Brian Roberts created quite a stir at The Cable Show earlier this week when he showed off the new super modem that could bring data to your homes at about 160 megabits per second. The demo was great (watch video) but it was a lot of […]

Brian Roberts created quite a stir at The Cable Show earlier this week when he showed off the new super modem that could bring data to your homes at about 160 megabits per second. The demo was great (watch video) but it was a lot of FUD, Here are five reasons why:

* The modem is based on DOCSIS 3.0, which allows the cable operators to offer 160 megabits down and 120 megabits up. At some point in the future it will be expanded to a shared gigabit, thanks to Cisco.
* These speeds are shared, not dedicated. In other words, you, the subscriber is going to get between 20-to-50 megabits, NOT 160 megabits per second as Roberts said. Comcast has about 400 customers per node, and imagine all of them logging on at the same time.
* It is not going to be in couple of years. In 2005, gear maker ARRIS was talking about availability in two years. ABI Research had predicted shipments in 2007 and 60% market penetration by 2011. Looks like we are running late on those forecasts, so why should it be any different this time around.
* Even though TI is talking about shipping DOCSIS 3.0 related silicon in early 2008, sources say that might be too optimistic. There is a lot of hedging going on in the ecosystem, especially on the chip-side. 2010 is my best estimate on when this new superfast modem does show up.
* Historical Fact: Roberts’ future spin is good, but let’s not forget Comcast was an investor in @Home, which offered 10 megabits down service back in the day. Before cable companies killed it, of course to sell their own slower services.

So why did Roberts show off the modem? My best guess: Comcast and rest of the cable industry is actually quite scared of Verizon’s fiber approach. What do you think?

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  1. Jeffrey McManus Friday, May 11, 2007

    I think your analysis nails it, Om. I have no idea if we’ll ever get FIOS in my nabe in San Francisco, but the second it arrives, I’m dumping our DSL. If the TV package Verizon offers is a better value than DirecTV, I’ll happily dump that too.

    I’ll never give a dime to Comcast but I’m sure there are tons of Comcast subscribers who will be thinking like me when they have a FIOS/TV alternative.

  2. Hey Om -

    Couple of comments to your post.

    First point/Downstream rates – 160 Mbps is the minimum specified (4 x 6 MHz channels). A shared gig is possible (if demand was there) now and Cisco is one of several CMTS vendors that could support this.

    Second point/Consumer speeds – Again, 4 channels is the minimum per bonding group. There are no technolgy hurdles to deploying more than one bonding group per node. If consumer demand supports this the technology supports this.

    Fourth point/Availability – modems will begin shipping in Q1 2008. In some cases, they may be pre-deployed (which means that the CMTS is scheduled for upgrade).


  3. Peter,

    I did mention the 1 gig shared upgrade path. The issue is when.

    on the more channels being available, it is going to be tough since they need all the bandwidth they can get for HD. I pointed that out in my previous post.

    The DBS guys are pressing their advantage. Echostar released their numbers earlier this week. that says it all.

  4. The intuition says that just comparing the access speeds between multiple access cable modem access and FiOS gives any indication on the user experience. Doesn’t it depend on the concentration placed by either system upstream? Isn’t it possible that even though Comcast puts less concentration upstream and FiOS has higher concentration so much so that the user experience is a flip of what you are suggesting? Given that Internet is a statistical multiplexing system, I would prefer to see a metric that reflects that statistical nature rather than a fixed deterministic value.

    Also I do not see the benefit of ever increasing access speed without a corresponding increase in the core. Currently users see the difference because the access speeds are low compared to the core speeds. But eventually I suspect that it will not matter.

  5. Hi -

    Your point on total capacity is the real issue. I think that D3 is only one of two necessary technologies needed to achieve “spectral happiness”. The other being SDV … and this is now a bit clouded thanks in large part to Rep. Anna Eshoo’s misguided concerns/comments at yesterdays hearing on the hill.

    By the way, I am a huge DISH fan …


  6. The reason for the pre-announcement might be Comcast’s recognition that it is going to end up in the bandwidth and not the content business. Hopeful sign is the quote from Roberts: “What consumers actually do with all this speed is up to the imagination of the entrepreneurs of tomorrow.”

    I agree with your skepticism on the actually obtainable speeds on the shared backbone.

    Posted more on all this http://blog.tomevslin.com/2007/05/wideband_via_ca.html

  7. I think the Omster has it on this one.

    I think ‘big cable’ has a big problem on their hands with FiOS on two fronts.

    1. the technology is more well thought out in my opinion.

    2. It already has SIGNIFICANT market ‘mind share penetration’ with the main stream user. Most casual users are aware of FiOS and think of it as the market leader in terms of performance bar none.

