KYLAND Technology SICOM3024P, Web Operation Manual

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Advanced Configuration
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6.21 GMRP Configuration and Query
6.21.1 GARP
The Generic Attribute Registration Protocol (GARP) is used for distributing, registering, and
cancelling certain information (VLAN, multicast address) among switches on the same
network. GARP applications include GVRP and GMRP.
With GARP, the configuration information of a GARP member will distribute the information
to the entire switching network. A GARP member instructs the other GARP members to
register or cancel its own configuration information by means of join/leave message
respectively. The member also registers or cancels the configuration information of other
members based on join/leave messages sent by other members.
GARP involves three types of messages: Join, Leave, and LeaveAll.

When a GARP application entity wants to register its own information on other switches,
the entity sends a Join message. Join messages fall into two types: JoinEmpty and JoinIn.
A JoinIn message is sent to declare a registered attribute, while a JoinEmpty message is
sent to declare an attribute that is not registered yet.

When a GARP application entity wants to cancel its own information on other switches,
the entity sends a Leave message.

After a GARP entity starts, it starts the LeaveAll timer. When the timer expires, the entity
sends a LeaveAll message.
Note:
An application entity indicates a GARP-enabled port.
GARP timers include Hold timer, Join timer, Leave timer, and LeaveAll timer.

Hold Timer : When receiving a registration message, a GARP entity does not send a Join
message immediately, but starts a Hold timer. When the timer expires, the entity sends all
the registration messages received within the preceding period in one Join message,
reducing packet sending for better network stability.

Join Timer : To ensure that Join messages are received by other application entities, a
GARP application entity starts a Join timer after sending a Join message. If receiving no