Configuring Modules - 3Com 3C780 - LinkBuilder FDDI Base Unit User Manual

Table 3-4. Definitions for the Port Connection Rules (continued)
Condition
Indicator
W
T
The connections listed below are not allowed:
The connection rules do not necessarily prevent undesirable connections. An
"undesirable connection" designation reflects the connection status of the
sending node only. The connection can still be made if the receiving node
exhibits an acceptable connection status.

Configuring Modules

You can only configure the module inserted in slot 1, and you can only
configure the two leftmost ports (the attachment ports) of that module. The
attachment port configuration is stored in nonvolatile RAM. Any attachment
port configuration changes that you make take effect when the system is
reinitialized. To reinitialize the hub, execute the reset command.
Port Connection
Condition
Wrap state
Twisted ring
M to M: an illegal connection
A to A: an undesirable connection that creates a twisted ring
B to B: an undesirable connection that creates a twisted ring
Configuring the Hub
Definition of Port
Condition
Exists when a break in the
primary ring occurs and the
stations on either side of the
break join the primary and
secondary rings. It can also
indicate that the ring is
wrapped at a particular port.
Exists when an A-to-A or a
B-to-B connection is formed.
It divides the network into
two groups of stations that
disagree on which token ring
is the primary ring.
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