Qtech QSW-3900-48-SFP-DC [72/245] Figure 1

QTECH Software Configuration Manual

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& Note :

· The settings of GARP timers apply to all GARP applications, such as GVRP, on a LAN.

· Unlike other three timers, which are set on a port basis, the LeaveAll timer is set in system

view and takes effect globally.

· A GARP application entity may send LeaveAll messages at the interval set by its LeaveAll

timer or the LeaveAll timer on another device on the network, whichever is smaller. This is

because each time a device on the network receives a LeaveAll message it resets its

LeaveAll timer.

5.3.3.1 Operating mechanism of GARP

The GARP mechanism allows the configuration of a GARP participant to propagate throughout a LAN

quickly. In GARP, a GARP participant registers or deregisters its attributes with other participants by making or

withdrawing declarations of attributes and at the same time, based on received declarations or withdrawals handles

attributes of other participants.

GARP application entities send protocol data units (PDU) with a particular multicast MAC address as

destination. Based on this address, a device can identify to which GVRP application, GVRP for example, should a

GARP PDU be delivered.

5.3.3.2 GARP message format

The following figure illustrates the GARP message format.

Figure 1 GARP message format

The following table describes the GARP message fields.

Table 1 Description on the GARP message fields

Field Description Value

Protocol ID Protocol identifier for GARP 1

Message One or multiple messages, each

containing an attribute type and an

attribute list

––

Attribute Type Defined by the concerned GARP

application

0x01 for GVRP, indicating

the VLAN ID attribute

Attribute List Contains one or multiple attributes ––