Security for controlled access systems
CA 2200508 C · Owner: At&T Corp. · Inventors: Bulfer, Andrew Frederick; Witschorik, Charles Arthur
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In order to gain access to a secured system a user must be able to enter, valid user identification information and must also have a remote wireless communication device such as a pager or cellular telephone having a number that is substantially unique to that user. When the user requests access to the secured system, the system places a call to the user's remote wireless communication device and sends that device revalidation information such as a random number generatedby the secured system. The user must return the revalidation information to the secured system to gain access. In an alternative embodiment another person (a, user-approver) has the remote wireless communication device and …
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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 20, 1997 and granted February 22, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 20, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 20, 2019.
- 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.