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Cringley On Bandwidth-Expanding Modulation Technology 339

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."
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Cringley On Bandwidth-Expanding Modulation Technology

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  • by HardCase ( 14757 ) on Thursday January 31, 2002 @06:59PM (#2934226)
    And there's still nothing on...


    • by uberdave ( 526529 )
      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.

  • by brunes69 ( 86786 ) <`gro.daetsriek' `ta' `todhsals'> on Thursday January 31, 2002 @07:03PM (#2934255) Homepage

    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?

  • Doesn't Matter (Score:2, Redundant)

    by Anonymous Coward

    Cable modems are already capped. This just
    means 10 times more unused potential. There's
    no competition forcing providers to open up
    those pipes.
  • by wickidpisa ( 41827 ) on Thursday January 31, 2002 @07:03PM (#2934263) Homepage
    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.
    • 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?)


      • 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.
    • In Reston, Va, and I haven't had any trouble yet. Two or three outages in the past year, neither of which lasted long, and good tech support.
      • Reston, Va, and I haven't had any trouble yet. Two or three outages in the past year, neither of which lasted long, and good tech support.

        Try running a web server....

  • As long as the cable companies as still connected to the same T1s and the same number of home users have the machines on connected to bearshare.

    Making the cable modem faster may be nice sometimes i suppose. BUT this does not mean that max throughput of the Cable company will expand. All it means is that it will be EASIER for LESS users to saturate a Cable companies bandwidth. They would be stupid to upgrade their existing clients or future users to a technology that will cost them more money in transmission costs. They already gripe about usage the way it is. Do you really think they will willing make it easier to suck up more bandwidth?

  • It seems that the last few articles cringley has wrote have been about technology that is facinating and very exciting. So when am I going to get my fuelcell powered car with my uwb radio, that takes me with my laptop with a solid-state harddrive to my personal airplane?
  • Wavelets wash back (Score:4, Insightful)

    by maggard ( 5579 ) <> on Thursday January 31, 2002 @07:08PM (#2934297) Homepage Journal
    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

    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.

    • by Zeinfeld ( 263942 ) on Thursday January 31, 2002 @08:45PM (#2934818) Homepage
      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.

      • 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.
        The standard that is currently deployed is DOCSIS 1.0, with DOCSIS 1.1 equipment available and used in new deployments. Cable companies have no desire to upgrade to 1.0 to 1.1: the equipment, expensive CMTSes and numerous CMs, is still new.

        Meanwhile, CableLabs just rolled out DOCSIS 2.0 with new upstream PHY (two different modulations that MUST be implemented, because CableLabs couldn't deside which one to use!), so the roadmap is pretty much known for the next 10 years.
      • 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.

        People talking about Internet Time are usually talking about the fast-release cycles of software via the internet. The classic case was Netscape back in the early days.

        I don't know anybody that refers to Internet Time when talking about hardware or new technology...
        • People talking about Internet Time are usually talking about the fast-release cycles of software via the internet. The classic case was Netscape back in the early days.

          Ahh so what was called Internet time was no more than the phenomena of companies releasing what used to be called Alpha release software to the public?

  • Sure, it would be a great technological advance. Unfortunately, as we have all seen, this really means very little. Espically in the ISP game. With the recent consolidation of ISPs into 3 or 4 major players, getting this type of thing out seems even more difficult. We can't even use the technology we have. Cable companies limiting bandwidth. DSL providers requiring you to log off every 2 hours. None of that is necessary to the technology, but those in charge feel the need to add these "features" in order to squeeze every last bit of cash out of the users. Not to mention trying to get them to roll something new out. Good Luck.

    When I look at where we are headed, sometimes I just get more and more depressed.

  • by G00F ( 241765 ) on Thursday January 31, 2002 @07:11PM (#2934323) Homepage
    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.
    • It doesn't help you and me. It helps the cable company. This way they can have more bandwidth on the pipe, therefore where they used to have to have your neighboorhood and another on seperate hookups, now they have the bandwidth for half the county to get on at the same speed.
  • by John_Booty ( 149925 ) <johnbooty@bootyproject. o r g> on Thursday January 31, 2002 @07:12PM (#2934330) Homepage
    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. :-)
    • Unfortunately true.

      Here in New Zealand the main form of fast 'net access is ADSL. There are other systems, like the recently-featured CityLink [], a 10M-1G (depending how much you pay for your link) city-wide ethernet, but unless you live in Wellington (or want to hack your routing and lose your connection every time it rains with a satellite connection []), ADSL is pretty much the only way to get your fast 'net access.

