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Re: Re Netflix Is Eating Up More Of North America's Bandwidth Than Any Other Company


From: Robert Bonomi <bonomi () mail r-bonomi com>
Date: Thu, 26 May 2011 01:23:27 -0500 (CDT)


Date: Thu, 26 May 2011 02:08:04 +0100 (BST)
From: Brandon Butterworth <brandon () rd bbc co uk>
Subject: Re: Re Netflix Is Eating Up More Of North America's Bandwidth Than Any
      Other Company

You demonstrate you have no understanding of what the word 'feasable'
means.

OK, but we actually did this as a commercial service on analogue TV and
we deliver non picture data on digital TV (satellite and terrestrial)
today, it's just not USENET data.

One _cannot_ do this with 'modern' digital TV trasmission, because the
_end-to-end_ technolgy does not support it.

Apologies for disagreeing, but this is exactly what the modern
technology does.

NAME five consumer-grade commercial off the shelf products 

Digital TV (ATSC in your case, DVB-T & DVB-S in our case) has a
multiplex of a number of independent data streams that can be data,
video or audio. That is carried end to end.

That is *VERY* RARELY true in the U.S., in point of actual fact, as soon as
a 'cable TV'  carrier/distributer gets involved.  *THEY*, the cable companies,
de-multiplex the streams from the originator's composite signal, and
*selectively* re-encode the streams they wish to propogate on _separate_
QAM channels.  

Proof: go to Titantv.com, select the 'digital cable' channel line-up for
'Comcast areas 1, 4 & 5' in zipcode 60640 (chicago north side, lakefront).
and check the comcast channels in the range 340-379.  These  are all 
cable-company _de-multiplized_ video streams extracted from the multiplexed
stream from the originator.  The 'primary' (only!) HD video streams for those
channels can be found, mostly, on channels in the range, 187-194.

I'll simply ask, _which_ of those channels will have that extra data stream
that the head-end inserted?  That the cable compmany doesn't know, or care,
about, and *how* does it survive the de-multiplexing and re-coding that the
cable company did?

We do this now with other data -

http://en.wikipedia.org/wiki/BBC_Red_Button

It'd be trivial for us to display USENET directly to read on your TV
or deliver it to the STB ethernet port

You might be able to do it, if you control everything from  the point of  
rigin -through- the STB.

OTOH, if the signal originates as a digital stream, while it may be
"possible" to multiplex in an additional data stream, said data stream
will *NOT* survive _intermediate_ transcoding to an analog video stream 
before transmission to the end-user.

Indeed but that is not a digital TV system.

Tell that to all the U.S. cable companies that do _exactly_ that, and sell
it as 'digital' TV -- because they have re-encoded each derived analog video
stream as a QAM "digital" channel.

And, even if the actual digital
stream is delivered to the end-user, a *STANDARD* digital TV receiver has
no means to deliver that 'additional' information to the end-user in any
usableform.

Standard DTV PVR with an ethernet port are a few hundred dollars.

For the people who would actually receive this the box cost is trivial
they just some software. If you have a USB or PCI DTV rx it is trivial
to do whatever you like with the data.

You apparently have no idea how 'digital TV' is delivered by all the major
cable companies in the U.S. -- demultiplexed, and transcoded to QAM with 
each video stream on a separate QAM channel.  I don't see any _possible_
way for an additional data stream to survive _that_, without explicit 
intervention/support from the cable company.




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