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Cringley On Bandwidth-Expanding Modulation Technology

jtappan writes: "Robert X Cringely has an article describing a new modulation technology that will allegedly allow cable modems to run 10 times as fast, and which will eventually allow existing cable networks to carry 500 HDTV channels."

30 of 332 comments (clear)

  1. Hooray, 500 channels... by HardCase · · Score: 3, Funny
    And there's still nothing on...


    -h-

    1. Re:Hooray, 500 channels... by stu72 · · Score: 5, Funny

      True Story:

      I grew up in a remote northern mining town in the Yukon (that's Canada, if you didn't know) We only got 1 channel for a number of years, and that was CBC, the national public channel. So I grew up on the standard kids fare they carried, Sesame Street et al.

      Thing is, there was a dirty little secret I didn't learn about until quite recently. I may have thought I was learning my abc's with the rest of the country, but in fact, I was a day late.

      There was no CBC reception in that area. Every day, 24 hrs of the previous day's broadcast was taped and flown up, to be rebroadcast 24 hrs late, on a small transmitter in town.

      So even back then, we had decent bandwidth capacity (coulda put more tapes of other channels on the plane), just horrible latency. :)

    2. Re:Hooray, 500 channels... by JabberWokky · · Score: 3, Funny
      So even back then, we had decent bandwidth capacity (coulda put more tapes of other channels on the plane), just horrible latency. :)

      Yes, but you only had one transmitter, so you faced that peskey last mile issue even then. ;-P

      --
      Evan "Wasn't Oz the usenet feed that went on tapes by mail?" E.

      --
      "$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
  2. My favorite quote... by brunes69 · · Score: 4, Funny

    I have boxes filled with old modems, ISDN routers, and Ethernet hubs that are all perfectly functional, but useless to me. I have closets filled with old computers that run like a charm...

    After reading this, I sent Cringly my shipping address. Do you think this is a bit too forward?

  3. Not with Cable companies at the head. by wickidpisa · · Score: 5, Interesting

    I almost got excited about this, then I realized that the Cable companies couldn't manage a decent ISP if you held a gun to their heads (believe me, I wish I could). As someone who has had cable modems since '95, let me tell you it has not been pretty. After the recent @home fiasco, I have lost all faith that even if this technology ever comes about, that it will be even close to anyone's expectations because the cable companies will ruin it.

    1. Re:Not with Cable companies at the head. by Erbo · · Score: 3, Interesting
      Exactly. Scott Adams pointed it out best: "Cable companies are staffed with people who couldn't get jobs at telephone companies." (The Dilbert Future, p. 45) He pointed this out in the midst of a discussion about ISDN, which the telephone companies managed to muck up, despite the fact that they already know how to provide two-way communications. (The book was written in 1997, so DSL wasn't mentioned.) The cable companies are starting from further back in the "stupidity" race.

      Not to mention that cable companies tend to be an anal-retentive bunch in the first place, and are bound to slap lots of restrictions on the way you can use that fat pipe. (Comcast, anyone?)

      Eric

      --
      Be who you are...and be it in style!
    2. Re:Not with Cable companies at the head. by patchmaster · · Score: 3, Insightful

      I've been with six different ISPs during my time on the Internet, including a major phone company, two small, local ISPs, and two giant, international ISPs. Of all these, my Time Warner/Road Runner service has been far and away the best, both in terms of reliability and of service provided (email, newsgroups, etc). And that's not even considering the speed. I know a lot of cable companies have done a very poor job at providing Internet service, but they aren't all total dunces. Time Warner took their time with it, but from what I've seen over the last couple years they've done it right.

  4. Wavelets wash back by maggard · · Score: 4, Insightful
    Great - wavelets are back again; however this time not for compression but for high-speed signaling and to avoid interference.

    Cringely reports the folks are about to set their design in silicon so we'll find out then but I'm not holding out a lot of hope. On the other hand the basic theory is pretty easy to test and apparently they've convinced more then a few folks who've apparently done their due diligence.

