Mode shifting communications system and method
CA 2559912 C · Owner: Tummalapenta, Satyanarayana · Inventors: Ahya, Deepak P.; Kaushik, Sriram K.; Tummalapenta, Satyanarayana
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A digital network based communications system that establishes communications sessions to communicate via a simulated circuit-switched environment. Exemplary embodiments communicate between a first communications station and a second communications station using Voice over Internet Protocol (VOIP) techniques. Calls are setup, maintained and torn down using Session Initiation Protocol and Session Description Protocol messages. Call modes are able to be changed between duplex (404) and simplex (416) without disconnection. Duplex calls are able to be interrupted with a request for a simplex call (406) accept the simplex call (410) or send a response message (424) and then , resume the …
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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 March 10, 2005 and granted May 8, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 10, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
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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.