Method for testing call waiting, caller id functionality of telephone line
CA 2239247 A1 · Owner: Kennedy, Michael · Inventors: Coleman, James D.; Kennedy, Michael
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The control software of a central office-installed ringback test device is augmented to allow a craftsperson to test the operability of a caller identification call-waiting (CIDCW), class of service of a line without participation of another technician at the central office. Rather than instructing the craftsperson to go back on-hook the SASS's microcontroller, maintains the trunk circuit through which the incoming call is coupled to the SASS in a suspended, continuously monitored state so as to effectively busy out the calling line. The SASS then places a return call to the calling number by way of the ringback line which, by-passes the trunk, to the central office switch. If the line …
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 June 1, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 1, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 1, 2020.
- 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.