----- Original Message -----

From: "Brandon Butterworth" <brandon@rd.bbc.co.uk>

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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.

You demonstrate that you have no understanding of what the words "sneak along" mean. :-)

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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.

Allow you to sneak in extra data in an otherwise unused place that won't affect anything, and no one will have to deal with, but end viewers will be able to see it anyway? No, we're pretty sure you're wrong there, probably because you're purposely ignoring our *specific* characterization of the thing which was actually done.

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.

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

Sure. But that wasn't what we were *talking* about.

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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.

Nobody said it was, and what's more: we don't care. :-)

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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 can't really guarantee that random things injected into a transport stream mux at the send end will make it to the receive end; everyone in the transport path very likely thinks they're entitled to pull the separate program streams out and fiddle with them however they like -- Hell: local cablecos *reencode* the local station HD signals to compress them further. So not only are you not making assertions about the same thing we are, there's a very good chance you're incorrect in the general case about the assertion you *are* making. I don't know if my understanding of terrestrial network and satellite broadcasting in the US carries over to the continent, but I'd bet at least the latter does... Cheers, -- jra -- Jay R. Ashworth Baylink jra@baylink.com Designer The Things I Think RFC 2100 Ashworth & Associates http://baylink.pitas.com 2000 Land Rover DII St Petersburg FL USA http://photo.imageinc.us +1 727 647 1274