiple virtual network connections to be maintained on a small number of physical adapters. Each Virtual Local Area Network (VLAN) gets a unique VLAN tag, and each packet on the network gets branded with the tag for the VLAN it’s associated with. Network devices on the network then only interact with packets that have the correct tags. This allows multiple different logical networks to run on the same cable and switch infrastructure.