    • If the signal propagates properly
    • If it can be discerned from ambient noise and other channel's interference
    • If the processing delay isn't too great
    • If the chipset is cheap enough
    • If the upstream folks roll it out
    Etc.

    ps To every first year student - think carefully before pointing out why this won't work. I expect that better minds then yours have had a look already so check your numbers and facts before posting please.

    --
    I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
    1. Re:Wavelets wash back by Zeinfeld · · Score: 5, Insightful
      Great - wavelets are back again; however this time not for compression but for high-speed signaling and to avoid interference.

      Reading the article I think that Cringely's biggest problem is that he does not understand how long it takes to get technology from a proof of concept to a working system.

      With the Web it has taken ten years and counting to get this far. Idiot pumpers like Meaker and Blodget aside, Internet time runs at 1 for one with GMT at best.

      I first heard about ISDN in the 80's, ten years later people started to get ISDN phone lines. Likewise with DSL the basic ideas were floating arround in the early 90s but are still not fully baked for deployment.

      It does not seem unreasonable that people will be rolling out much faster cable networks in (say) 2010 or so. I don't think it is going to happen on any larg scale before then however. The DOCSIS standard has only just been developed and it will take at least 3 years for any radical redesign to make it into a spec and another 2 to get into production, then there will be the inevitable delay as results from trial deployments are assesed and so on.

      What cringely and co miss is that athough the majority of the cost of a fully deployed system is at the consumer end s not where the killer costs lie. To roll out broadband access in a town you first have to buy lots of gear that typically comes with five or six figure price tags. You have to buy that gear whether one person buys service or ten thousand. The client end costs are not so much of a problem because each customer pays a subscription.

      That is why the cable companies partnered with the losers @Home to deploy broadband. The cable cos were not prepared to gamble their capital on the success of broadband. @home was. Of course the minute that there was proof of the business plan @home became surplus to requirements

      So yeah, wavelets, whatever, but at the moment the bandwidth in the last mile is not the bottleneck. Nor is the bottleneck in any of the pipes. There were four companies that deployed fibre backbones over the last five years, each of which has more capacity than the country could use before 2015. It is the switching capacity that is expensive and that comes down to pricey silicon and probably always will. If you have computing technology of power X you end up with switching nodes that require processing power of many, many X.

      --
      Looking for an Information Security student project suggestion?
      Try http://dotcrimeManifesto.com/
  5. I don�t see how this helps anything by G00F · · Score: 5, Insightful

    Camblemodems are able to run much faster than they currently do. They are told to run so slow for a few reasons.

    1. Cost them money to get the big pipe for the users
    2. Make you play well with others
    3. They tailor the service for people who would not be willing to pay more for more bandwith.
    4. They have a monopoly, so they can do what ever they want with very low risk of losing you to compitition.

    I've downloaded 700k a second, and uploaded over 500k a second on the old lancity cablemodems in fremont cali years ago. Sicne then they have pushed cablemodems that they can control the speeds on. And they do, they slow them down hugely.

    --
    The spirit of resistance to government is so valuable on certain occasions that I wish it to be always kept alive
  6. What's The Point (for cable modems)? by John_Booty · · Score: 5, Insightful

    It's nice that ISP's could provide 100x faster service, but they're already capping the bandwidth they DO provide. I think this technology is solving a problem that simply doesn't exist in the cable ISP game.

    That's not to say this tech doesn't have other, awesome applications. But I don't think cable companies are exactly going to be lining up to roll this out. :-)

    --

    OtakuBooty.com: Smart, funny, sexy nerds.
  7. Hey Taco by SubtleNuance · · Score: 5, Insightful

    Why dont you can Katz and give Cringley a job?

    I wonder what the ratio of katz-ignoring-slashdotters vs cringley-article-hits is.

    1. Re:Hey Taco by Anne_Nonymous · · Score: 5, Funny

      Screw Robert X Cringely; I wanna see a column by Malcolm X Cringely! Something like:

      "The economic philosophy of modulation technology only means that our people need to be re-educated into the importance of controlling the economy of the cable modem with which we browse, which means that we won't have to constantly be involved in picketing and boycotting other ISPs in other communities in order to get bandwidth."