      The only problem is that the ISPs on the network seem to be chronically short of bandwidth. Xtra [], the ISP associated with the local telecommunications monopoly [], regularly has people complaining about it when they only get 4kB/sec out of their 128K DSL links.

      (This is for 'JetStart', the 128K rate-limited DSL which comes for US$30/month. Even that is saturated! You can get 8 Mbit downstream with JetStream [], at a horrible cost, e.g. US$250/month for 3 gigabytes of traffic).

      What would be very cool would be if a provider took this up and used it for local point-to-point connections, say if I wanted to connect my LAN with my friend's one, over on the other side of town. Or a business link - a 10X speed boost would be much appreciated!
    • From a white paper on wavelet technology from Rainmaker's site:

      Wavelet modulation provides reliable high-bandwidth transmission of data, voice and video over existing wireline (phoneline and powerline) and wireless media.

      It doesn't seem clear why this is a particularly cable-oriented technology. The fact that they say it can be used for wireless would seem to hurt cable more than help it. I understand that the cable guys are going to be able to extend the life of their wired infrastructure, and maybe make money off of 3rd party providers, but if wavelets can be used to jack up the b/w in wireless, then I think this is pretty bad news for any wire providers.

      As far as I can figure, getting fat (or reasonably fat... 1Gb/s) b/w on a cellular link (or CDPD, or sat-tel, or whatever) would attract people who want applications like voice/IP, e-mail, messaging, chat, Web browsing, etc. on a mobile platform. Wire will be fine for big stuff like HDTV, server traffic, etc., but I bet most consumers don't use most of their b/w most of the time. (They would just like to know that they COULD take advantage of a fat pipe when they need it... maybe someone should come up with a "bandwidth/QOS on demand" scheme?)

      I don't think Cringely is that great a reporter, and the fact that he focuses completely on cable makes me wonder. And judging by the uncritical "Ra! Ra! Rainmaker!", I'd say that he doesn't plan on remaining a non-investor for long.

    • Yes, but the question is why do they cap bandwith right now?

      The reason is that the cable providers are already facing a problem of saturation of their networks, because they have over-sold access. If this technology is on the level, it will allow them significantly reduce their loads during peak times, increase the number of subscribers, and possibly even lower their prices.

      Believe me, cable companies will be salivating over this.
    • 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.

      The same issue may apply with the 500 channels of HDTV. How many cable systems actually use that number of channels, even with inbuilt time shifting...
  • Hey Taco (Score:5, Insightful)

    by SubtleNuance ( 184325 ) on Thursday January 31, 2002 @07:12PM (#2934335) Journal
    Why dont you can Katz and give Cringley a job?

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

    • Better yet, pay Cringley to write followups on Katz. That would be quite, ah, entertaining. ;-)
    • Re:Hey Taco (Score:5, Funny)

      by Anne_Nonymous ( 313852 ) on Thursday January 31, 2002 @07:49PM (#2934557) Homepage Journal
      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."
    • I'll second that.

      I've had Katz on ignore for almost a year now.

      Still I don't think Cringely needs to stoop to /. to get published.
    • But the should still get a Cringley icon. I recently suggested photos having to do with Dave Letterman and got modded down for it. Because of that evil moderation I won't reproduce the links of the photos, but those willing to do the research will find that they are strangely similar. Dave and "Robert" that is. We don't know his real name do we? Could it be ...... Letterman???? Perhaps twins separated at birth?
  • by redelm ( 54142 ) on Thursday January 31, 2002 @07:13PM (#2934337) Homepage
    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.

    • Actually, if what he is saying is true, then your modem could go to 560kbit/sec by replacing QAM with Wavelet encoding. From the sound of it, it would also be able to establish the full 560kbit over a greater range due to better noise resistance.

      Of course I don't know if this is an all or nothing proposition (560kbit/s or no connection at all) In which case it would really suck.

      It also sucks that they are targeting cable modems, not phone modems.
      • by BeBoxer ( 14448 ) on Thursday January 31, 2002 @07:54PM (#2934583)
        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.
    • A 33.6kbps modem runs about 3 kilobaud, with an 11 bit per symbol QAM constellation.

      A 56kbps modem runs 8 kilobaud, with 8 bits per symbol. The telco digitizes voice at 8 bits per sample, 8 ksamples/sec, and the modem actually is just using that. However, the phone company "bit-robs" the signal, taking a few bits here and there to do in-band signaling on the line, hence why the modem cannot rely upon getting all the bits, all the time.
    • They'll run into DSL's biggest enemy: reflections.

