Set up a virtual local area network
A virtual local area network (VLAN) is a method of creating independent virtual networks within a physical network. Using a VLAN can help you with network administration by allowing you to separate segments of the LAN (like departments of a company) that shouldn’t exchange data using the LAN.
A VLAN is made up of computers that behave as if they were connected to the same network, even though they may be connected to different physical networks. Network administrators can manage VLANs using software instead of hardware.
You can set up a VLAN service using Network preferences.
Choose Apple menu > System Preferences, then click Network.
Click the Action pop-up menu at the bottom of the list on the left, then choose Manage Virtual Interfaces.
Click the Add button , then choose New VLAN.
Give the service a name, then enter a value in the Tag field.
Click the Interface pop-up menu, choose a network interface, click Create, then click Done.
Select the VLAN in the list, click Advanced, then enter settings for the service, such as IP settings, the DNS server address, search domains, proxy or WINS server settings, or TCP/IP settings.