Allied Telesis AT-S60 - Manual (Page 292)

AT-S60 Management Software User’s Guide
Section II: Local and Telnet Management 291
The Applicant is therefore looking after the interests of all would-be
Participants. This allows the Registrar to be very simple.
The job of the Registrar is to record whether an attribute is registered, in
the process of being de-registered, or is not registered for an instance of
GID.
To control the Applicant state machine, an Applicant Administrative
Control parameter is provided. This parameter determines whether or
not the Applicant state machine participates in GARP protocol
exchanges. The default value has the Applicant participating in the
exchanges.
To control the Registrar state machine, a Registrar Administrative
Control parameter is provided. Basically this parameter determines
whether or not the Registrar state machine listens to incoming GARP
messages. The default value has the Registrar listening to incoming
GARP messages.
The propagation of information between GARP Participants for the same
Application in a switch is carried out by the GIP component. The
operation of GIP is dependent upon STP being enabled on a port, as only
ports in the STP Forwarding state are eligible for membership to the GIP
connected ring. Ports in the GIP connected ring propagate GID Join and
Leave requests to notify each other of attribute registrations and de-
registrations. The operation of GIP allows ports in the switch to share
information between themselves and the LANs/end stations to which
the ports are connected.
If a port enters the STP Forwarding state and the GARP application that
the port belongs to is enabled, then the port is added to the GIP
connected ring for the GARP application. All attributes registered by
other ports in the GIP connected ring is propagated to the recently
connected port. All attributes registered by the recently connected port
is propagated to all other ports in the GIP connected ring.
Similarly, if a port leaves the STP Forwarding state and the GARP
application that the port belongs to is enabled, then the port is removed
from the GIP connected ring for the GARP application. Prior to removal,
GID leave requests are propagated to all other ports in the GIP
connected ring if the port to be removed has previously registered an
attribute and no other port in the GIP connected ring has registered that
attribute. The operations of GIP can be enabled or disabled by user
command.