    I think cable figures they have to do something from a marketing perspective before its too late.

  8. I believe that the main audience here was Wall Street. Comcast needs to show that it can provide a service similar to Verizon’s without a major plant upgrade. Cable spectrum limitations are real, and much of the activity in The Cable Show was concentrated around BW saving technologies. Spectrum availability will be the main limitation to the speedy adoption of DOCSIS 3.0.

    In the Silicon Valley area, cable modem speeds are 8~12Mbps throughout the day. This comes on a single 38.8Mbps channel that is shared between ~750 homes (oversubscription statistics simply work). Scaling this oversubscription to 100Mbps requires ~50MHz of spectrum. However, since the BW heavy applications don’t yet exist, and not everyone will sign up to a more expensive service, I bet that it could be done with a 24MHz addition. But were can you find 24MHz in a crowded to the rim 750MHz plant?

    It is very likely that the first MSO to deploy this technology on a large scale will be COX, and sooner than you may think. Up until 2.5 years ago, Cox was constantly telling Wall Street how a 750MHz plant will suffice forever. Then Cox went private, and now it’s in the midst of a capital intensive 1GHz plant upgrade. 250MHz of new spectrum provide 1.6Gbps for every node, and a little of this can be allocated for DOCSIS 3.0. My guess is that the first to enjoy the new cable modem speeds will be the lucky residents in Cox’s flagship plant in San Diego. Alternatively, Cox can start with an area which overlaps Verizon’s FIOS deployment.

  9. Brian Roberts is an idiot. I remember being at a show 2 years ago and he said “I didn’t know what IP stood for so I called up Bill Gates to ask him.” Gates must’ve been chuckling after that call.

    Here’s the deal Brian: You can channel bond all you want but you only have 850 MHz to play with. You want to give people 150 Mb/s – well you better forget about delivering any linear channels or any VoD because your entire network will be devoted to broadband.

  10. The speeds are shared between multiple homes. However, that’s not a change from the current cable modem standard. The difference in DOCSIS 3.0 is that you’re sharing at least 4 channels, instead of a single channel in DOCSIS 2.0.

    I do think that cable operators will be able to implement DOCSIS 3.0 at the beginning of next year. That’s when the equipment is set to be certified.

    I’ve already heard of a Singapore cable company that’s implemented Pre-DOCSIS 3.0 (for 100 Mbps service). And I believe Pre-DOCSIS 3.0 is pretty much the same thing as DOCSIS 3.0 (I have a feeling the only difference between Pre-DOCSIS 3.0 and DOCSIS 3.0 is that the equipment just hasn’t been certified as DOCSIS 3.0 equipment).

    Now, whether any US cable company chooses to implement DOCSIS 3.0 at the beginning of next year, that’s another story.

    Actually, I don’t think they need to find 4 channels to do DOCSIS 3.0. They’re already using one channel to do DOCSIS 2.0, so to do DOCSIS 3.0, I think they need to find 3 channels.

    Typically, cable systems today have something like 120-130 channels available for use. Given all the crap that’s on TV these days, I bet I could easily find 3 channels that deserve getting the ax. That being said, I am not familiar with the agreements that cable companies make with content providers, so I’m not sure how easy it is to actually terminate a channel.

    And about Verizon. You have to remember that Verizon is only rolling out FIOS over their existing plant. Most of the US is served by AT&T, who is doing their U-Verse thing (which is a joke). And there’s also Qwest, who doesn’t seem to have a plan at this point.

    Given all that, I’m willing to bet that the only areas to get DOCSIS 3.0 in the near future, are the areas where FIOS is available.

    Also, you have to remember that HD is a problem for everybody. I’m not sure that Verizon, at least with its BPON architecture (which provides 622 Mbps per wavelength), is in any better of a position as far as HD goes. And, of course, AT&T and Qwest are basically nowhere on HD.

    But to answer your question on where cable will find the channels for DOCSIS 3.0, I have a feeling they’re going to try to implement SDV (switched digital video). I think Cablevision has already done some of this. Supposedly, you can get about a 40% reduction in bandwidth usage.

    FYI: other options for for getting the channels for DOCSIS 3.0 are: moving from MPEG-2 to MPEG-4, moving to an all digital television broadcast system, and upgrading the plant from 860 MHz amps to 1 Gig amps.

    And one last thing, its not like you can get 160 Mbps from anybody right now (I’m pretty sure Verizon doesn’t come close to this either). And why would you want to? Remember that even if you can receive 160 Mbps, unless the computer you are communicating with can transmit at 160 Mbps, you’re not doing to receive at 160 Mbps. So, basically, right now, I don’t think a 160 Mbps service is worth a whole lot for most people.

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