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Old 12-11-2011, 04:47 PM   #1
qz3fwd
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SDV: Symptom Of Useless Channels Or Bandwidth Savior?

So, it seems that the need/desire for some cable companies to implement SDV is a result of several possible market/regulatory failures:

0. With some/many cable companies elimenating analog altogether, is there really a need for SDV????

1. Bundling of channels into packages. Most consumers only watch a small subset of the channels they pay for, and therefore subsidize the small minority of viewers watching the "others". Ala Carte would kill off quickly those "other" channels or the folks which actually watch them would have to fund the development of them. OTOH the programmers would have to survive on the income from the subset of the market which opts to actually pay for their content. If there are that few people actually watching the channels on SDV, then those channels would likely not be financially viable if left to fend for themselves? Maybe the FCC should let a free market determine which channels survive or not & ban SDV altogether?

2. Deterrent by the cable companies for consumers to use their own hardware and not lease cable company provided devices. In other words, make it as painfull as possible to discourage consumers from owning their own hardware. You know-send out scarry misleading letters to consumers that they will lose service if they dont lease cable company provided STB's/DVR's.

3. Unwillingness of cable operators to invest in and maintain their networks. Lack of any real competition in most locales allows the cable companies to sit back, constantly raise prices, and treat subscribers with contempt all the while taking forever to enhance their networks. The use of SDV is a symptom of the cheap way out of this situation.

Any others I missed?

Alternatively, is SDV the savings grace for the cable companies that will provided an almost unlimited selection of channels? Isnt SDV basically identical to services like netflix/amazon except it is served over a network only accessible to the cable companies? What happens to a channel which becomes too popular on SDV and starts using too much bandwidth? Does this channel then get moved to a regular linear always on channel? For example, if there are 500,000 subscribers watching a SDV channel at the same time, would it not be more efficient to move the transport stream to non-SDV? I mean 500,000 x 12 mbps bandwidth versus 12 mbps to everyone in the regular mux? Maybe I misunderstand SDV?
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Old 12-11-2011, 05:25 PM   #2
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Originally Posted by qz3fwd View Post
For example, if there are 500,000 subscribers watching a SDV channel at the same time, would it not be more efficient to move the transport stream to non-SDV? I mean 500,000 x 12 mbps bandwidth versus 12 mbps to everyone in the regular mux? Maybe I misunderstand SDV?
No, you misunderstand SDV. With SDV, all the channels are transmitted over fiber from the headend to the node. At the node, however, only the switched digital channels requested by a subscriber are "turned on." When they are turned on, they are turned on to all homes connected to that node.

It's not a unique "unicast" stream for each subscriber; it is a broadcast stream for everyone on the node. In other words, it's either 12 MBps, or nothing.
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Old 12-11-2011, 05:41 PM   #3
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How many subscribers are usualy connected to one node?
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Old 12-11-2011, 05:55 PM   #4
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Both really, but heavier to the bandwidth problem.

My observation, is at this time, providers are going to SDV to virtually add bandwidth, or removing analog to add more digital channels.

SDV is not like Netflix/Amazon. The VOD service most providers offer os a more apt analog to online content. SDV, BTW, use the same platform as VOD, except SDV has "live" channels, rather than locally stored content.

As for if a channel becomes popular enough, they will move it off SDV, possibly pulling
channels off linear cable to make room.

ETA: Loadstar has the fundamentals of SDV. If one terminal on your node selects an SDV channel and it gets switched in, anybody else that chooses to select that channel at the same time, will tune that same placement, which will stay as long as somebody is reasonalby tuned to that channel.
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Old 12-12-2011, 05:24 AM   #5
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How many subscribers are usualy connected to one node?
The number could vary widely from a few hundred to over a thousand.

A well designed system will be determined mostly by the number of broadband subscribers, not necessarily by video subscribers. Less than 500 broadband subscribers is a good number, any more and the provider should be looking into doing a node split. My particular node has just less than 200 broadband subscribers.
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Old 12-12-2011, 09:06 AM   #6
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No, you misunderstand SDV. With SDV, all the channels are transmitted over fiber from the headend to the node.
Apparently you are the one who has no a flawed understanding of SDV. This is completely false. First of all, the fiber node is nothing but a media converter witth an amplifier. (Well, actually at least two media converters and typically several amplifiers.) It has no swithing capabilities, at all. The switching occurs at the headend or hubsite.

