Patent CA1290431C successfully refreshed from Google Patents.
CA1290431C
Expired / Lapsed
CA
⏱️ 0.0 years remaining
Protection switching in a multi-channel communications system
Assignee: Nortel Networks Ltd
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Filing: 1987-07-31
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Granted: 1991-10-08
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Expires: 2007-07-31
Abstract
Abstract PROTECTION SWITCHING IN A MULTI-CHANNEL COMMUNICATIONS SYSTEM In a multi-channel, multi-site communications sytem, spans on working channels extending in an overlapping manner among the sites are afforded protection by a protection channel in accordance with a priority scheme. Enabling of protection switching for each span in the event of a signal failure on the span is dependent upon whether there is any protected higher priority overlapping span. This is determined individually for each span in response to each change in protection requests in the system.
Inventors
- 👤 David Ian Reid
- 👤 Kenneth Andrew Bobey
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-10-29 05:45
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
150 words
In a communications system having a plurality of working channels and a protection channel extending among a plurality of at least three sites, the working channels including a plurality of spans each extending via a communications channel between respective transmit and receive sites and having a predetermined priority for protection switching of traffic on the span via the protection channel between said sites, a method of facilitating protection switching in response to protection requests comprising the steps of, individually for each span in response to a change in protection requests in the system: effecting a protection switch for the respective span if there is a protection request for this span and there is no protection request for any higher priority overlapping span; and otherwise enabling a protection switch for the respective span in response to a fault condition of the span if there is no protected higher priority overlapping span.
Claim 2
Dependent Claim
150 words
In a communications system having a plurality of working channels and a protection channel extending among a plurality of at least three sites, the working channels including a plurality of spans each extending via a communications channel between respective transmit and receive sites and having a predetermined priority for protection switching of traffic on the span via the protection channel between said sites, a method of facilitating protection switching in response to protection requests comprising the steps of, individually for each span in response to a change in protection requests in the system: effecting a protection switch for the respective span if there is a protection request for this span and there is no protection request for any higher priority overlapping span; and otherwise enabling a protection switch for the respective span in response to a fault condition of the span if there is no protected higher priority overlapping span.
Claim 3
Dependent Claim
63 words
A method as claimed in claim 1 wherein for each respective span each each determination of the protection status of any higher priority overlapping span comprises the steps of: creating a list of all spans having a protection request and having a higher priority for protection switching than the respective span; and determining whether a span in said list overlaps the respective span.
Claim 4
Dependent Claim
93 words
A method as claimed in claim 2 wherein the determining step comprises the steps of: (a) determining whether the list is empty, if so indicating that there is no higher priority overlapping span, and if not continuing to step (b); (b) determining whether the highest priority span in the list overlaps the respective span, if so indicating that there is a higher priority overlapping span, and if not continuing to step (c) (c) eliminating from the list the highest priority span and any other span which overlaps it, and returning to step (a).
Claim 5
Dependent Claim
21 words
A method as claimed in claim 2 or 3 wherein said list is sorted in order of priority for protection switching.
References Cited (Backward Citations)
No citation records indexed.
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