H3C Technologies H3C WX3000E Series Wireless Switches - Manual (Page 130)

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GARP PDU format
Figure 36 GARP PDU format
As shown in Figure 36 , GARP PDUs are encapsulated in IEEE 802.3 Ethernet frames.
Table 18 GARP PDU fields
Field Description Value
Protocol ID Protocol identifier for GARP 0x0001
Message
One or multiple messages, each containing
an attribute type and an attribute list
––
End mark Indicates the end of a GARP PDU 0x00
Attribute type Defined by the 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
Length of an attribute, inclusive of the
attribute length field
2 to 255 (in bytes)
Attribute event Event described by the attribute
• 0x00: LeaveAll event
• 0x01: JoinEmpty event
• 0x02: JoinIn event
• 0x03: LeaveEmpty event
• 0x04: LeaveIn event
• 0x05: Empty event
Attribute value Attribute value
VLAN ID for GVRP
If the value of the Attribute event field is
0x00 (LeaveAll event), the Attribute value
field is invalid.
Ethernet frame
Attribute length Attribute event Attribute value
DA SA Length DSAP SSAP Ctrl GARP PDU
Attribute list Attribute type
... Message n Message 1 Protocol ID End mark
... Attribute 1 Attribute n End mark