
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."
Hooray, 500 channels... (Score:3, Funny)
-h-
Just give me a pipe (Score:3, Insightful)
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.
Re:Hooray, 500 channels... (Score:5, Funny)
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.
Re:Hooray, 500 channels... (Score:3, Funny)
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.
Re:Hooray, 500 channels... (Score:2, Funny)
**
First Post!!!!!! (Score:1)
by stu72 (stu@shelf.dyndns.org) on Thursday January 24, @04:45PM (#2934533)
(User #96650 Info | http://shelf.dyndns.org/~stu/)
What do I win?
(Your message is number 487 in this discussion. This discussion has been archived. No new comments can be posted.)
Re:Hooray, 500 channels... (Score:2)
In my early days of slashdotting, I'm pretty sure I tried a first post or two, just to see what the fuss was about. If you actually dug one up, I'd be impressed. Do you have a link?
If you don't, I'm curious to know why the CID# is the same as the comment I just posted, and why the year is not included in the date, as per usual
Re:Hooray, 500 channels... (Score:2)
The majority of which are music TV channels, PPV channels (over 20 now, or more. . . . ) porn channels (also PPV), or W/NBA channels. (choose, 10 of each. . .
Don't forget the 10 channels reserved for NHL games (WTF?) and numerous other channels.
They are literally running out of things to air.
I guesstimate that at least 1/8th of the channels I get have no programming scheduled for them at any one point in time. Yikes.
I wonder how long it is before every person in the US just gets their own TV channel?
Hell if IPv6 isn't brought into full effect faster, we just may end up using out own personal cable TV station for routing instead! LOL!
Re:Hooray, 500 channels... (Score:2)
I doubt Hughes is making too much money on DirecTV yet. You seem to think that satellites are cheap; "all" you have to do is throw one up there and the cash just starts rolling in.
First of all, launching a comm satellite can cost upwards of twenty or more MILLION dollars for a disposable rocket. Doesn't the shuttle cost like $1 billion per launch to operate? That's just for vehicle delivery, and doesn't count the cost of designing and building [hughespace.com] the bird.
Next, the DirecTV birds are not your normal comm satellites. Their downlink sections are huge. The bird sits 22,500 miles away, and all I need to receive enough signal to be usable is a 18" dish? That satellite is screaming. That costs money. I imagine that the satellites [hughespace.com] cost more than $100 million. Each.
Satellite TV providers are at a disadvantage with respect to cable operators in that they must build out their entire infrastructure before they can sign their first customer. Traditionally, early adoptors of cable pay for the expansion of the covered territory.
Digital satellite radio [hughespace.com] has the same build-out problems and costs. So did Iridium, for that matter. So will Teledesic.
They're not making as much money as you think simply because their initial cash outlay to get started was (ahem) astronomical. I bet they're still working to recoup their initial investment.
My favorite quote... (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?
Re:My favorite quote... (Score:2, Funny)
Re:My favorite quote... (Score:2)
Only if you didn't have the common courtesy to correctly spell his name in your message to him.
C-R-I-N-G-E-L-Y
Re:My favorite quote... (Score:2)
Doesn't Matter (Score:2, Redundant)
Cable modems are already capped. This just
means 10 times more unused potential. There's
no competition forcing providers to open up
those pipes.
Not with Cable companies at the head. (Score:5, Interesting)
Re:Not with Cable companies at the head. (Score:3, Interesting)
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
Re:Not with Cable companies at the head. (Score:3, Insightful)
I'm with Comcast (Score:2)
Re:I'm with Comcast (Score:2)
Try running a web server....
Re:I'm with Comcast (Score:2)
For me Internet is not a TV. I want to run my own server in my house. I can live with dynamic IP, just update dhs.org when the address changes.
Regardless of where the bottleneck is, i don't want my connection being slowed by some idiot who thinks its fun to run a server on his home computer.
A moderately used web server uses a lot less bandwith than any teenager with Gnutella. My entire website today is less than 10Meg.
Internet is a communication medium. "Personnal" Internet should let me communicate with other people...
I don't want to consume "content", I want to create it! For example, I like my email pals in Australia to see some pictures of the snow I took last weekend, or listen to the latest jam session I recorded with my band. I don't want to email these, let them come to my server.
What If I want to get access to my MP3 files at work (so I don't have to carry 200 CDs with me)?
Re:No problem (Score:2)
Technically you are right. The ISP owns the wires. However, imagine that the phone company would not allow usage of modems on their lines. Actually, you don't have to imagine. At one time ATT allowed only ATT approved equipment attached to their phone network. If ATT's monopoly was not broken up, there would be no Internet.
