H3C S5100-SI Series Operation Manual page 142

Operation Manual – GVRP
H3C S5100-SI/EI Series Ethernet Switches
II. Operating mechanism of GARP
Through the mechanism of GARP, the configuration information on a GARP member
will be propagated within the whole LAN. A GARP member can be a terminal
workstation or a bridge; it instructs other GARP members to register/deregister its
attribute information by declaration/recant, and register/deregister other GARP
member's attribute information according to other member's declaration/recant. When
a port receives an attribute declaration, the port will register this attribute. When a port
receives an attribute recant, the port will deregister this attribute.
The protocol packets of GARP entities use specific multicast MAC addresses as their
destination MAC addresses. When receiving these packets, the switch distinguishes
them by their destination MAC addresses and delivers them to different GARP
application (for example, GVRP) for further processing.
III. GARP message format
The GARP packets are in the following format:
Figure 1-1 Format of GARP packets
The following table describes the fields of a GARP packet.
Table 1-1 Description of GARP packet fields
Protocol ID
Message
Attribute Type
Field
Protocol ID
Each message consists of
two parts: Attribute Type
and Attribute List.
Defined by the specific
GARP application
Description
1-3
Chapter 1 GVRP Configuration
Value
1
—
The attribute type of
GVRP is 0x01.