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SDV FAQ

Discussion in 'TiVo Series3 HDTV DVRs' started by bdraw, Jul 3, 2007.

  1. morac

    morac Cat God

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    That's actually already being done. There are a number of programs on Comcast's VOD that are only available through VOD.
     
  2. MichaelK

    MichaelK New Member

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    without getting into politics- 2 words

    Howard Stern.

    Isn't his "howard TV channel" all vod?

    I think VOD is a way for people to create new niche "channels". Maybe they wind up SDV when SDV is widely deployued- but for now VOD lets such a thing exist.
     
  3. May 1, 2008 #1463 of 2401
    lrhorer

    lrhorer Active Member

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    Virtually no one offers VOD unless it's SDV. It would be network suicide to do so, even on a small scale. I don't know for certain - sometimes businessmen do stupid things, but I strongly suspect there are no CATV systems anywhere which offer anything as VOD which is not SDV. Some systems may offer Howard as linear pay-per-view, in which case it would not have the network impact of a linear VOD channel, but there's a big difference between linear IPPV and non-SDV VOD.
     
  4. May 1, 2008 #1464 of 2401
    vstone

    vstone New Member

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    So you're saying that since almost everywhere has VOD, almost everyone has SDV and a complete SDV infrastructure is in place almost everywhere. Pardon my skepticism.
     
  5. May 1, 2008 #1465 of 2401
    jrm01

    jrm01 New Member

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    Far, far from the truth.
     
  6. May 1, 2008 #1466 of 2401
    ah30k

    ah30k Active Member

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    Wow, how far wrong could this statement be?

    Since SDV is just getting launched, are you saying no one had any VOD prior to now?

    Maybe there was just a mis-use of terms or something but you couldn't have meant what it seems.
     
  7. May 1, 2008 #1467 of 2401
    cableguy763

    cableguy763 New Member

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    Irhorer is correct. Most VOD systems use 4 qams for VOD delivery. The VOD system and cable box determine which qam is available and starts the stream. You can start 4 different movies in a row and have it stream on 4 different frequencies. This system has been around for a long time.
     
  8. May 1, 2008 #1468 of 2401
    ah30k

    ah30k Active Member

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    When we refer to SDV we are talking about the system just being launched that switches broadcast video. While it is true that VOD dynamically gets assigned to QAMs, we really don't call that SDV.

    Hence my claim that this may just be a miscommunication of terms.
     
  9. May 1, 2008 #1469 of 2401
    cableguy763

    cableguy763 New Member

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    True. Not SDV, but very similar in their most basic functions.
     
  10. May 1, 2008 #1470 of 2401
    mikeyts

    mikeyts Stream Warrior

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    What lrhorer is saying is that VOD is a form of switched video which has been in use far longer than this fairly new "sharing-a-pool-of-bandwidth-on-a-network-edge-segment-between-many-linear-video-services" trick. No doubt modern systems use switching to implement scheduled pay-per-view as well--if no one in an edge segment has ordered a pay-per-view program, no bandwidth is used for that program on that segment. However, referring to VOD and IPPV as SDV, while it may be essentially true, is cheap semantic BS. The terms "switched video" and "switched digital video" are now exclusively used to refer to the "sharing-a-pool-of-bandwidth-on-a-network-edge-segment-between-many-linear-video-services" trick. When you find SDV in the tech literature today, that's what they're talking about, even though VOD and IPPV are provided using video switching. Maybe they should have come up with a brief three-or-four word phrase to describe "sharing-a-pool-of-bandwidth-on-a-network-edge-segment-between-many-linear-video-services" (maybe "shared bandwidth linear video", though that would describe IPPV as well :rolleyes:), but the fact is that they didn't--they co-opted the term "switched digital video" to mean specifically that.

    It's similar to the way that, when people refer to "Americans" in common speech, they're talking about citizens of the United States of America, and not Canadians or Mexicans or Brazillians, even though those people also live on the continents of North and South America.

    The discussion in this thread is about "non-PPV shared bandwidth linear video", the increasing use of which is a large problem for TiVo Series3 and TiVo HD users, who never expected to be able to access VOD or IPPV content with TiVo. Using the term "SDV" as an umbrella term for all services which involve video switching doesn't make any useful point and only serves to confuse the conversation and annoy people.
     
  11. May 1, 2008 #1471 of 2401
    ajwees41

    ajwees41 Active Member

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    Cox Omaha offers vod and doesn't have sdv yet.
     
  12. May 1, 2008 #1472 of 2401
    Firekite

    Firekite New Member

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    Doesn't have or hasn't yet implemented for network channels? There is a difference...
     
  13. May 1, 2008 #1473 of 2401
    ajwees41

    ajwees41 Active Member

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    what is the differnce? Omaha has had ondemand since last year and doesn't use sdv.
     
  14. May 1, 2008 #1474 of 2401
    mikeyts

    mikeyts Stream Warrior

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    Read my last post above. VOD is a form of switched video, but no one today is referring to VOD when they say "switched digital video" (except lrhorer :)).
     
  15. May 1, 2008 #1475 of 2401
    dswallow

    dswallow Save the ModeratŠ¾r TCF Club

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    The main difference is that SDV is coordinated between multiple viewers so each can simultaneously view the stream and there's no interactive control possible. VOD is exclusively viewed, only the customer who started the stream can view the stream and usually has the ability to interactively control the stream.
     
  16. May 1, 2008 #1476 of 2401
    morac

    morac Cat God

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    While functionally that's they way it's supposed to work, there are exceptions. At times I've stumbled across VOD streams (which for whatever reason weren't encrypted) using the QAM tuner on my TV. Granted I couldn't control the playback, but I could still view it.

    It did throw me the first time I saw a movie "rewind itself" while watching TV. :)
     
  17. May 1, 2008 #1477 of 2401
    dswallow

    dswallow Save the ModeratŠ¾r TCF Club

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    That's just lack of encryption by the cable company, though.
     
  18. May 1, 2008 #1478 of 2401
    morac

    morac Cat God

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    What's weird is that my cable company is extremely anal about encryption. Everything except broadcast channels (and VOD streams) are encrypted. So the only things I can get via clear QAM is CBS, NBC, ABC, PBS, CW and VOD. :)
     
  19. May 1, 2008 #1479 of 2401
    MichaelK

    MichaelK New Member

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    different encryption -

    the CCI bits that the idiots are setting for you to block everything are not the same sort offlags that they use in their non-cablecard systems. Since VOD isn't cablecard I'd guess there's no way to set the CCI bits at all. There's probably some other setting which they are forgetting.
     
  20. May 1, 2008 #1480 of 2401
    morac

    morac Cat God

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    The CCI bits for all but the premium channels are 0x00 on my cable system such that I can transfer most shows off my TiVo, but the channels are still encrypted so that a cableCARD (or cable box equivalent) is needed to receive the channel.

    I'm not sure if this is technically called encryption or subscription. Either way they won't show up in clear QAM.

    I'm pretty sure VOD also uses CCI bits since VOD is supposed to be tagged with CCI=0x03.

    You are right though, they probably forgot to set something up.
     

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