Dual hubbing in a bidirectional line-switched ring transmission system
CA 2094541 C · Owner: American Telephone And Telegraph Company · Inventors: Kremer, Wilhelm
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Communications circuit connectivity in a bidirectional line-switched ring transmission system is continued in the presence of the failure of a first ring, node for communications circuits terminated in the ring node which are redirectable, to an alternate (dual hubbing) ring node. The communications circuits are redirected, by establishing a bidirectional communications circuit to the alternate ring node. In, one example, redirection of the communications circuits is further realized by not, squelching communications circuits terminated in the failed ring node in a ring node, adjacent the failed ring node on one prescribed side which normally would have been squelched, while …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed April 21, 1993 and granted November 2, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 21, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 21, 2015.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.