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SDV FAQ

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

  1. Dec 27, 2007 #921 of 2401
    Luke M

    Luke M Member

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    Nov 5, 2002
    The problem with the BroadLogic idea is that it's as expensive as providing every TV with a set top box. So the only advantage is whatever customer satisfaction is obtained from allowing people to continue with their old habits.

    An alternative gateway approach would be to provide a limited number of simultaneous analog channels, like 4. For each analog TV you would have an RF remote control to select the channel. This might be a little cheaper than a set top box for each TV.
     
  2. Dec 27, 2007 #922 of 2401
    lrhorer

    lrhorer Active Member

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    Hypothetically this would be possible if the entire QAM is devoted to non-switched channels, but in practice it's not practical. It costs as much to segregate the topology of the headend or hubsite into two sections with different topologies than to simply deploy a single topology for the entire site, and the maintenance and management costs are much lower, not to mention the engineering headaches are greatly reduced. Believe me, designing a headend is difficult enough when all the sources are symmetrical. Adding assymmetrical sources makes things really difficult.

    What's worse, adding a new channel or moving a channel from one tier to another suddenly becomes very difficult and time consuming, requiring potentially many hours of truck rolls and channel down-time. If the same system is used for all digital programming, then adding, deleting, or moving a channel or changing from linear to SDV or vice-versa becomes a matter of a few mouse clicks.

    Not only that, but one of the features which has CATV providers salivating is the prospect of automated channel upgrades. The user tunes to a channel he does not receive, presses a button and viola! he receives and is billed for a month of HBO or Showtime.
     
  3. Dec 27, 2007 #923 of 2401
    mikeyts

    mikeyts Stream Warrior

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    Again, you only need one of these boxes for all of the analog tuners in use in your household. In fact, you could package these things up with amplifiers and put them in the neighborhood distribution boxes, sharing one between several households, selling connections to them as "analog service options" (if you do that, you lose the possibility of selling pay SD digital channel tiers). I don't know about older installations, but the newer homes that I've lived in (built in the past twenty years) have 2-3 lines running in from the those boxes--it'd be simple to connect one or more of them to one of these "gateways" and distribute it to the appropriate outlets.

    I'm also sure that pricing of these chips is falling as fast as BroadLogic can make it happen, isasmuch as they haven't sold any of them yet at that year-ago price.

    Don't belittle the goal of "allowing people to continue with their old habits". It's called not messing with a satisfied customer. Try to force them to use boxes that they don't want to deal with and they'll take a long hard look at whether they need your service at all and what they might do as an alternative.
     
  4. Dec 27, 2007 #924 of 2401
    dswallow

    dswallow Save the ModeratŠ¾r TCF Club

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    I believe the concept is that by eliminating use of bandwidth in the cable plant for any analog signals one no longer needs SDV at all... at least such that the digital channels that would be placed on an analog cable in the home wouldn't be SDV.

    I wonder if that chipset has the power to take HD digital signals and downconvert them to SD, thus further eliminating the need to carry SD channels if they have HD counterparts.
     
  5. Dec 28, 2007 #925 of 2401
    Luke M

    Luke M Member

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    Nov 5, 2002
    That's true, but at the same time, some customers would be happier with the set top box solution and the features it enables (like VOD available on every TV).

    Several factors are gradually decreasing the cost of going "all digital":
    1) Customers voluntarily subscribing to services requiring a STB
    2) FCC tuner mandate having the side effect that almost all new TVs can receive unencrypted QAM
    3) STBs getting cheaper
     
  6. Dec 28, 2007 #926 of 2401
    mikeyts

    mikeyts Stream Warrior

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    Every last one of those customers is pounded with ads from the cable company telling them about the wonderful world awaiting them with a box. I gotta think that most people who haven't chosen to add boxes to their televisions have good and sufficient reasons. My housemate is perfectly satisfied with the 75-80 channels that she can tune from her little 20" television in the LR (expanded basic is included in the HOA fees here) and has no desire for VOD. Many people using analog cable now have televisions placed in locations so that they can watch a sitcom or the news while they prepare a meal or in the rooms of small children where they don't need anything more than PBS and Disney. Some of those have boxes in their family rooms and don't want or need them anywhere else. Some don't have any boxes and the major advantage of cable television for them is the fact that they don't have to buy or lease an STB or learn to use a remote control more complicated than a number keypad with CHAN UP/DOWN, VOL UP/DOWN, ON/OFF. Force them to use an STB and they're not going to be happy with you and they might as well take a look at the pricing of what the satellite and telco folks are offering.
     