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At the node, however, only the switched digital channels requested by a subscriber are "turned on."
Once again, false. It's not a matter of turning anything on. The carriers are fixed. The bitstreams, however, are switched by a host controler.

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When they are turned on, they are turned on to all homes connected to that node.
If you mean that every home on the node receives the same information, then that is correct.

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It's not a unique "unicast" stream for each subscriber; it is a broadcast stream for everyone on the node. In other words, it's either 12 MBps, or nothing.
I don't know where you got that number. Each QAM delivers 38Mbps. Some number of channels share that bandwidth. This is true whether the QAM is SDV or linear.

Last edited by lrhorer : 12-13-2011 at 07:13 AM.
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Old 12-12-2011, 09:07 AM   #7
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Is there an easy way for me to tell how many broadband subscribers are on my node?

You could say that bundling channels into packages means that one or two desired channels in that package subsidize the other channels. In the same way you could say one or two desired programs on a channel subsidizes the rest of the programs on that channel -You have to purchase the channel to get the programs you want.
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Old 12-12-2011, 10:49 AM   #8
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So, it seems that the need/desire for some cable companies to implement SDV is a result of several possible market/regulatory failures:
Nope, not even a little bit.

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Originally Posted by qz3fwd View Post
0. With some/many cable companies elimenating analog altogether, is there really a need for SDV????
Is there a need for TV at all? Television is most certainly a luxury, and could be eliminated altogether without a fundamental failure of any critical services. The demand for TV services is growing rapidly, however.

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1. Bundling of channels into packages.
That has nothing to do with SDV. What's more, regularly scheduled programming only represents a very small fraction of the total bandwidth of a fully developed SDV system. Video On Demand, IPPV, interactive services, and trick-play features such as "Start Over" make up the bulk of the bandwidth on an aggresive SDV deployment. It also means the cost of deploying any individual stream plummets. Already it is becoming practical for a large company to lease their own SDV channel. In the near future, it will be practical for small companies and even clubs to lease their own channel. Your local bowling league, rod & gun club, SCUBA club, or gardening club will easily be able to afford their own channel. The remainder of your point is completely specious.

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2. Deterrent by the cable companies for consumers to use their own hardware and not lease cable company provided devices.
That is a much more complex situation - admittedly much of it the CATV companies' fault - than you address here. The impetus for the CATV companies to deploy SDV has a vanishinly small component related to any additinal recevues from leasing their devices, especialy since most MSOs make almost nothing directly from their leasing of STBs and DVRs. As to issues relating to 3rd party devices' inability to handle SDV well, that issue rests entirely with the 3rd party manufacturers and the FCC. It was the CE manufacturers that demanded the FCC force CableLabs to produce and support a UDCP specification. It was the CE manufacturers that did not want to be forced to support 2-way and interactive protocols, and the FCC that caved in to them. I'm not saying the CATV companies are blameless in all this - far from it - but the fact subscriber owned equipment doesn't work well with SDV is entirely the fault of the CE manufacturers and the FCC.

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3. Unwillingness of cable operators to invest in and maintain their networks.
You haven't even the slightest clue. MSOs have invested nearly $20 Billion in upgrading their systems, including deploying SDV. Also, you evidently have no idea what goes into upgrading a CATV system. For a comparatively modest investment in SDV, the CATV system can create a system literally capable of delivering an infinite number of channels, with unlimited growth potential for very modest additional outlays in cash. That, or for ten to fifty times as much money, they can increase their number of channels by 125, with zero growth potential.

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Any others I missed?
I'm waiting for you to come up with a single valid one.

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Alternatively, is SDV the savings grace for the cable companies that will provided an almost unlimited selection of channels?
Not "almost". In a properly engineered SDV system, there is no upper bound to the number of "channels" that can be deployed.

