The Ethernet standard has a provision to combine multiple broadcast domains, and thus IP subnets, onto a single Ethernet cable using a Virtual LAN (IEEE 802.1Q VLAN) configuration. To use VLANs, both ends of the Ethernet link must be configured to support the defined VLANs. The benefits include a logical division of workload, enforcing security isolation, and splitting traffic across several manageable broadcast domains. VLANs allow traffic separation from the 10 GbE switch to compute nodes. By design, Ethernet traffic on one VLAN cannot be seen by any host on a different VLAN. To enable communication between two VLANs, you should use an external router.
Note:
You can create more than one VLAN per Ethernet connection.
For a general introduction to VNICs, see Introduction to Virtual NICs (VNICs).