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Expired Canadian patentCanada

Rerouting in a distributed telecommunication system

CA 2081168 C · Owner: Thieler, Stephen Max · Inventors: Thieler, Stephen Max; Bales, Bruce Merrill; Crumpley, Robert Louis

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Overview

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Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

Routing calls using a new protocol message which is a redirect message in a telecommunication system having a number of switching nodes to avoid circular paths among the switching nodes and for rerouting calls in the event of failures or overload conditions. During the establishment of a call from an originating switching node to a destination switching node where the call path has already been setup from the originating switching node through an intermediate switching node a, switching node is responsive to a setup message from the intermediate switching node requesting extension of the call path through the switching node to determine if such an extension would create a circular path. If …

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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 October 22, 1992 and granted April 8, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 22, 2012.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 22, 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.
FiledOctober 22, 1992
GrantedApril 8, 1997
Term endedOctober 22, 2012
Patent numberCA 2081168 C
Classification (IPC)H04Q3/42 +2 more

Timeline

Timeline From CIPO dates

1993199519971999200120032005200720092011Application filedOct 22, 1992Patent grantedApril 8, 1997Term endedOct 22, 2012

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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.