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Isnt SDV basically identical to services like netflix/amazon except it is served over a network only accessible to the cable companies?
No, it's much closer to being very much like RoadRunner, AT&T, or Verizon Internet service. It's a transport mechanism, not a content provider.

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What happens to a channel which becomes too popular on SDV and starts using too much bandwidth?
There is no such thing. First of all, if one channel gains in market share, then without fail some other channels will lose the same amount of market share. If a really large shift in popularity occurs, then hypothetically that channel might become better served by a linear QAM, and the CATV company can decide to move it to one such QAM, or not. The most popular Big Band digital modulator serves 8 QAMs, which can represent 16 HD channels and 2 SD channels. Six such modulators can serve the 96 most popular HD channels and the 48 most popular SD channels, or perhaps the 90 most popular HD channels and 81 most popular SD channels. That uses up 360 MHz. Let's assume the CTV system is delivering 90 HD channels on that spectrum, and for simplicity's sake, let's forget about SD for the moment. Now, perhaps you haven't noticed, but more than 80% of the viewing bandwidth is serviced by a mere 10 channels, leavng 80 channels to service no more than 20% of the viewing palate, with the remainder being outside the linear coverage. For argument's sake, however, let us assume over time the national networks no longer have a headlock on the viewing public, however, and the viewing coverage among the top 90 channels is nearly even. This is the worst-case scenario in terms of your proposed situation. In this case, no channel outside those 90 can possibly have a penetration of greater than 1.1%. The actual number is much lower. With a penetration of less than 1.1%, there is a fair chance any given node may not need to broadcast that stream, allowing the bandwidth to be used for some other stream. If some channel other than those 90 gains enough popularity to require more than 1.1% of the bandwidth, then it must be true that at least one of the original 90 now has a popularity of less than 1.1%, and can be moved to SDV, while the newly popular channel moves over to the linear system. 'No big deal, really.

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Does this channel then get moved to a regular linear always on channel?
That's up to the CATV provider. Since they purchase modulators that host significant numbers of streams at a time, micro-managing the lineup is probably more trouble than it is worth for them. To the user, however, it is largely transpartent.

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For example, if there are 500,000 subscribers watching a SDV channel at the same time, would it not be more efficient to move the transport stream to non-SDV? I mean 500,000 x 12 mbps bandwidth versus 12 mbps to everyone in the regular mux? Maybe I misunderstand SDV?
First of all, it depends on how many subs (actually, tuners, not subs. Most subs have more than one tuner) there are, total. What's more, it doesn't even depend on that. SDV relies upon its gains for a significant number of nodes to not have any users watchihng a channel for a significant period during the day. Here in San Antonio, for example, there are many neighborhoods on the East side of town that have predominantly Black residents, while on the West side there are large areas that are almost all Latin. Both BET and Galavision are fairly popular channels here, but there is a very good chance that a large number of nodes on the East side will not have even a single viewer watching Galavision while on the West side, there will be many nodes without a single viewer watching BET. On the North side of the city, there are probably a fair number of nodes that at the very same moment have neither channel on them.

The bottom line: Here in San Antonio, there are some 300 SDV channels. Of that number, there are only about 60 from which I ever record at all, and only about 30 from which I record regularly. That may sound terribly limited, but then consider the non-SDV channels from which I record - all seven of them - and that in all but 2 cases much less than any of the 30 SDV channels from which I regularly record.

Last edited by lrhorer : 12-12-2011 at 12:05 PM.
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Old 12-12-2011, 11:32 AM   #9
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How many subscribers are usualy connected to one node?
That is an engineering / accounting decision on the part of the CATV company, and varies a lot from company to company , or even city to city. Most MSOs design their plant so that the service from a node passes between 400 and 1000 dwellings. Typical penetrations run from about 40% to about 70% in most neighborhoods.

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Old 12-12-2011, 11:39 AM   #10
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Is there an easy way for me to tell how many broadband subscribers are on my node?
Broadband subs, or CATV subs? The latter, no. The fomer, one can sniff the ARPs coming down the pipe and make an estimate.

