RUGGEDCOM ROS
User Guide
Chapter 5
Setup and Configuration
GARP VLAN Registration Protocol (GVRP)
137
Section 5.1.1.8
GARP VLAN Registration Protocol (GVRP)
GARP VLAN Registration Protocol (GVRP) is a standard protocol built on GARP (Generic Attribute Registration
Protocol) to automatically distribute VLAN configuration information in a network. Each switch in a network needs
only to be configured with VLANs it requires locally. VLANs configured elsewhere in the network are learned
through GVRP. A GVRP-aware end station (i.e. PC or Intelligent Electronic Device) configured for a particular VID
can be connected to a trunk on a GVRP-aware switch and automatically become part of the desired VLAN.
When a switch sends GVRP bridge protocol data units (BPDUs) out of all GVRP-enabled ports, GVRP BPDUs advertise
all the VLANs known to that switch (configured manually or learned dynamically through GVRP) to the rest of the
network.
When a GVRP-enabled switch receives a GVRP BPDU advertising a set of VLANs, the receiving port becomes a
member of those advertised VLANs and the switch begins advertising those VLANs through all the GVRP-enabled
ports (other than the port on which the VLANs were learned).
To improve network security using VLANs, GVRP-enabled ports may be configured to prohibit the learning of any
new dynamic VLANs but at the same time be allowed to advertise the VLANs configured on the switch.
The following is an example of how to use GVRP:
A
A2
A1
D
D1
D2
B
B4
B3
B1
B2
C
C2
C1
E
E2
E1
D
E
A
C
1
2
Figure 77: Using GVRP
1.
Switch
2.
End Node
• Switch B is the core switch, all others are edge switches
• Ports A1, B1 to B4, C1, D1, D2 and E1 are GVRP aware
