Dell N3200-ON Networking N-Series Switches CLI Reference Guide version 6.8.0 - Page 879

VLAN Commands Dell Networking N1108EP-ON/N1500/N2200-ON/N3200-ON Series Switches Dell Networking 802.1Q VLANs are an implementation of the Virtual Local Area Network, specification 802.1Q. Operating at Layer 2 of the OSI model, the VLAN is a means of parsing a single network into logical user groups or organizations as if they physically resided on a dedicated LAN segment of their own. In reality, this virtually defined community may have individual members scattered across a large, extended LAN. The VLAN identifier is part of the 802.1Q tag, which is added to an Ethernet frame by an Q-compliant switch or router. Devices recognizing 802.1Q-tagged frames maintain appropriate tables to track VLANs. The first three bits of the 802.1Q tag are used by 802.1p to establish priority for the packet. Dell Networking switches supports 802.1Q VLANs. As such, ports may simultaneously belong to multiple VLANs. VLANs allow a network to be logically segmented without regard to the physical locations of devices in the network. Dell Networking switches supports up to 4093 VLANs for forwarding. Interfaces can be configured in trunk mode (multiple VLAN support) or access mode (single VLAN support). VLANs can be allocated by subnet and netmask pairs, thus allowing overlapping subnets. For example, subnet 10.10.128.0 with Mask 255.255.128.0 and subnet 10.10.0.0 with Mask 255.255.0.0 can have different VLAN associations. Access, trunk and general mode VLAN configurations are maintained independently by the switch and take affect when the interface is configured in the relevant mode. In other words, trunk mode VLAN configuration only affects an interface when it is configured in trunk mode. When the interface is configured in trunk mode, access and general mode VLAN configuration is ignored. Layer 2 Switching Commands 879