Static Virtual LANs (VLANs)
802.1Q VLAN Tagging
■If all end nodes on a port comply with the 802.1Q standard and are configured to use the correct VID, then, you can configure all VLAN assignments on a port as “Tagged” if doing so either makes it easier to manage your VLAN assignments, or if the authorized, inbound traffic for all VLANs on the port will be tagged.
For a summary and flowcharts of untagged and tagged VLAN operation on inbound traffic, refer to the following under “VLAN Operating Rules” on pages
•“Inbound Tagged Packets”
•“Untagged Packet Forwarding” and figure
•“Tagged Packet Forwarding” and figure
Example. In the following network, switches X and Y and servers S1, S2, and the AppleTalk server are
AT1 (Protocol) VLAN:
Untagged
AppleTalk |
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| Red VLAN: Untagged |
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| Green VLAN: Tagged |
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| AT2 (Protocol) VLAN: |
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Apple | Red | Green | Red | Green | Apple | ||
Talk |
| Talk | |||||
| VLAN | VLAN | VLAN | VLAN | |||
VLAN | 1 | VLAN 2 | |||||
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