  7. Dec 28, 2007 #927 of 2401
    Luke M

    Luke M Member

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    Nov 5, 2002
    Yes, but the reason is not necessarily that they place a negative value on digital. For some, the only problem is that the value is less than the cost.
     
  8. Dec 28, 2007 #928 of 2401
    bdraw

    bdraw Member

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    You're confusing packet switched with circuit switched. It's more like a telephone line (circuit switched) than Ethernet (packet switched). Packet switched would be IPTV, not SDV.
     
  9. Dec 28, 2007 #929 of 2401
    morac

    morac Cat God

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    The bandwidth that would be freed up by dropping Analog is most likely being earmarked for things like faster broadband connections (ie: DOCSIS 3.0). By using SDV and dropping analog and switching to MPEG-4, the cable companies can free up a lot of bandwidth for use for other things. See this article.

    Speaking of MPEG-4, I found this article which describes how using SDV can ease the transition to MPEG-4 (and save bandwidth) by providing MPEG-4 streams to those boxes that support it, but MPEG-2 streams to those that don't. All while keeping the same channel number for both streams. T
     
  10. Dec 28, 2007 #930 of 2401
    jsshattuck

    jsshattuck New Member

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    Charlotte, NC
    GREAT news!!! In October TWC added several new HD channels using SDV (Switched Digital Video--see thread on SDV if you are not familiar with it). Since the TiVo 3 cannot handle SDV, we were either force to do without the new channels or pay $10/month for an STB. Today I visited the TWC website and discovered that one of the channels (Golf/Versus) had been moved to the basic tier. A light went off in my brain that said if that was true, pehaps it was no longer using SDV and could be viewed and recorded by my TiVo. In fact that is true for that channel as well as all the other new HD channels.

    Looks like TWC has seen the light about selecting SDV channels, and at least for now, new HD channels will have dedicated frequencies and will work with CableCARDs.
     
  11. Dec 28, 2007 #931 of 2401
    lrhorer

    lrhorer Active Member

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    There are several different possible SDV implementations. What works best depends upon a number of factors, including the physical size of the geographical area being served, the average number of subscribers per mile of fiber, the bandwidth of the CATV plant, the number of QAM streams, the number of nodes served from the hubsite, and the ratio of SDV bandwidth to linear digital bandwidth. Here in San Antonio they simply use AM fiber, where the entire RF spectrum is just directly AM modulated as a 750 MHz baseband signal onto the LASER. The nodes themselves are not digital. It's by far the least expensive method of getting the signal out to the node, but it also imposes very strict limitations on the maximum distance from the hubsite to the node. I could be mis-remembering, but if I recall the maximum distance to the node for the gear they use here is less than 14 route miles of fiber. Given that 14 route miles may be as little as 7 or 8 line of sight miles, that's not much for a city the size of San Antonio. Still, it works and it's economical.

    Delivery of the digital stream to the hubsite is via pt-pt 10G Ethernet, not an Ethernet ring, although an Ethernet ring would certainly be a possible implementation. The 10G wavelength is carried over a DWDM ring for redundancy, but it is not a ring at the Ethernet layer. Once again, the decision to deliver over pt-pt links rather than a ring is one which is determined by the geographical node density, the number of hubsites, the number of SDV streams, etc.
     
  12. Dec 28, 2007 #932 of 2401
    mikeyts

    mikeyts Stream Warrior

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    In some areas, TWC's plan to use SDV has been combined with their roll-out of their new Digital Navigator IPG, created and maintained in-house. They have both a hard-coded versions called "Mystro Digital Navigator" (MDN--the original codename of the product was "Mystro") which will run on the memory-limited legacy SA boxes and an OCAP version (ODN) which will run on their new CableCARD-using "C" series leased boxes (i.e., SA Explorer 4250C, 4250HDC, 8300C and 8300HDC), all of which have twice the applications RAM of the old ones. The OCAP version can also run on new "CableCARD V2" equipment with OCAP--they and Samsung have been demonstrating it at product shows running on prototype Sammy televisions for the past year or two.

    Digital Navigator has been a bit less than ready-for-primetime; when they rolled it out in trialed in Lincoln, NE last year, it upset so many subs that they held city council hearings to decide whether they had cause to break their contract with TWC and choose a new cable service provider. So, in most places they seem to be taking a slow and cautious approach, distributing ODN on new SA Explorer "C" series boxes but holding off on pushing MDN to everyone with legacy boxes. Even if all the bugs have been worked out, it's gonna be a mess when they push this, with tons of calls from confused subs whose STBs sudden present a different looking GUI with a different set of menus which doesn't respond to quite the same set of commands. Since the "legacy" IPG that they using (Aptiv Digital's Passport and Passport Echo) hasn't been updated to work with the SDV system that they're using, they have to wait until they're ready for widespread deployment of Digital Navigator before they can start using SDV. I think that they'd thought to withhold stuff that they planned to place in an SDV group from their CableCARD customers so they wouldn't have to take them away from them later, but too many people complained.
     