  8. Sounds like what happened with modems by redelm · · Score: 5, Informative
    Well, at least they're not claiming they can beat Shannon's limit. 10 Gbit/s doesn't sound too unreasonable for coax. If you can't drive the frequency higher than say 500 MHz, you could still encode a constellation of 20 bits per transition.


    This is similar to what modems do. AFAIK, they still don't run any faster than 3750 baud (Hz),
    but they can encode up to 15 bits per wave to get 56kbit/sec. If the line isn't so quiet, they cannot distinguish all 15 bits, so the modems have to negotiate a constellation with fewer bits.


    My question is how this will work with an ethernet-like collison detection system that AFAIK cable modems use. The jam signals could get ugly, and I'm not sure you can carry as my info on broadband as baseband systems. Or how cable decoders will cope.

  9. They won't improve cable modems. by Xife · · Score: 3, Insightful

    Cable modems will keep the same data rate, they'll just decrease the bandwidth by 10X and put a bunch of HDTV channels in the remaining bandwidth.

    Of course it will be years before that happens because users that own their cable modems and will be resistant to buying a new one for the same data rate, and the cable company will have to replace the modems for people who rent. This will reset the break even point for the extra $10/month you pay for renting the modem, which doesn't sit well in a business plan.

    --
    ---- Smokin' another sig.
  10. What a fucking shill by SumDeusExMachina · · Score: 4, Troll
    This "article" by Cringley looks like marketing copy from this Rainmaker Technologies company. Just to quote some particularly glaring examples:

    Rainmaker's is a compelling argument for cable operators who can see their infrastructure lasting years longer than they ever hoped. Suddenly, the fight over whether and how to carry HDTV is over at the same time that wavelet modulation enables new services at both the top and bottom of the digital food chain. Ten gigabits-per-second would make possible practical videoconferencing with high quality video at the same time that wavelet modulation's lower power requirements would support lifeline voice-over-IP telephone service even after the power goes out.

    Really, does this guy have any shame? And what's all this about astroturfing for M$'s .NET initiative? It really isn't all that great, dude. You're just a marketing dupe.

    --

    Is your company running tools written by ma
  11. Anyone remember Transmeta? by timholman · · Score: 5, Insightful

    After reading the article, I checked out Rainmaker's site. These guys have a theory, some patents, and some simulations. What they don't seem to have is any working hardware that proves this 10X bandwidth increase can actually be achieved in residential cable systems.

    Does this remind anyone of Transmeta, who promised processors with a fraction of the power consumption at higher speeds? Everybody loved them when all they had was a press release. The actual product didn't work as advertised, and now they've faded away.

    If it sounds too good to be true, it probably is. 10X uber-bandwidth schemes sound suspiciously like 10X uber-compression schemes. I'll reserve my enthusiasm when I see working hardware.

  12. Blatent Karma Whoring Link by slashdot.org · · Score: 4, Funny

    Rainmaker's website who make the tech he's talking about. (Like no one would have found this link otherwise)

    You got to wonder if this is one of the SEC sites.

  13. Cringley's weak spot by baka_boy · · Score: 3, Insightful

    I'm not even going to try to evaluate the technology Cringely keeps rolling out week after week: IANAP (I Am Not A Physicist), and between the UWB debate last week, and now wavelets for networking, I'm throwing in the towel.

    However, he keeps talking about how all these new technologies are going to roll out any day now, with no increase in cost. That's simply wrong. From the cable (or telco, ISP, etc.) point of view, they have basically no reason to drop the prices on their current services more than a pittance -- people are still queueing up on six-month waiting lists for good ol' 256Kbit DSL, so why should they turn around and offer 1-10Gbit for the same price?

    You could argue that competition will drive prices down, but that would be naive as well. The telecommunications market isn't open: it's a cabal, just like the recording industry, and other favorite /. demons. Collusion between the few big players will keep any new technology carefully overpriced until the last possible drop of profit has been squeezed out of the old.

