Port-Based Virtual LANs (VLANs) and GVRP

 

 

 

 

 

 

 

 

 

 

Port-Based Virtual LANs (Static VLANs)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Server

 

 

 

Server

 

 

 

 

 

 

S1

 

 

 

 

S2

 

 

 

 

 

 

Red VLAN: Untagged

 

 

 

Red VLAN: Untagged

 

 

 

 

 

Green VLAN: Tagged

 

 

 

Green VLAN: Tagged

 

 

 

 

 

 

 

 

Red VLAN: Untagged

 

 

 

 

 

 

 

 

 

 

X1

 

 

 

Y1

 

 

 

 

 

 

 

Switch X2

Green VLAN: Tagged

 

Y5 Switch Y2

Green VLAN only

Server

 

 

 

 

 

 

 

 

 

"X"

 

 

 

 

 

"Y"

 

S3

 

 

 

X4

X3

 

 

Y4

Y3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Red

Green

 

Red

 

Green

 

 

VLAN

VLAN

VLAN

 

VLAN

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 11-19. Example of Networked 802.1Q-Compliant Devices with MultipleVLANs on Some Ports

The VLANs assigned to ports X3, X4, Y2, Y3, and Y4 can all be untagged because there is only one VLAN assigned per port. Port X1 has multiple VLANs assigned, which means that one VLAN assigned to this port can be untagged and any others must be tagged. The same applies to ports X2, Y1, and Y5.

Switch X

 

 

Switch Y

 

Port

Red VLAN

Green VLAN

 

Port

Red VLAN

Green VLAN

 

 

 

 

 

 

 

X1

Untagged

Tagged

 

Y1

Untagged

Tagged

X2

Untagged

Tagged

 

Y2

No*

Untagged

X3

No*

Untagged

 

Y3

No*

Untagged

X4

Untagged

No*

 

Y4

Untagged

No*

 

 

 

 

Y5

Untagged

Tagged

 

 

 

 

 

 

 

*”No” means the port is not a member of that VLAN. For example, port X3 is not a member of the Red VLAN and does not carry Red VLAN traffic. Also, if GVRP were enabled, “Auto” would appear instead of “No”.

N o t e

VLAN configurations on ports connected by the same link must match.

 

Because ports X2 and Y5 are opposite ends of the same point-to-point connec­

 

tion, both ports must have the same VLAN configuration; that is, both ports

 

configure the Red VLAN as “Untagged” and the Green VLAN as “Tagged”.

 

 

11-25