      Reflections need an echo canceler, and at high sample rate that means a lot of taps per milisecond echo delay, and all those tapes for each incoming sample, so a big & hot chip.

      If reflections weren't a problem, DSL would have been a lot more problem-free and faster too.
      • They'll run into DSL's biggest enemy: reflections.

        That's true for Cable TV, so Cable TV cables are already relatively clean.

        This is probably one of the reasons they are focusing on cable TV. Most other existing wired technologies (phone, ethernet, speaker wires, etc...) tolerate reflections much better, so the infrastructure has a lot more of them.

    • Downlink (Score:2, Interesting)

      by dachshund ( 300733 )
      My question is how this will work with an ethernet-like collison detection system that AFAIK cable modems use.

      Current cable modems have separate downlink and uplink signals, running on different frequencies. Only the uplink signal has any need for collision detection; the downlink signal all comes from one source (router or switch), so there's no need to worry about collisions.

      I can't claim I have a good idea of what they're trying to do here. But if they're proposing a system that can run over a broadband line, with a separate downlink and uplink, then they would simply apply the new modulations to the downlink. You might also find some way to apply the technique to the uplink, but it's nowhere near as important.

      If they're proposing something closer to Ethernet, then they'll need to rebuild the system from scratch. I have no idea what they'll do to avoid collision problems.

  • by Xife ( 304688 ) on Thursday January 31, 2002 @07:17PM (#2934373) Homepage
    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.
    • Yeah, you're telling me.

      You got them pegged.

      I live in one of the pilot cable modem towns... Like the 4th nationwide to get cable modem service. I first used cable Internet around 1995, our high school got one.

      They still have the ancient Zenith modems in service, and just a couple months ago started to move to DOCSIS.

      The old modems had no rate limiting capabilities, so anyone could saturate the T1 they had to the Internet (it's a small town with not many geeks, so they can get by with a single tier 1 T1 and some peering T1s to their other locations nearby).

      Anyway, they talked about migration to DOCSIS for the last 3 years, and they are just getting around to it. Cable modem companies are really resistant to changing the customer hardware.

      One good think about those old Zenith modems though, was they were like an ethernet hub, you could see the activity and collisions on the cable side. That also gave away their secret that the collision light stayed on without flickering at all from 10:30 am until 8pm.

      Somehow you could still pull down around 30KB/sec every now and then. After P2P came to town, it got a lot worse though.
  • My cable modem speed right now is 5,000Mb/sec down, and 1000Mb/sec up. This saturday I get transitioned to "the new improved" Comcast Internet where my download will be capped at 1500Mb/sec and upload a pitiful 128Kb/sec.

    Basically, they can already give me faster speeds but they are artificially capping it. So why would an article that says they could provide even more speed make me hopeful?

  • by SumDeusExMachina ( 318037 ) on Thursday January 31, 2002 @07:23PM (#2934411) Homepage
    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.

  • by timholman ( 71886 ) on Thursday January 31, 2002 @07:25PM (#2934416)
    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.
  • by ( 321932 ) on Thursday January 31, 2002 @07:25PM (#2934421) Homepage Journal
    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.
  • VPNs (Score:2, Insightful)

    by bubblegoose ( 473320 )
    With all that extra bandwidth do you think they'll remove the "Thou shalt not VPN" provisions from their terms of service?
  • ... for those of us using a LAN/NAT to put multiple computers on 1 connection, then the bottleneck on a 10 GBit internet connection will still be our ethernet cards and hubs/switches/routers. And also, for a machine not on a NAT, with the modem inside, would most likely still take an enormous amount of processing power to recieve 10 GBits of data per second. (And to store it somewhere. Most computers have an IDE drive, of which the *fastest* transfer rate is 133 MB(its?) a second, which is another bottle neck even if you have a 1 GBit NIC -- I'm not sure about SCSI)

    So it may sound nice (I agree, I'd love to have it), but a internet connection is only as fast as the slowest link in between Machine A and Machine B. (So on a 10 GBit network, you'd still be capped at the speed of your network card, which is usually only 10 MBits.)

    Not to mention any caps that the ISP sets up (which is already happening on 1.5 MBit cablemodems)
  • by baka_boy ( 171146 ) <> on Thursday January 31, 2002 @07:30PM (#2934448) Homepage
    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.
  • by JoeShmoe ( 90109 ) <> on Thursday January 31, 2002 @07:39PM (#2934500)
    ...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?