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Originally Posted by matt@thehickmans View Post
You could say that bundling channels into packages means that one or two desired channels in that package subsidize the other channels. In the same way you could say one or two desired programs on a channel subsidizes the rest of the programs on that channel -You have to purchase the channel to get the programs you want.
That's right. Unless the company moves to a 100% IPPV model, where one purhcases each individual program independantly, there is always going to be some level of granularity below whihc subsidies exist. That said, I dearly would love to be able to shed the cost of the national networks and such things as ESPN, TBS, etc. I have no desire to watch them and less desire to pay for them.

Last edited by lrhorer : 12-12-2011 at 11:48 AM.
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Old 12-12-2011, 11:56 AM   #11
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ETA: Loadstar has the fundamentals of SDV. If one terminal on your node selects an SDV channel and it gets switched in, anybody else that chooses to select that channel at the same time, will tune that same placement, which will stay as long as somebody is reasonalby tuned to that channel.
Correct, with the clarification that "at the same time" does not mean they have to request the channel at the same moment. Rather, if a stream is already extant and an additional sub requests that same stream, then their equipment is simply directed to tune to the existing stream. If, however, one sub is ten minutes into watching a VOD offering and a second sub requests the same movie, then a second stream on a different timeslot and probably even a diferent QAM will be initiated from the beginning. The same is true of special features like "Start Over". If a sub on TWC requests "Start Over" on a program on ABC, NBC, Fox, whatever, then the headend will spawn a separate stream for that program starting from the beginning, the fact the main channel is on a linear QAM notwithstanding.
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Old 12-12-2011, 02:20 PM   #12
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The number could vary widely from a few hundred to over a thousand.

A well designed system will be determined mostly by the number of broadband subscribers, not necessarily by video subscribers. Less than 500 broadband subscribers is a good number, any more and the provider should be looking into doing a node split. My particular node has just less than 200 broadband subscribers.
Perhaps Cable subscribers could start an "Occupy" movement to cause the self destruction of SDV.

Have as many subscribers on one node as there are cable channels all select a different channel then have those who don't get their channel call to complain.
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Old 12-12-2011, 02:49 PM   #13
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A well designed system will be determined mostly by the number of broadband subscribers, not necessarily by video subscribers. Less than 500 broadband subscribers is a good number, any more and the provider should be looking into doing a node split. My particular node has just less than 200 broadband subscribers.
SDV has nothing to do directly with broadband service. The number of broadband subs and the number of homes passed are not the same thing, although 200 subs is about right for a typical neighborhood with about 450 - 500 homes passed. Only about half, give or take, of homes have CATV service in a typical neighborhood, and only some large fraction of CATV subs have broadband service.
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Old 12-12-2011, 03:51 PM   #14
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You don't understand, we need 37 different channels showing re-runs of the various flavors of CSI and Law and Order.

Not to mention all of those "common people being common, even if they're rich" reality shows that must run 'round the clock.

Just like we need for everyone to have to subsidize ESPN, whether they give a sh*t about sports or not, otherwise ESPN might not be able to take the big sports events (like when local favorite teams are in NCAA March Madness) away from your local free OTA channels.
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Old 12-12-2011, 06:21 PM   #15
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Apparently you are the one who has no understanding of SDV.
I would say, despite the apparent error of where the switching occurs, the basic fundamentals of my explanation are more correct than the OP's. I wouldn't say that I have "no understanding" of SDV.
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This is completely false. First of all, the fiber node is nothing but a media converter witth an amplifier. (Well, actually at least two media converters and typically several amplifiers.) It has no swithing capabilities, at all. The switching occurs at the headend or hubsite.
My error. I was going based on the information on Wikipedia, as unreliable as Wikipedia might be. Perhaps you might be generous enough to revise the page?
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Once again, false. It's not a matter of turning anything on. The carriers are fixed. The bitstreams, however, are switched by a host controler.
When I said "channel," I didn't mean the carrier, I meant the bitstream. Sorry to use unclear language. (I was speaking in the colloquial, as most would refer to the "channel" as the video content you watch.)
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I don't know where you got that number. Each QAM delivers 38Mbps. Some number of channels share that bandwidth. This is true whether the QAM is SDV or linear.
I was continuing with the same hypothetical number that the OP used. I didn't take the time to research whether that number was correct or not.

