3Com LINKBUILDER 3C18500, User Manual

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Isolated RingBuilders
A RingBuilder Module will operate as a stand-alone device if its local
ring section number does not match that of any other token ring
module in the chassis, or if its local ring section number is set to zero.
In stand-alone mode the RingBuilder will not construct a local ring
section in the MSH chassis and consequently cannot monitor the
operation of any MAUs within the chassis. However, if the RingBuilder’s
Ring-In and Ring-Out ports are connected to an external ring, the
RingBuilder can monitor the operation of the external ring.
Isolated Token Ring MAUs
A MAU is isolated when its local ring section number does not match
that of a RingBuilder or when its local ring section number is Zero.
Isolated MAUs do not communicate with any other module in the
MSH chassis. Instead, the MAU connects the output from its last port to
the input of its first port, so that the stations connected to the ports on
the MAU operate as a separate ring. All ports on an isolated MAU are
enabled: see figure below.
Figure 9-8 Isolated MAUs
An isolated MAU module cannot be managed, with the exception that
its local ring section number can be changed through VT100
Management: see “ Facility Table ” on page 11-20 . Up to 11 isolated
MAUs can coexist in an MSH chassis.