Automatic Beacon Recovery Process
wrong ring speed. If a ring speed mismatch is detected, the STH disables the port to keep the misconfigured station isolated from the ring and provides a simple visible LED signal (blinking red at the port’s LED) to indicate to the user that Speed Fault Protection has disabled the port. The port remains disabled until the ring speed mismatch condition is removed or resolved.
Active Circuitry
On each TCU port, STH hubs provide active circuitry which filters, equalizes, and amplifies all received signals before transmitting them to the next point on the ring. The result is enhanced signal integrity and extended maximum station lobe cable distances.
Daughter Board Upgrade Kit
Both the
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1.2.3Automatic Beacon Recovery Process
To guard against interruptions in network operations due to beaconing conditions, the STH supports Cabletron Systems’ advanced Automatic Beacon Recovery Process which automatically partitions problematic lobes from the ring, allowing the rest of the ring to continue operating. (ABRP engages even before the IEEE standard beacon recovery process begins and is able to treat conditions beyond the scope of the IEEE process.) It is the stack’s intelligent hub that actually executes the ABRP algorithm. The intelligent hub also checks partitioned lobes periodically and
1.2.4Support for Passive MAU Workgroups
Whereas a station signals a TCU to open its interface by sending a phantom current down its lobe cable, a passive
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