GVRP

Introduction

Note that if a static VLAN is configured on at least one port of a switch, and that port has established a link with another device, then all other ports of that switch will send advertisements for that VLAN.

For example, in the following figure, Tagged VLAN ports on switch “A” and switch “C” advertise VLANs 22 and 33 to ports on other GVRP-enabled switches that can dynamically join the VLANs.

Switch “A”

 

 

 

Switch “C”

 

 

GVRP On

1

5

 

GVRP On

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Tagged

 

 

 

 

 

 

 

 

 

 

 

 

 

11

VLAN 22

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Tagged

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

VLAN 33

 

 

12

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Switch “B”

 

 

Switch “D”

(No GVRP)

 

 

GVRP On

Tagged

3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

VLAN 22

 

 

 

 

 

 

 

 

 

 

 

 

 

 

6

Switch “D”:

Port 3 dynamically joins VLANs 22 and 33.

Port 6 dynamically joins VLAN 22 and 33.

Switch “C”:

Port 5 dynamically joins VLAN 22.

Ports 11 and 12 belong to Tagged VLAN 33.

2Switch “E” GVRP On

7

Switch “E”:

Port 2 dynamically joins VLANs 22 and 33. Port 7 dynamically joins VLANs 33 and 22.

Figure 3-2. Example of GVRP Operation

N o t e

A port can learn of a dynamic VLAN through devices that are not aware of

 

GVRP (Switch “B”, above). VLANs must be disabled in GVRP-unaware devices

 

to allow tagged packets to pass through.

 

 

A GVRP-aware port receiving advertisements has these options:

■If there is not already a static VLAN with the advertised VID on the receiving port, then dynamically create the VLAN and become a member.

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