  14. I don't mean to sound snide but... by JoeShmoe · · Score: 5, Insightful

    ...if Slashdot is going to be posting nearly every single article that Cringley writes (five times this past month) shouldn't he basically get his own Slashbox or topic?

    I mean, I know Slashdot is a user-submission site but of given Cringley's anti-Microsoft pro-techi slate I think it's a given that someone's going to be submitting everything he writes. Shouldn't Slashdot be somewhat discerning in which articles they post? If I wanted to read everything he wrote I would just bookmark his site (as I have done). To see it posted on Slashdot every week seems, I'm sorry, -1 Redundant.

    How about we just link this and be done with it?

    http://www.pbs.org/cringely/pulpit/

    - JoeShmoe

    .

    --
    -- I wonder which will go down in history as the bigger failure: the War on Drugs or the War on Filesharing
  15. Cringley and the OSI model by aderusha · · Score: 5, Informative

    while i enjoy cringley columns, his mangling of the bottom layers of the OSI model made me cringe (pun intended).

    encoding systems are physical (layer 1) technologies, not 2nd layer like he claims. he further states that ethernet and token ring are layer 3 technologies, which is blatently false - they are both data link technologies.

    maybe i'm just being nitpicky....

  16. Modems are maxed out by BeBoxer · · Score: 5, Insightful

    Modems are basically completely maxed out given the contstraints that they operate under. Your math assumes getting 10 bits per hertz (realistic) and getting 56KHz (unrealistic). The phone system is designed to carry voices, not binary data. As a result, it's optimized for the frequency range of the human voice, which only extends up to the 3-4KHz range. In fact, unless you live in the sticks and are calling your neighbor, it is almost for certain that your call is being carried digitally. If so, it's being sampled at 8Hz meaning that due to Nyquist you can't send any frequency higher than 4KHz thru the phone system. Period. You'll notice that if you figure out the bits/hertz that a 56K modem sends, its as good (~8 bits upstream) or better (~13 bits downstream) than what this company is claiming to get.

    Basically, they have a system which works as well as a phone modem. Not too suprising really, I suspect that the fundamental limitations on signal and noise are pretty similar for the two different kinds of copper wire run to your house.

  17. Cablemodems can already be much faster than we get by technopinion · · Score: 4, Informative

    I'd rather see advances in backbone speed than last mile speed, thank you. Cable modems are already capped at a fraction of their potential because of insufficient capacity at the ISP side. Give the ISP a couple of gigabit connections, open up the cablemodems to 10mbits, and I'll be perfectly happy, for a couple of months anyway...

  18. Re:Boost or stomp cable providers? by GreyPoopon · · Score: 3, Insightful
    Or, is this what cable providers are looking for, a high bandwith solution cable of sending multiple HTDV channels as well as very high-speed broadband.

    I would say that this is exactly what they are looking for. It gives them:

    1. Much more bandwidth for an existing cable modem connections. This provides leverage against the argument that DSL always tries to use against the "shared connection" issue.
    2. Less need to build out as much in new areas to meet anticipated capacity requirements.
    3. The ability to send many many more channels down the same line, making customers feel happier even though there still won't be anything worth watching.
    4. The ability to meet Federal proposals on pushing HDTV without angering older customers who want to wait for their TV to die before they switch.
    --

    GreyPoopon
    --
    Why is it I can write insightful comments but can't come up with a clever signature?

  19. Re:Can anyone explain wavelets? by the+eric+conspiracy · · Score: 5, Informative

    Wavelets are an alternative to Fourier Transformation of time domain data to obtain a functional decomposition of the waveform for analyis or processing. They are particularly useful with choppy or spikey signals.

    It's a very fundamental mathematical tool for any kind of signal processing application. As such it has a wide range of applications. It came into wide use perhaps 15 years ago; perhaps you were out of school by then. I am sure that every EE undergraduate is getting exposure to wavelets these days.

