ZyXEL Communications ES-2024A, User Manual

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ES-2024A User’s Guide
66 Chapter 8 VLAN
8.2 Automatic VLAN Registration
GARP and GVRP are the protocols used to automatically register VLAN membership across
switches.
8.2.1 GARP
GARP (Generic Attribute Registration Protocol) allows network switches to register and de-
register attribute values with other GARP participants within a bridged LAN. GARP is a
protocol that provides a generic mechanism for protocols that serve a more specific
application, for example, GVRP
.
8.2.1.1 GARP Timers
Switches join VLANs by making a declaration. A declaration is made by issuing a Join
message using GARP. Declarations are withdrawn by issuing a Leave message. A Leave All
message terminates all registrations. GARP timers set declaration timeout values.
8.2.2 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 VLANs groups beyond the local switch.
Please refer to the following table for common GARP terminology.
Table 13 IEEE 802.1q 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/
deregistration 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 don't tag all outgoing
frames transmitted.