3Com LINKBUILDER 3C18500, User Manual

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DUA1850-0AAA05
The figure above shows both ports being wrapped with the result that
the ring components connected to the chassis become separated from
the external ring. Wrapped mode is useful in helping to trouble shoot
faults on the network.
In the wrapped state the RingBuilder will still perform retiming on the
external ring.
FAIL-SAFE mode - In FAIL-SAFE mode, the Ring-In and Ring-Out
ports operate as if in the OPEN mode, until the RingBuilder detects
a cable fault between the Ring-In and Ring-Out ports on another
RingBuilder Module. At this point the RingBuilder will automatically
wrap the ring at the faulty port onto the backup path. This feature
is only operational if the RingBuilder is connected to other
RingBuilder Module(s), or other LinkBuilder token ring products that
support a dual ring.
Ring Topology and Sizing
Cable type, ring speed and ring topology affect the performance of the
token ring. Using management commands to change port
configurations will affect the ring topology. You may experience a
detrimental effect on ring performance unless you properly consider
these factors and how they interact.
Ring Speed
The RingBuilder is set by switches, to operate its token ring at a speed
of 4 Mbps or 16 Mbps.
It is important to remember that the higher ring speed will reduce the
cable lengths that are allowed.
Retiming and Station Count
Each attached station on the ring retimes the signals passing around
the ring. The number of such retiming operations is referred to as the
Station Count. MSH Token Ring MAUs, and RingBuilder Modules
contribute to the Station Count: the RingBuilder counts as three