Virtual wide area centrex
CA 2174994 C · Owner: Bell Canada · Inventors: Turner, George W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and system is disclosed for providing wide area centrex services to a telephone network having a number of telephone switching offices equipped with SSPs (Service Switching Points) operating with AIN (Advanced Intelligent Network) application software. The network has a serving central office for providing centrex functionality to a number of customer sites each, served by separate central offices. A virtual telephone number is assigned to each station used at the customer sites. Each central office is connected to a service control point (SCP) having a number translation database containing the virtual number assignment. A dialed virtual number is translated to a real number to …
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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 25, 1996 and granted June 23, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 25, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 25, 2018.
- 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.