[opendtv] Re: Doug Lung series on OFDM

  • From: Craig Birkmaier <craig@xxxxxxxxx>
  • To: opendtv@xxxxxxxxxxxxx
  • Date: Thu, 15 Nov 2012 11:13:27 -0500

At 3:14 PM -0600 11/14/12, Manfredi, Albert E wrote:
No need to even cache anything. The way this can work is, a user stores his preferences in the receiver. When the ad breaks occur, the broadcaster transmits a "baseline" ad with the main program stream, and then a small number of additional ads, each one with its identifying IP multicast destination address. During ad breaks (i.e. when the IP multicast is seen by the receiver), if a user has stated preferences, the receiver will replace the "baseline" ad with the targeted ad. This is doable, and it is doable with full backward compatibility.

Yes this is doable in an ideal world. But the station may not have the bits necessary to execute this strategy, especially in markets like yours, where almost every station is already multicasting. And even if they can squeeze in a few different commercials, the number of zones they could cover would be tiny compared to the number of zones available to advertisers via cable systems in the DC market, Maryland, et al.

I did! That is how the OTT service discovers what you want to see. They present you with, say, three possible ads to watch, and have you pick one. From that, theoretically they can figure you out. Or another option is that they ask, with each ad, whether it is of interest to you. Becomes a nuisance fast, is my point.

Who is doing this? Not cable.

I have NEVER been asked to select an ad via any OTT service. That being said, some service do require registration, which gives them at least zip code accuracy. Most of the ads I see are generated based on data collected by search engines like Google. For example we started looking for a used Infinity, and I started to see a very high percentage of Infinity ads.

It's a super risky game to be playing, to change the one-way broadcast standard at this point, IMO. Reason being, there aren't a whole lot of programs that really benefit from a one-way pipe, now that 2-way pipes are already deployed. For instance, all local broadcasters could share, say, a single multiplex in any given market, for that content that really must be live and one-way, and that a huge segment of the population of the market really wants to see. Political maneuvering can change this, however IMO this is the technical reality of today. So changing the OTA broadcast standard will force the FCC to go through all of this, all over again.

Not if they get smart and let broadcasters determine how they want to work together to utilize the spectrum. I would agree that there is little consensus among broadcasters about these issues, but the pending spectrum auction deadline may drive some action. I expect this to be a major topic of discussion at NAB this year...

It might even be time for another Open DTV forum...


 Moving to a network of COFDM (and LTE?) transmitters ads the ability to
 zone advertising by default.

No, actually it doesn't. If you use SFNs, the signal has to be identical from each tower, Otherwise, you will create dead interference zones during ad breaks. That's unavoidable.

That is only one of many potential deployment schemes. Saturating the entire market with the same signal on one channel is what we are moving AWAY from. You can also checkerboard your channels so that each zone is independent. And if you build the system properly, there should be adequate bandwidth to support the carriage of multiple commercials during breaks. The key here is sharing infrastructure, rather than each station running one 6 MHz chunk.

With LTE, same thing exactly, unless you mean that you're using unicast vs broadcast. Unicast requires a 2-way pipe.

This can easily be done with broadcast LTE. You need to stop thinking in terms of individual channels (streams) and start thinking in terms of how websites are created from multiple servers. Most internet ads are not hosted by the website you are looking at; for that matter, most of the video streams are not hosted by these sites either. You can embed ads from any server, lust like you can embed a YouTube video in your site.

What is important here is that you architect the new broadcast system properly to leverage the same tools that the rest of the world is using. Broadcast is just another pipe that can leverage the resources of the Internet.


You can UNSUBSCRIBE from the OpenDTV list in two ways:

- Using the UNSUBSCRIBE command in your user configuration settings at FreeLists.org
- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word 
unsubscribe in the subject line.

Other related posts: