Method of operating a modem in the presence of interrupted dial tone
CA 2220829 C · Owner: Mitel Networks Corporation · Inventors: Tran, To Van
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
According to the present invention, a method is provided enabling an analog modem to dial out while a dial tone is interrupted or stuttered due to at least one unheard message at a Central Office for a subscriber to Call Answer is provided . Call Answer is an automated voice messaging system which causes the dial tone of a phone line connected to the modem, to be either interrupted or stuttered when a message is waiting for the subscriber. Users of the present invention are able to receive on-line access faster than users of the prior art. The method of the present invention implements a software program within the modem. By comparing the elapsed length of the dial tone with two …
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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 November 12, 1997 and granted January 2, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 12, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 12, 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.