VLAN CONFIGURATION

Tag-based VLANs

An IEEE 802.1Q VLAN is a group of ports located anywhere in the network, but communicate as though they belong to the same physical segment by using frame tags to indicate VLAN membership. Tagged VLANs can help to simplify network management by allowing you to move devices to a new VLAN without having to change any physical connections. You can also configure the switch to interoperate with existing tag-based VLAN networks and legacy non-tag networks by specifying whether or not the switch ports transmit tagged frames.

Assigning Ports to VLANs – You must assign each port to the VLAN group(s) in which it will participate. By default all ports are assigned to VLAN 1 as untagged ports. Add a port as a tagged port if you want it to carry traffic for one or more VLANs, and any intermediate network devices or the host at the other end of the connection supports VLANs. Then assign ports on the other VLAN-aware network devices along the path that will carry this traffic to the same VLAN(s), either manually or dynamically using GVRP. However, if you want a port on this switch to participate in one or more VLANs, but none of the intermediate network devices nor the host at the other end of the connection supports VLANs, then you should add this port to the VLAN as an untagged port.

Note: VLAN-tagged frames can pass through VLAN-aware or VLAN- unaware network interconnection devices, but should not be used for any end-node host that does not support VLAN tagging.

VLAN Classification – When the switch receives a frame, it classifies the frame in one of two ways. If the frame is untagged, the switch assigns the frame to an associated VLAN (based on the PVID of the receiving port). If the frame is tagged, the switch uses the tagged VLAN ID to identify the port broadcast domain of the frame.

Port Overlapping – Port overlapping can be used to allow access to commonly shared network resources among different VLAN groups, such as file servers or printers. Note that if you implement VLANs which do

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SMC Networks SMC6709L2 manual Tag-based VLANs