    Here is a link to resources on Wavelets:

    http://www.mathsoft.com/wavelets.html

  20. Re:Great! by Mr+Z · · Score: 5, Insightful

    Actually, Cringley gets it wrong. Modulation happens at the PHY layer, not the LINK layer. So either this is a crock of s**t as big as what ZeoSync was stirring, or Cringley has his head up his arse. Notice that that's not an exclusive-or.... both could be true.

    This link pretty much covers it. I'll quote the most relevant bits:

    1. The Physical Layer describes the physical properties of the various communications media, as well as the electrical properties and interpretation of the exchanged signals. Ex: this layer defines the size of Ethernet coaxial cable, the type of BNC connector used, and the termination method.
    2. The Data Link Layer describes the logical organization of data bits transmitted on a particular medium. Ex: this layer defines the framing, addressing and checksumming of Ethernet packets.

    So, in other words, the Physical layer is where signaling happens. (This is where QAM and this wavelet snakeoil are relevant.) The Link layer is where PPP, SLIP, and Ethernet Packet encapsulation happen. (Not Ethernet signaling, just the 802.3-or-whatever framing spec.)

    --Joe
  21. Re:Great! by isdnip · · Score: 5, Informative

    Mr. Z is correct -- moderators, promote the note I'm replying to! Cringely is wrong about layers. Layer 1 does all the bit stuff, including modulation and even ATM cells. (Layer 2 is about user-sized frames and error detection.)

    But that's not what matters. Shannon matters. You can't defeat Shannon, and Cringely admits it. So let's see... Shannon basically says that the limit of bps is proportionate to the product of bandwidth times the log2 of the signal to noise ratio. So if you have an infinite SNR, you can have infinite bandwidth. But getting 33 Mbps (around the top end of DOCSIS cable modems) requires good SNR. My cable modem right now has 36 dB SNR and is running QAM64; DOCSIS adapts speed to line quality.

    So even if wavelets were better than QAM (and I can't say, because Cringely doesn't tell enough to know if this is real or a scam), there's just not that much more you can do in 36 dB! (Shannon limit of 6 MHz at 36 dB is around 6M*12=72 Mbps.)

  22. Re:1024QAM by $pacemold · · Score: 3, Informative
    Yep, that's right! From the Rainmaker Technologies website:

    Our application in cable modulates an 18MHz baseband multi-sub-band signal.
    ...
    The downstream data capacity of the channel will be 170Mbps, running with an effective baud rate of 10 bits per second per Hz, equivalent to 1024QAM.

    1024QAM does give you 25% improvement over 256QAM - after all, it packs 10 bits in space where 8 bits are now. The wavelet may do some additional magic with sidebands, but if you use plain old 256QAM on 18 MHZ channel, you will get about 120 Mbit/s. 40% improvement is good, but is it good enough to convince cable companies to change standards?
  23. Just give me a pipe by uberdave · · Score: 3, Insightful
    Just give me a pipe big enough for one or two HDTV channels, a couple of two way audio channels, and a 100-1000Megabit/sec TCP/IP.

    The way I see it, cable companies are doing things wrong. Instead of bundling an internet channel within their video channels, they should be sending video on demand channels over an internet pipe. One cable, or fibre into the home, into a box that splits out a number of phone lines, a number of video channels, and a number of ethernet lines.

    The problem is that the infrastructure is not there. Of course this scheme would cause telco vs cable wars, ISP vs. telco wars, etc. Our bright shiny future gets pushed back a few more years.

  24. Cable is wrong topology by Martin+S. · · Score: 3, Insightful

    Cable Systems have the wrong network topology to become the long term solution to the requirements of a broadband society.

    They are rings and as such will always suffer from the contention being too close to the customer, leeches will always have a very negative impact.

    Star based solutions such as xDSL offer much between solution. The bandwidth becomes more dedicated and contention is moved up stream, where the capacity can be managed in a much more effective way. Over time the 'last mile' is reduced so the xDSL become a bigger pipe, until ultimatly we have a star made from fibre rather than a fibre ring. Everbody wins, consumer, supplier, society.