Ring interworking between a bidirectional line-switched ring transmission system and another ring transmission system
CA 2065463 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 between a bidirectional line-switched ring transmission system and another ring transmission system is continued in the presence of the failure of a first shared node for communications circuits between the ring transmission systems by employing at least one additional shared node for the communications circuits; provisioning one or more duplex communications circuits between the first shared node and the additional shared node; and selectively allowing the one or more duplex communications circuits between the shared nodes to be established in the bidirectional line-switched ring when a ring node in the bidirectional line-switched ring in the first …
Read the whole patent
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 7, 1992 and granted December 22, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 7, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 7, 2014.
- 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.