How a cable modem works (c. 2002)
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How a cable modem works (c. 2002)
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Re: How a cable modem works (c. 2002)
#2https://news.ycombinator.com/item?id=31358855#31362310
MoCA: run your ethernet over the cable tv coax in your house
Re: How a cable modem works (c. 2002)
#3> All data that is present on the downstream is encapsulated into MPEG-2 frames.
In other words, “you’re now watching The Internet Channel(tm)”
Re: How a cable modem works (c. 2002)
#4Does anyone remember early cable modems allowing viewing other computers? What allowed that to happen?
I didn't know enough about networking at the time, but I recall seeing this at friends houses in maybe the late 90's. You could go into "Networking" in Windows, and see basically all the PCs on the street/neighborhood. I assume this was with the PC directly connected (no router) and maybe using WINS, but I'd be curious if there's more details behind why this could even happen. Did this also mean you'd be able to sniff other people's network traffic?
Re: How a cable modem works (c. 2002)
#5[deleted]
Re: How a cable modem works (c. 2002)
#6> That 6 MHz is used to encode MPEG-2 frames containing video, color, and audio information that your cable box or TV decodes into picture and sound. If you graphed a single channel provided by the cable operator, it would look similar to Figure 2-2.
> A DOCSIS channel can be graphed in the same fashion; however, instead of video, color, and audio information inside the MPEG-2 frames, it contains a data stream that represents computer information. Due to the "spectral shaping" of a data signal, there are no video or audio signals present, and the graph looks like Figure 2-3.
this seems wrong. i think figure 2-2 is an analog ntsc video channel and figure 2-3 is a digital mpeg-2 or docsis over mpeg-2 channel. both of the digital channels should have the same spectral envelope.
interesting that they put mpeg-2 headers on the data frames, probably "system" frames and done so for compatibility with existing headend and stb equipment.
Re: How a cable modem works (c. 2002)
#7Does anyone remember early cable modems allowing viewing other computers? What allowed that to happen? I didn't know enough about networking at the time, but I recall seeing this at friends houses in maybe the late 90's. You could go into "Networking" in Windows, and see basically all the PCs on the street/neighborhood. I assume this was with the PC directly connected (no router) and maybe using WINS, but I'd be curi…
Essentially you were linked into badly managed network that inter-routed clients on the head end side, without isolating clients. Often with ethernet emulation involved if not straight ethernet going on.
Essentially, routing done badly by ISP.
Re: How a cable modem works (c. 2002)
#8Does anyone remember early cable modems allowing viewing other computers? What allowed that to happen? I didn't know enough about networking at the time, but I recall seeing this at friends houses in maybe the late 90's. You could go into "Networking" in Windows, and see basically all the PCs on the street/neighborhood. I assume this was with the PC directly connected (no router) and maybe using WINS, but I'd be curi…
I do! It was before they started blocking NetBIOS over TCP/IP.
Re: How a cable modem works (c. 2002)
#9> All data that is present on the downstream is encapsulated into MPEG-2 frames. In other words, “you’re now watching The Internet Channel(tm)”
Only slightly more ridiculous than the ADSL encapsulation stack.
Re: How a cable modem works (c. 2002)
#10Does anyone remember early cable modems allowing viewing other computers? What allowed that to happen? I didn't know enough about networking at the time, but I recall seeing this at friends houses in maybe the late 90's. You could go into "Networking" in Windows, and see basically all the PCs on the street/neighborhood. I assume this was with the PC directly connected (no router) and maybe using WINS, but I'd be curi…
I do recall this. There were so many insane networking issues that cropped up in the early days of "always-on" internet.