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Old 12-12-2011, 06:43 PM   #16
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Perhaps Cable subscribers could start an "Occupy" movement to cause the self destruction of SDV.
I hope not. Time Warner Cable does it right in NC. Almost every single channel is on SDV. It is part of the reason why we have so many HD channels compared to other TWC areas and other cable companies. I think we have around 110-120 HD channels (not counting VOD options).

And there are very little issues with SDV anymore. TWC here is good about updating tuning adapters and cablecard firmware (it happens every few weeks it seems).
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Old 12-12-2011, 07:00 PM   #17
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I hope not. Time Warner Cable does it right in NC...
Unless you're one of their analog customers* whose number of channels keeps going down and whose bill keeps going up.

*who still has lots of analog equipment that's working just fine so why spend money replacing it?
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Old 12-12-2011, 08:28 PM   #18
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In my city, they dumped all the analog programming and went full digital. This leaves enough bandwidth to run all of the HD programming without SDV. The only analog channel left runs information 24/7 telling you that you need a box to watch TV. I have no idea if any of the channels are clear QAM, since I only use TiVos to watch TV. For those people with analog equipment, where do you buy Beta tapes anyway? It's 2011, not 1989.
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Old 12-12-2011, 08:36 PM   #19
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In my city, they dumped all the analog programming and went full digital. This leaves enough bandwidth to run all of the HD programming without SDV. The only analog channel left runs information 24/7 telling you that you need a box to watch TV. I have no idea if any of the channels are clear QAM, since I only use TiVos to watch TV. For those people with analog equipment, where do you buy Beta tapes anyway? It's 2011, not 1989.
Twenty years after 1989, i.e., only 2 years ago, television was still broadcast in gracefully degrading analog before being replaced by all or nothing digital.
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Old 12-12-2011, 08:53 PM   #20
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General Instrument showed the first digital cable boxes in 1989. And DirecTV launched in 1994 with completely digital programming. It's not like digital TV is new.
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Old 12-12-2011, 08:59 PM   #21
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General Instrument showed the first digital cable boxes in 1989. And DirecTV launched in 1994 with completely digital programming. It's not like digital TV is new.
No, it's only having it rammed down our throats that's recent.
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Old 12-13-2011, 12:00 AM   #22
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I don't know where you got that number. Each QAM delivers 38Mbps. Some number of channels share that bandwidth. This is true whether the QAM is SDV or linear.
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I was continuing with the same hypothetical number that the OP used. I didn't take the time to research whether that number was correct or not.
As a followup thought/observation: as you note, lrhorer, the 38Mbps (approximately) is divided between multiple sub-channels (a.k.a. bitstreams). Each sub-channel (bitstream) will have varying bitrates, of course, depending on the kind of content on the channel, and whether the cable system opts to re-encode the channel (bitstream) at a lower data rate.

That said, from what I understand based on multiple other references I have consulted, an average bitrate of 12 MBps for an HD channel is somewhat low, but not unheard of these days. A relatively recent sampling of data rates indicates that AMC HD is on the very low end, at an average of about 8 Mbps average, while A&E HD has somewhere around 17 Mbps average bitrate. (14-16 Mbps is probably a more "typical" average bitrate here... although more bandwidth starved cable systems will probably be in the 12 Mbps rage.)

Therefore, the OP (and I) weren't wrong to use 12 Mbps as a hypothetical number, as it could reflect the bitrate for what would be an HD channel on a contemporary cable system.

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Old 12-13-2011, 05:55 AM   #23
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You don't understand, we need 37 different channels showing re-runs of the various flavors of CSI and Law and Order.
Most of the channels of which you speak are not usually SDV. The bulk of the channels - by nearly a factor of 10 - from which I record are.

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Not to mention all of those "common people being common, even if they're rich" reality shows that must run 'round the clock.
Once again, most of those channels are not SDV on most systems.

