1-3
GARP message format
Figure 1-1
GARP message format
Figure 1-1
illustrates the GARP message format.
Table 1-1
describes the GARP message fields.
Table 1-1
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
––
Attribute
Consists of an Attribute Length, an
Attribute Event, and an Attribute Value
––
Attribute Length
Number of octets occupied by an attribute,
inclusive of the attribute length field
2 to 255 (in bytes)
Attribute Event
Event described by the attribute
z
0: LeaveAll event
z
1: JoinEmpty event
z
2: JoinIn event
z
3: LeaveEmpty event
z
4: LeaveIn event
z
5: Empty event
Attribute Value
Attribute value
VLAN ID for GVRP
If the Attribute Event is
LeaveAll, Attribute Value is
omitted.
End Mark
Indicates the end of a GARP PDU
0x00
GVRP
GVRP enables a device to propagate local VLAN registration information to other participant devices
and dynamically update the VLAN registration information from other devices to its local database