    - JoeShmoe

  • by aderusha ( 32235 ) on Thursday January 31, 2002 @07:42PM (#2934517) Homepage
    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....
    • Re:Rainman (Score:2, Informative)

      by anticypher ( 48312 )
      You are not being too nitpicky. Cringely is an idiot^Wjournalist, not an electrical engineer.

      I, too, was cringing when I read the article. He JUST DOESN'T GET IT. Layer 1 is what defines token ring and ethernet, not layer 3 (network addressing). Even if this rainmaker technology wasn't a scam, layer 1 is where you define both the physical medium and the signal modulation that works best with the medium. Changing TV cable modulation would cause tons of knock on effects, with cross channel interference, harmonics, parasitics, and probably Nyquist reflections cancelling out other channels.

      And I know far too much about QAM, as it is used in modems. QAM has existed for decades. It isn't used on cable systems because there is no way to keep the signal clean enough to recover a tight constellation on grungy, up in the air exposed to the elements cable systems. Shannon's limits on recovering signals from noise get slowly pushed back from time to time, but his model is still sound. Its not going to be replaced by wavelets or whatever the scam buzzword of the week is.

      As for costing US$10, HA! The cable companies would have to replace their entire HFC plant, and every repeater, splitter and signal booster to work with signals that filled each 6MHz channel with wall-to-wall noise. Most of the cable companies offering internet have just placed a little piggyback backchannel filter around each of their repeaters to get a single channel back to the HFC headend. They haven't replaced all the repeaters or much of anything, and they still grumble about the cost.

      Nope. rXc deserves to be kicked around for this shameful piece of drivel. And slashdot is just the place to do it :-)

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

      Your pun would be funnier if you spelled his name right.
  • I'm wondering if the cable companies would even bother investing in the equipment to make this possible. Given that the phone companies can't provide any serious competition in this market and the barrier to entry for anybody else to do local loop service is too high, I can't fathom why an incumbent cable company would bother. They already make pretty good money off the services they provide, so why take the financial risk?

    If the average consumer would be willing to pay a premium over their current service to get this upgraded service, it might make sense. But if a large group of consumers isn't willing to pay substantially more, there's no reason to bother unless somebody else is offering a competing service. Since there's nobody capable of that right now, there is no competition and therefor no incentive to innovate.
  • by serps ( 517783 )

    Brand loyalty is nothing against the power of 10X.

    X10's brand loyalty isn't too crash-hot either.

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  • by technopinion ( 469686 ) on Thursday January 31, 2002 @07:57PM (#2934597)
    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...
  • Boy, would I love to have movie channels that show their stuff in HDTV coming in over a regular cable TV hookup, but it ain't gonna happen.

    History has shown that given a choice between transmitting the same number of channels at higher quality and transmitting a larger number of channels at the same quality, broadcasters will choose the latter every time, because they make more money that way.

    We will never, ever see widespread HDTV in the US. We'll be stuck at NTSC resolution for the rest of our lives. Heck, if they could convince people to live with 100x100 digital video streams, they would, just so they could squeeze even more channels out of the same bandwidth. They drool at the idea of 50 million channels of shopping and other crap. Picture quality? What the heck is that?

  • ...of the user experience, that is. There seems to be a lot of discussion around bandwidth limiting, physical storage considerations, etc. Come on, think about this.

    Nobody said you'd be constantly streaming 10Gbps all the time and saving it to disk. To me it's more about how quickly a page downloads, not how much stuff I can download overall. How much time do you spend reading a page vs. downloading it? Take this comments page for example, I would easily spend 5 minutes reading everything. As it is, the page only takes 5 seconds to download, but, if that could be decreased to near instantaneous I'd love it.

    An entire web page and all its related files (even graphic/sound/flash heavy pages) could easily fit in most modern PC's RAM. Stream it all direct to RAM and pop it up on the page? Why save it to disk at all? For your cache? You wouldn't need a cache if you connection were that snappy. And just think, we could actually stream streaming video instead of spooling streaming video... No disk involved.

    I could see ISPs moving away from limiting your instantaneous banwidth (i.e. capping you at 1.5Mb/sec) and moving towards capping your average bandwidth (i.e. 5Gb/hr). I mean, so what if I choose to eat up my hourly bandwidth allocation (say, by downloading several linux distros simulataneously) in 0.5 seconds instead of an hour? (Technical issues of me saving off that much data that fast, aside.) The overall useage from the ISP is the same. OK, so maybe it takes me 2 seconds instead because there are 4 people queued up ahead of me with big downloads. It would still be very snappy in comparison to today's setups.

