Static Virtual LANs (VLANs)

Port-Based Virtual LANs (Static VLANs)

 

■

In switch X:

 

 

• VLANs assigned to ports X1 - X6 can all be untagged because there is

 

 

only one VLAN assignment per port. Red VLAN traffic will go out only

 

 

the Red ports; Green VLAN traffic will go out only the Green ports,

 

 

and so on. Devices connected to these ports do not have to be 802.1Q­

 

 

compliant.

 

 

• However, because both the Red VLAN and the Green VLAN are

 

 

assigned to port X7, at least one of the VLANs must be tagged for this

 

 

port.

 

■

In switch Y:

 

 

• VLANs assigned to ports Y1 - Y4 can all be untagged because there is

 

 

only one VLAN assignment per port. Devices connected to these ports

 

 

do not have to be 802.1Q-compliant.

 

 

• Because both the Red VLAN and the Green VLAN are assigned to port

 

 

Y5, at least one of the VLANs must be tagged for this port.

 

■ In both switches: The ports on the link between the two switches must be

 

 

configured the same. As shown in figure 2-24(above), the Red VLAN must

 

 

be untagged on port X7 and Y5 and the Green VLAN must be tagged on

 

 

port X7 and Y5, or vice-versa.

 

 

N o t e

Each 802.1Q-compliant VLAN must have its own unique VID number, and that

 

VLAN must be given the same VID in every device in which it is configured.

That is, if the Red VLAN has a VID of 10 in switch X, then 10 must also be used for the Red VID in switch Y.

VID Numbers

Figure 2-25. Example of VLAN ID Numbers Assigned in the VLAN Names Screen

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