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Comment: Re:Of course... (Score 2, Funny) 637

by El_Isma (#39763281) Attached to: I believe humanity will first achieve ...

How to spot a Windows user:

It's like trying to move an already installed OS from one machine to another; difficult at best.

(I've moved dozens of Linux installs from one server to another and the only change I have to make is tell it "eth0 doesn't exist anymore" so I can have the interfaces named from eth0 onwards instead of eth1,2,3,4,... )

Comment: Re:Changing TV channels (Score 1) 297

by El_Isma (#36017190) Attached to: The Insidious Creep of Latency Hell

Digital cable normally works unidirectionally, think multicast. The header sends information for all the receivers, is not point to point like the internet. So, it doesn't matter that you don't want to see the channel, they still have to send it because somebody else *might* want to see it. And, yes, the channel guide travels in the "background".

Comment: Re:Changing TV channels (Score 2) 297

by El_Isma (#36017162) Attached to: The Insidious Creep of Latency Hell

That's due to how digital cable works. I'll speak of DVB since that's what I know (I don't know what USA is using, but surely it will be similar). DVB sends a big stream composed of several smaller streams, some of those are video/audio streams, some are channel information (the guide, the streams IDs (audio/video/cc) of the channel, etc), others are info on the stream itself (carrier frequencies) or general information (time).

For the video stream, as the parent poster said, you'll have to wait to get a keyframe to start to view it (sending more keyframes means less efficient coding, means more bandwith per channel).

For some of the channel information, like the guide, you have a tradeoff between bandwidth and latency. Sure, you can stream the guide with almost 0 latency, but that means using a lot of BW to be able to send all the channel guides all the time. You have less available BW for channels, which means having to use more carrier freqs which means more money on hardware to send those signals (and possibly repeaters...). So, cable operators send the guide with a "reasonable" BW. The problem gets worse the more channels you have, since the channel guide has to be sent on all carriers.

Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (2) Thank you for your generous donation, Mr. Wirth.