Browse Prior Art Database

Recovery From Transmission Medium Failures in a Ring

IP.com Disclosure Number: IPCOM000046490D
Original Publication Date: 1983-Jul-01
Included in the Prior Art Database: 2005-Feb-07
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Andrews, DW: AUTHOR [+5]

Abstract

This article describes an apparatus and method for automatic recovery from a fault occurring in a segment of a ring or a loop communication system. The ring or loop communication system is fitted with a backup ring. Electrical signals are forced to travel on the backup ring in a direction opposite to the direction in which signals are propagated on a prime ring. When a ring wiring concentrator (RWC) detects an outage on its upstream segment of the prime ring, the ring wiring concentrator connects the backup ring to the prime ring on the upstream side of the RWC. This causes the signal transmission on the backup ring to be discontinued, thereby alerting the upstream RWC. The alerted ring wiring concentrator then connects the prime ring to the backup ring. The new configuration enables normal ring operation.

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Recovery From Transmission Medium Failures in a Ring

This article describes an apparatus and method for automatic recovery from a fault occurring in a segment of a ring or a loop communication system. The ring or loop communication system is fitted with a backup ring. Electrical signals are forced to travel on the backup ring in a direction opposite to the direction in which signals are propagated on a prime ring. When a ring wiring concentrator (RWC) detects an outage on its upstream segment of the prime ring, the ring wiring concentrator connects the backup ring to the prime ring on the upstream side of the RWC. This causes the signal transmission on the backup ring to be discontinued, thereby alerting the upstream RWC. The alerted ring wiring concentrator then connects the prime ring to the backup ring. The new configuration enables normal ring operation.

The figure shows the ring or loop communication system. The communication system includes a plurality of ring wiring concentrators RWC1, RWC2, and RWC3. Each ring wiring concentrator is fitted with a ring adapter (RA). The ring wiring concentrators are coupled to one another by a prime ring 10. The prime ring carries all the data traffic which is propagated in the direction shown by the arrows. A plurality of ring stations (R1 and R2) is coupled through lobe wires to the ring wiring concentrators. A backup ring 12 is disposed relative to the prime ring and interconnects the ring wiring concentrators. The backup ring has drivers and receivers (not shown) in each wiring concentrator to generate and detect signals propagating along the backup ring. The signals, on the backup ring, are propagated in the direction opposite that of the signals in the prime ring.

In operation, suppose a r...