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While I'm sharing ghost stories...

If you're on a cable modem right now, did you know your downstream internet connection is happening over a video stream?

Yup. Downstream internet on DOCSIS is an MPEG2 transport stream, just like the TV you watch. Which does frame reordering, retransmission, etc etc. TCP in an MPEG2 stream. which itself smells an awful lot like TCP over RF

There was this moment when I went to work for Network Engineering at Time Warner Cable where they handed me the specs and giggled. A few minutes later, there's the sound of sungo yelling "ARE YOU KIDDING ME WITH THIS SHIT? THIS IS A PRANK RIGHT?" It was not a prank.

I should probably be more clear here.

Your internet connection.

It's a TV channel.

You know how like you change to channel 42 or whatever to see ESPN?

Yeah, there's a TV channel that is your internet connection. The downstream side of it as least.

@sungo and probably more than one channel. My gigabit connection from Comcast as I recall is 8 channels

@kusuriya Indeed. It's why some places can't get gig. Too many TV channels, too little remaining spectrum

@sungo yep that's why they are super chomping at the bit for the next DOCSIS standard that supports 10gbit. there is some compression and layering that will allow them to almost quadruple each channel.

@kusuriya Yeah. it's what, 2048 QAM now? Gonna need some shiny new wires for that. No copper laid by Thomas Edison for that connection.

@sungo yep 2048 QAM and yep it needs some high gauge wire it looks like reading the stuff from Bell Labs

@kusuriya It'll be interesting to see how big the distribution is for that. My gut says you need to either live real close to a node or have a super clean signal. There's just no wiggle room for intereference in 2048 QAM.

@sungo yeah my feeling is it's going to be one of those things that the foot print is narrow and only in new developments or large cities with s high node density.

@kusuriya I really do miss having a job where I had to / got to learn shit like this.

@sungo
I once tried to calculate how much data would fit into a #VHS cassette — got about 20 Go. Did not test…

@sungo So glad I haven't had a cable modem since 2006.

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hackers.town

A bunch of technomancers in the fediverse. Keep it fairly clean please. This arcology is for all who wash up upon it's digital shore.