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How the f*ck does a modem work?
(alien.top)
A community to help people learn, install, set up or troubleshoot their home network equipment and solutions.
But all these layers exist on both sides of a modem. Really the modem is translating between a type of physical/data layer on one side (e.g. twisted pair ethernet) to a different physical/data layer on the other side (e.g. docsis)
That's why technically, it's a "bridge". When DOCSIS was deployed for the consumer market, marketing continued to sell the electronics box at the point of demarcation (DEMARC) as a "modem".