User`s manual

Configuring GVRP
Maintaining consistent VLAN membership information across different switches in a company's network is
essential for creating and maintaining a reliable VLAN structure.
GARP
To make it possible to manage and distribute VLAN membership information to different switches through the
LAN, the IEEE defined the Generic Attribute Resolution Protocol (GARP), a dynamic protocol that is currently
applied in two variations :
GARP Multicast Registration Protocol (GMRP)
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GARP VLAN Registration Protocol (GVRP)●
GMRP
In GMRP, a device can create or request membership in a multicast domain.
GVRP
In GVRP, a device can create or request admission to a specific VLAN. GVRP devices can declare that they
want to join or leave an existing VLAN and learn about the VLAN membership on other devices. GVRP simplifies
VLAN management in large networks.
GVRP devices
GVRP devices include switches, routers and network interface cards. End stations and servers connected to
GVRP-enabled switches or routers must have NIC cards that support GVRP.
The Switch's GVRP capabilities:
Enabling GVRP on your Switch means the Switch can:
dynamically create a port-based VLAN based on updates from other GVRP-enabled devices
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learn and update an existing port-based VLAN by receiving GVRP updates from other GVRP devices, as
well as reading VLAN information contained in 802.1Q tagged packets coming into the Switch
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send dynamic GVRP updates about its existing port-based VLANs to other GVRP devices●
Two GVRP scenarios
There are two general GVRP network situations—GVRP activities between switches and GVRP activites
between an end station and a switch.
GVRP activities between switches and routers
With GVRP enabled, switches exchange VLAN configuration information with other GVRP switches,
prune unnecessary broadcast and unknown unicast traffic, and dynamically create and manage VLANs
on switches connected through 802.1Q trunk ports. Your GVRP-enabled Switch can advertise your
manually configured VLANs to other devices running GVRP. You do not have to manually configure
VLANs on these other devices. When other GVRP devices receive these advertisements, they can
forward 802.1Q packets to their proper destination.
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GVRP activities between an end station and a switch
When a GVRP-enabled application runs on an end station, the end station application begins the " join"
process by issuing a GVRP PDU that says "I want to join this VLAN". A typical example would be a user
wanting to join a corporate training session or video conference. The end station's switch exchanges
VLAN configuration information with other GVRP switches along the path to the video server.
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Basic GVRP switch configuration
The most common GVRP switch configuration is:
create an 802.1Q trunk port on each GVRP-enabled switch or router on your network
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enable GVRP on all switches●
enable tagging on each 802.1Q trunk port●
set the 802.1Q trunk port to admit tagged packets●
To configure GVRP, see:
Configuring GVRP - Command Line●
Configuring GVRP - Web●
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