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Just like we need for everyone to have to subsidize ESPN, whether they give a sh*t about sports or not
I happen to agree. I have no interest in any of the flavors of ESPN or its relatives. The people who are should pay for them, not me. The question at hand is not, "Who should pay for them?", but rather, "Should they exist?" As long as the people who want ESPN and its two dozen or so relatives pay for them, their existence is both desirable and ethical. SDV makes it practical.

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otherwise ESPN might not be able to take the big sports events (like when local favorite teams are in NCAA March Madness) away from your local free OTA channels.
OTA channels are NOT FREE!!!!. They are exceedingly expensive, and what's more they are much more aggressive examples of forced subsidization than any bundled CATV channels. They also happen to be of absolutely no interest to me.

The point here is, what constitutes a "useless" channel? The fact you find it useless does not mean someone else does. I agree if you are not interested in watching them, then you should not have to pay for them, but then the same is true of the local channels. I am forced to pay on the order of $10,000 a year or more for the OTA channels, and I neither want them nor watch them. Someone else should pick up that tab. Of the roughly 70 channels from which I record on any regular basis, only 1 (PBS) is available OTA.
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Old 12-13-2011, 06:16 AM   #24
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I would say, despite the apparent error of where the switching occurs, the basic fundamentals of my explanation are more correct than the OP's. I wouldn't say that I have "no understanding" of SDV.
Well, OK.

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My error. I was going based on the information on Wikipedia, as unreliable as Wikipedia might be. Perhaps you might be generous enough to revise the page?
There is nothing on that page to suggest the switching occurs at the node. Switching occurs, oddly enough, at the switch, which resides in the hubsite, right before the modulator. The output of all the modulators are combined into the full spectrum you see at the back of your receiver, which is in turn converted to an optical signal that is then sent over a fiber strand to the node, which converts the signal back from optical to electrical.

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When I said "channel," I didn't mean the carrier, I meant the bitstream. Sorry to use unclear language. (I was speaking in the colloquial, as most would refer to the "channel" as the video content you watch.)
The bitstream isn't turned on and off, either. It's a constant 38Mbps. What happens is the payload is switched to different sources as required. The "channel" exists as a timeslot within the bitstreram, but even if the "channel" goes away, the bitstream and its timeslots still exist, they just no longer carry that particular video. Even if the timeslot is idle, it's still there.
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Old 12-13-2011, 06:21 AM   #25
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Unless you're one of their analog customers* whose number of channels keeps going down and whose bill keeps going up.

*who still has lots of analog equipment that's working just fine so why spend money replacing it?
That's the exact same logic a classmate of mine offered in 1976 when I asked him why he continued to purchase 8-track tapes. The term, "Just fine" rests upon a definitin many of us no longer find acceptable.
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Old 12-13-2011, 07:03 AM   #26
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Twenty years after 1989, i.e., only 2 years ago, television was still broadcast in gracefully degrading analog before being replaced by all or nothing digital.
So rather than make sure the delivery system is functioning properly, you prefer to rely on a system that tolerates it being broken?

It's true analog signals usually degrade gracefully, while digital signals do not. It is also true that degraded analog signals can be often be captured below the point where digital signals fail. OTOH, this is the only significant advantage analog transport has over digital. While analog signals continue to be recoverable longer, they also degrade much sooner. Long after an analog signal will be adjudged "poor" by most viewers, digital signals are still 100% perfect*.

Analog signals eat up a lot of bandwidth. In the same bandwidth used by a single analog NTSC video, broadcasters can deliver as many as 12 SD videos of quality superior to the analog video. What's more, HD video completely blows most analog video right out the door, and is far superior to even the best digital SD video.

There is also a more fundamental relationship here. Until the 1990s, CATV systems universally delivered their signals to the customer over a completely coaxial cable system. Depending upon the subscriber's distance from the hubsite, the signal may have passed through as many as 30 amplifiers, or in some cases even more. Not only did each amplifier add its own bit of noise and distortion to the signal, but each amp added some level of instability to the overall system gain. Although most of the outdoor amplifiers had thermal compensation or else active Automatic Gain Controls, the signal levels still varied a lot over time. Maintaining constant signal levels was literally a daily chore for the maintenance technicians, and it was often a losing battle. At the furthest points from the headend, signal levels, noise, and distortion were often right on the ragged edge between acceptable and unacceptable, and any little thing could and sometimes regularly would push them over the line. The long cascades also presented a huge number of points of potential failure. Some failures, of course, would kill the signals altogether, but many failures would merely cause increased levels of interference, noise, or distortion.