  • What this means is that they will throw 10x as many people on the same wire. duh...

    Whatever became of the data over power line system that was so cool like a year ago? Did they figure out that it was too expensive?
  • by PhotoGuy ( 189467 ) on Thursday January 31, 2002 @09:02PM (#2934898) Homepage
    To everyone who is claiming the cable company's T1's can't handle it, and so on, I think they're missing the point.

    The cable company has a *ton* of potential bandwidth between their offices and the consumer. Cable modems for an entire provider typically use *one* channel's worth of bandwidth. There is a phenomenal amount of potential bandwidth. The only limit is repeaters and such along the way, which can be upgraded relatively inexpensively.

    And it would make far more sense for them to stream in the movies *once* from the source tot their offices (or even get them in on DVD), and pump them only within the local area, on demand. To T1's, OCX's, etc., involved (except maybe the initial transfer, once per title, if they decide that's the best way to get the initial content).

    There's nothing stopping them from putting their cable modem bandwidth on completely separate bandwidth allocations from their video content.

    • The thing stopping them is many cable headends are just offices with a big 10m dish and enough equipment to take a signal off the dish and pump it with little influence into their coax pipes. Inserting extra stuff into the streams going to Joe Watcher's coax cable costs money in terms of content and equipment. Too many cable offices don't have the space or money to deliver these sorts of services. I read somewhere (I'll try to find the source if you're interested) which says it costs a cable company nearly 3k per customer to upgrade their analog service to digital service. It costs about half that for cable modem service per user but only if the ISP the cable company hooks up with provides the computer equipment and net connection.
  • We need legislation to split provising of packet services (Which can be a licensed monopoly, like a telco) from content services.

    Lots mroe about this []
  • 1024QAM (Score:2, Insightful)

    by $pacemold ( 248347 )
    If a new application, operating system, computer, or piece of networking equipment comes along that has 10 times the performance at the same price or the same performance at one tenth the cost, it doesn't matter who makes it, that product will take the market.
    Rainmaker customers will get 170 megabits-per-second or more. With wavelet modulation filling the entire one gigahertz capacity of coaxial cable at 10 bits-per-hertz, the ultimate capacity of the system is 10 gigabits-per-second for each segmented subnet.

    10 bits-per-hertz sounds like 1024QAM, but to get 170 Mb/s you have to have 17 MHz HDTV channel... Nowdays the plain 256QAM cable modem can get 40 Mb/s on 6 MHz channel, or, in theory, 136 Mb/s on 17 MHz.

    Looks like in reality there's only 25% performance improvement. Cringely, hold the purchase!
    • Re:1024QAM (Score:3, Informative)

      by $pacemold ( 248347 )
      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?
  • Cringley said: Brand loyalty is nothing against the power of 10X.

    I slipped into dyslexia reading that last word -- it appeared, for just a second, that he was talking about the power of pop-under advertising.

  • If this concept is so great, where's the demo? Rainmaker should have demo units built from off the shelf parts in test on some live cable plants. They might be big and expensive, but if their concept works, it's implementable now.

    There's much handwaving on the Rainmaker site. The big claimed advantage of this approach is that it has greater immunity to impulse noise. That's nice, but is that really the limiting factor on data rate now?

  • by Martin S. ( 98249 ) < minus city> on Friday February 01, 2002 @06:57AM (#2936422) Homepage Journal
    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.

    '500 Channel wavelets... Go back to cable... buy this stuff... Who's on first... "
  • Works in principle (Score:2, Insightful)

    by starrmpic ( 167397 )
    I am sure the folks at Rainmaker are extremely accomplished scientists and engineers (Cringley's mistaken remarks about Layer2/Layer3 are no reason to doubt that).

    Having said that, there is a wide gap..change that to massive gap between theory and practise. First and foremost, who (i.e, what service revenue) will pay for the headend equipment. Even the most dynamic of companies is not going to invest in technologies if there isnt a good ROI. Leave alone the fact that cable companies are monopolies within their markets with little real incentive to do anything.

    We could extend this argument further and talk about the studio infrastructure and the back-bone infrastructure required to produce and transmit so many HDTV channels...but lets stick to the technical aspects. Head-end gear is still relatively doable. The real problem lies in the hundreds and hundreds of amplifiers, repeaters and other devices along the cable plant with nuances of their own
    - what frequency spectrum are they able to transmit
    - what snr
    - what does their spacing have to be
    - how clean are the interconnects
    - what is the quality of the cable

    Im sure these questions are still keeping the Rainmaker folks awake at night.

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