3Com 4200G 12-Port, Руководство по настройке

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13
GVRP C
ONFIGURATION
Introduction to GVRP
GVRP (GARP VLAN registration protocol) is an application of GARP (generic attribute
registration protocol). GVRP is based on the mechanism of GARP; it maintains
dynamic VLAN registration information and propagates the information to other
switches.
GARP is a generic attribute registration protocol. This protocol provides a mechanism
for the switching members in a switched network to register, distribute and
propagate information about VLANs, multicast addresses, and so on between each
other.
After the GVRP feature is enabled on a switch, the switch can receive the VLAN
registration information from other switches to dynamically update the local VLAN
registration information (including current VLAN members, which ports these VLAN
members get to, and so on), and propagate the local VLAN registration information
to other switches so that all the switching devices in the same switched network can
have the same VLAN information. The VLAN registration information includes not
only the static registration information configured locally, but also the dynamic
registration information from other switches.
GVRP Mechanism GARP Timers
The information exchange between GARP members is completed by messages. The
messages performing important functions for GARP fall into three types: Join, Leave
and LeaveAll.
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When a GARP entity expects other switches to register certain attribute
information of its own, it sends out a Join message.
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When a GARP entity expects other switches to unregister certain attribute
information of its own, it sends out a Leave message.
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Once a GARP entity starts up, it starts the LeaveAll timer. After the timer times out,
the GARP entity sends out a LeaveAll message.
The join message and the Leave message are used together to complete the
unregistration and re-registration of information. Through message exchange, all the
attribute information to be registered can be propagated to all the switches in the
same switched network.
GARP has the following timers:
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Hold: When a GARP entity receives a piece of registration information, it does not
send out a Join message immediately. Instead, to save the bandwidth resources, it
starts the Hold timer, puts all registration information it receives before the timer
times out into one Join message and sends out the message after the timer times
out.
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Join: To transmit the Join messages reliably to other entities, a GARP entity sends
each Join message two times. The Join timer is used to define the interval between
the two sending operations of each Join message.
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Leave: When a GARP entity expects to unregister a piece of attribute information,
it sends out a Leave message. Any GARP entity receiving this message starts its