It was messy I know... |
Granted, I did the structured wiring myself, and this is an older picture (no longer have the 3800 on the wall and the temp cables everywhere) but it gives you a sense of what they would do for a pure Ethernet install...
I used blue CAT6 patch cables for Data outlets, and orange for TV outlets, and on the wall the TV outlet is also orange.
Most newer homes with structured wiring should already have a CAT5 homerun to the panel from the NID as part of the install... Ones that I've worked on since 2004-5 around here had at least that. My house was 1999 and had CAT3 daisy-chained everywhere for phone (replaced with CAT5 so if I needed a quick network connection I could swap it at the panel)
Depending on the setup, they would use a pair from the NID in, connect it to the modem, select another pair back out to the nid to attach to phones or use the jack in the modem to plug into the phone bridge board.
Ethernet by nature is point to point connection. If a STB goes down, it would not affect the others. If the DVR goes down, you can't see recorded shows, but other STBs should still work. If the gateway goes down, then everything is down.