Detection of duplicate participants in a two-way modem environment
CA 2359607 A1 · Owner: General Instrument Corporation · Inventors: Anderson, Steven E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Duplicate participants (e.g. cloned subscriber units) (274) are detected in a communication network, such as a hybrid fiber/coax (HFC) cable television network or the like, by monitoring the physical layer of the network to detect transmission differences between such units. The subscriber units (14 16, 18, 274, 276) may be cable modems that transmit upstream signals with associated identifers to a headend (10, 200), e.g. to access the Internet or for telephony. Measured characteristics of the upstream signals can include: (1) propagation time (235), (2) frequency (240) (3) power (245), and (4) spectral , characteristics (250). For propagation time the reception time of the , upstream …
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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 January 14, 2000. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 14, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 14, 2022.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.