Chapter 49 VLAN
GS1920v2 Series User’s Guide
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GVRP
GVRP (GARP VLAN Registration Protocol) is a registration protocol that defines a way for switches to 
register necessary VLAN members on ports across the network. Enable this function to permit VLAN 
groups beyond the local Switch.
Please refer to the following table for common IEEE 802.1Q VLAN terminology.
49.2.0.2  Port VLAN Trunking
Enable VLAN Trunking on a port to allow frames belonging to unknown VLAN groups to pass through 
that port. This is useful if you want to set up VLAN groups on end devices without having to configure the 
same VLAN groups on intermediary devices.
Refer to the following figure. Suppose you want to create VLAN groups 1 and 2 (V1 and V2) on devices 
A and B. Without VLAN Trunking, you must configure VLAN groups 1 and 2 on all intermediary switches C, 
D and E; otherwise they will drop frames with unknown VLAN group tags. However, with VLAN Trunking 
enabled on ports in each intermediary switch you only need to create VLAN groups in the end devices 
(A and B). C, D and E automatically allow frames with VLAN group tags 1 and 2 (VLAN groups that are 
unknown to those switches) to pass through their VLAN trunking ports.
Figure 209   Port VLAN Trunking
Table 156   IEEE 802.1Q VLAN Terminology
VLAN PARAMETER TERM DESCRIPTION
VLAN Type Permanent VLAN This is a static VLAN created manually.
Dynamic VLAN This is a VLAN configured by a GVRP registration or de-registration 
process.
VLAN Administrative 
Control
Registration Fixed Fixed registration ports are permanent VLAN members.
Registration 
Forbidden
Ports with registration forbidden are forbidden to join the specified 
VLAN.
Normal Registration Ports dynamically join a VLAN using GVRP.
VLAN Tag Control Tagged Ports belonging to the specified VLAN tag all outgoing frames 
transmitted.
Untagged Ports belonging to the specified VLAN do not tag all outgoing 
frames transmitted.
VLAN Port Port VID This is the VLAN ID assigned to untagged frames that this port 
received.
Acceptable Frame 
Type
You may choose to accept both tagged and untagged incoming 
frames, just tagged incoming frames or just untagged incoming 
frames on a port.
Ingress filtering If set, the Switch discards incoming frames for VLANs that do not 
have this port as a member.