  13. Dec 29, 2007 #933 of 2401
    XBR

    XBR New Member

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    According to this article: http://www.cable360.net/ct/strategy/emergingtech/26402.html, the core transport in SDV is packet-switched IP; IP over 10 GbE, SONET, DWDM, etc. It goes on to mention how packet loss, queuing delays and jitter can impact QoE (Quality of Experience), as with VoIP.

    I believe the term IPTV more generally refers to television-type services delivered over "traditional" data networks...
     
  14. Dec 29, 2007 #934 of 2401
    lrhorer

    lrhorer Active Member

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    No, I'm not confusing them, although I did over-simplify the situation. Actually, SDV is close to being a hybrid of the two types of network. The salient point here, however, is that what happens at layer 2 switching is irrelevant to what happens at layer 3 and above. At layer 2 on an Ethernet network, switching occurs at the packet level whether layer 3 is routed or switched or what the layer 3 service might be. The 802.1 protocols are always circuit-less, whether the layer 3 protocols are circuit-less or not. Since the links being used ARE ethernet, they are not "more like a telephone line (circuit switched) than Ethernet (packet switched)". The San Antonio system uses 10G Ethernet to transport their streams (analog, linear digital and SDV) out to their hubsites.

    The important point in my original post was traffic not needed by the intermediate hubsite is not sent to the hubsite, and traffic not needded by the node is not sent to the node. The traffic links (whatever they might be for the system in question) only carry data that actually gets used by the endpoint.
     
  15. Dec 29, 2007 #935 of 2401
    lrhorer

    lrhorer Active Member

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    I've heard a whisper or two about this from some of my colleagues who still work at TWC, but I really don't know any details. Of course, they would never divulge any confidential information, and I would never pass on any sensitive information to which I had any access, but from what I've heard, the "not ready for prime time" label is pretty accurate. Of course, IMO, the Scientific Atlanta 8300HD deserves the same label, in spades, and it's been out for a couple of years. For that matter, the entire SDV platform could qualify for the label in my opinion, the fact individual and specific deployments of SDV are working extremely well in many respects notwithstanding.
     
  16. Dec 29, 2007 #936 of 2401
    mikeyts

    mikeyts Stream Warrior

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    Before buying a TiVo S3, I used an Explorer 8000HD running Passport Echo for about 2.5 years and it was nearly as nice overall as the TiVo and I had no larger number of problem with it than I experience with the S3. There are several features of it that I miss dearly, though on the whole their absence is balanced by things that TiVo does better. I moved from a TWC neighborhood into a Cox one where they used the SA8300 running SARA, which is so wretched that I'm certain it would have actually caused me to suffer a fatal heart attack had I used it much longer. I was in a constant state of apoplectic rage while dealing with it. Had I stayed in the old place with Passport Echo, I'd have never been tempted to buy a TiVo.
     
  17. Dec 30, 2007 #937 of 2401
    pmiranda

    pmiranda New Member

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    If TW-Austin had ponied up the bucks for Passport software on their 8000HD, I might never have bought my S3. As it is, they're still SARA-only and I'd rather live without several SDV channels on my TiVo than live with their evil POS box.
    Hopefully the reports of the tuning resolver arriving late Q108 are real!
     
  18. Dec 31, 2007 #938 of 2401
    lrhorer

    lrhorer Active Member

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    I don't have any personal experience with the Passport software, but I have heard it is much better than the SARA software. It would be difficult for it to be worse. Nonetheless, I did enter into a feature comparison with a Passport user some months ago, and the 8300HD lacks a number of critical features:

    1. It can't be hacked, because the user doesn't own it.

    2. No TTB / TTCB.

    3. No TiVoWeb Plus or equivalent.

    4. No Galleon or equivalent.

    5. No Suggestions.

    6. The searches are not as flexible.

    I used it only as long as I had to, which was until the S3 was released. It was a constant and never-ending ordeal. Generally I was cursing fluently any time I used it - the term "used" being very loosely applied, indeed.
     
  19. Dec 31, 2007 #939 of 2401
    lrhorer

    lrhorer Active Member

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    You: :up:+2
    SARA: :thumbsdown:+100,000
     
  20. Dec 31, 2007 #940 of 2401
    lrhorer

    lrhorer Active Member

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    'Not here in San Antonio. All the new HD chanels are SDV. They add one every few days. Oh, and SDV works just fine with CableCards. It just doesn't work with unidirectional hosts like the TiVo.
     

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