A virtual private switched telephone network
CA 2428472 A1 · Owner: Heilmann, Craig · Inventors: Pickens, Keith S.; Heilmann, Craig; Schmid, Gregor
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system and method to provide secure access across the untrusted public switched telephone network (116) is described. The system and method can be initiated by a security policy defining actions including conducting the call , in secure mode to be taken based upon at least one detected attribute of the call.
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 November 9, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 9, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 9, 2023.
- 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.