With the advent of digital delivery systems, however, the CATV systems deployed a new transport strategy: optical fibers. In an optical fiber transport system, there are no longer many miles long cascades of amplifiers and coaxial cable. Instead, a single strand of optical fiber carries the signals from the headend to a node within less than a mile from the subscriber's house. There it hits the fiber node, and then at most 2 additional amplifiers. Not only are noise and distortion greatly reduced, but signal stability is vastly enhanced. The result is while signals do still vary in quality with time, they no longer usually exceed the recovery limits of digital systems over relatively long periods of time. This means it is possible for the maintenance staff to actually achieve near 100% reliability of the digital transport system. Problems do of course still surface, and over long periods of time the system still needs to be tweaked back into spec, but the PQ can now be consistent on a scale not possible with any analog system. It also means the vast majority of failure points have been eliminated entirely.

* - "Perfect" meaning the recovered bitstream is identical to the one transmitted from the source.
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Old 12-13-2011, 07:09 AM   #27
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General Instrument showed the first digital cable boxes in 1989. And DirecTV launched in 1994 with completely digital programming. It's not like digital TV is new.
Not only that, but digital video long predated 1989. Digital transport systems were developed in the late 1970s for delivering video to video providers such as TV stations and mobile broadcast links.
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Old 12-13-2011, 07:33 AM   #28
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In my city, they dumped all the analog programming and went full digital. This leaves enough bandwidth to run all of the HD programming without SDV.
Define "All". It is true if one limits ones' system to liner video only - no VOD, IPPV, or interactive services of any sort, then a 750MHz CTV system can deliver all the linear HD services avalable today. Specifically, a 750MHz system has about 678 MHz or so of bandwidth up for grabs. That equates to 113 QAM carriers. With industry norm rate shaping, that results in 226 HD channels with 113 SD channels. This is indeed a bit more than enough to deliver just about all the nationally available linear HD video sources... at this time. It won't be long, however, before the number of available HD video sources is much greater than this. It also allows nothing for VOD and very little for IPPV channels. Of course, by upgrading to 860 or 1000Mhz, one can add a significant number of channels, but one is still limited to a very finite number of channels, and this and any subsequent upgrades are hideously expensive. At some point, bandwidth upgrades are not even possible. By comparison, a 750 MHz CATV system with 200MHz of analog channels, 250 MHz of linear digital QAMs, and 200MHz of SDV QAMs can potentially deliver thousands of video channels for a fraction of the cost of upgrading from 750 MHz to 1000MHz.
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Old 12-13-2011, 08:08 AM   #29
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Define "All".
There is a single analog channel. This channel runs a 24/7 banner stating that you need a box to watch any TV. There is no analog programming whatsoever. No locals, no basic, no nothing. They shipped out free mini-boxes to anyone who had an analog set. I had my cable set up with one of their DVRs, and five TiVo boxes using CableCards. I only found out that the analog channels were shut off when I hooked up an old Series2 box to see if it worked.
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Old 12-13-2011, 10:37 AM   #30
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......... I am forced to pay on the order of $10,000 a year or more for the OTA channels.......
How do you figure that? The per-capita GDP for the U.S. was around $47,000 per person in 2010. (See **this reference** and pick the exact number you like.)

No question there is taxpayer subsidization of OTA broadcasting and indirect support via advertising costs hidden in purchases. But there is no way it can average $10,000 per person, since that would be 21% of our GDP. If you assume $10,000 per average taxpayer (about 143 Miillion returns filed in 2010, http://www.census.gov/compendia/stat...es/12s0481.pdf) the number is still about 10% of GDP -- still ridiculous. Assuming you could back this number up for your particular situation, i.e., based on your taxes and your purchases, it sure isn't representative of most folks.

For other readers, this is a new version of the same kind of ridiculous claim that lrhorer has made in a number of threads here -- and never backed up.
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