Re:I'm with Comcast (Score:2)
In the case of cable modem or ADSL since you need an IP address for each customer anyway it makes sense to have an IP stay with the customer, unless you make some drastic changes to the way the network is configured, which shouldn't happen very often.
Regardless of where the bottleneck is, i don't want my connection being slowed by some idiot who thinks its fun to run a server on his home computer.
Plenty of things suck more bandwidth than a web server
It's more a case of ISPs trying to copy the kind of setup they used for dialups to cable modem/adsl without considering if this is the best model for a permenantly on type of connection.
This will make little difference... IF not be WORS (Score:2, Insightful)
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?
Re:This will make little difference... IF not be W (Score:2)
Similarly, if traffic prioritizing is done decently, the fact that some clients have faster local connection shouldn't make situation worse for those with slower connection. So, faster cable modems shouldn't necessarily make it harder for others, provided capacity is fairly shared, not by end systems but by routers doing QoS queuing.
You've hit the problem a lot of the High Speed ISPs are facing - backend provisioning a high speed network.
Sympatico [www.bell.ca] used to (and seems to still be) provisioning thier Central Offices with a single T1, so your 968K connection would get choked as soon as more than 20 people were connected to the same CO. I was just speaking to someone with thier DSL service and they explained that it gets slower during peak hours (so much for thier "Always fast!" advertising angle
QoS is a possible solution, but it could get un-weildy very quickly, especially if it's not secured properly. (Dude, I hax0red the Cisco and now I reseverd myself the whole pipe! I am l337!) A better solution would be to make sure the backend can handle more than the capacity of all the frontend pipes aggregated in order to keep QoS exposure to a minimum.
Soko
Is this another 100 mpg Carbeuator? (Score:2, Funny)
Wavelets wash back (Score:4, Insightful)
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.
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.
Re:Wavelets wash back (Score:5, Insightful)
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.
Re:Wavelets wash back (Score:2, Informative)
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.
Re:Wavelets wash back (Score:2)
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...
Re:Wavelets wash back (Score:2)
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?
Technology is nice, but... (Score:2, Interesting)
When I look at where we are headed, sometimes I just get more and more depressed.
Jason
I don’t see how this helps anything (Score:5, Insightful)
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.
Re:I don’t see how this helps anything (Score:2)
What's The Point (for cable modems)? (Score:5, Insightful)
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.
Re:What's The Point (for cable modems)? (Score:2, Insightful)
Here in New Zealand the main form of fast 'net access is ADSL. There are other systems, like the recently-featured CityLink [citylink.co.nz], 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 [getultra.co.nz]), 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 [xtra.co.nz], the ISP associated with the local telecommunications monopoly [telecom.co.nz], 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 [jetstream.co.nz], 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!
Re:What's The Point (for cable modems)? (Score:2, Interesting)
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.
Re:What's The Point (for cable modems)? (Score:2)
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.
Re:What's The Point (for cable modems)? (Score:2)
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)
I wonder what the ratio of katz-ignoring-slashdotters vs cringley-article-hits is.
Re:Hey Taco (Score:2)
Re:Hey Taco (Score:2)
Re:Hey Taco (Score:2)
Gary? Is that you?
;-)
Re:Hey Taco (Score:5, Funny)
"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."
Re:Hey Taco (Score:2)
I've had Katz on ignore for almost a year now.
Still I don't think Cringely needs to stoop to
It will never happen! (Score:2)
Sounds like what happened with modems (Score:5, Informative)
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.
Re:Sounds like what happened with modems (Score:2, Informative)
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.
Modems are maxed out (Score:5, Insightful)
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.
Baud rates (Score:2)
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.
Re:Sounds like what happened with modems (Score:2)
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.
Cable TV doesn't work well with reflections either (Score:2)
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)
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.
They won't improve cable modems. (Score:3, Insightful)
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 $10/month you pay for renting the modem, which doesn't sit well in a business plan.
Re:They won't improve cable modems. (Score:2, Interesting)
You got them pegged.
I live in one of the pilot cable modem towns... Like the 4th nationwide to get cable modem service. I first used cable Internet around 1995, our high school got one.
They still have the ancient Zenith modems in service, and just a couple months ago started to move to DOCSIS.
The old modems had no rate limiting capabilities, so anyone could saturate the T1 they had to the Internet (it's a small town with not many geeks, so they can get by with a single tier 1 T1 and some peering T1s to their other locations nearby).
Anyway, they talked about migration to DOCSIS for the last 3 years, and they are just getting around to it. Cable modem companies are really resistant to changing the customer hardware.
One good think about those old Zenith modems though, was they were like an ethernet hub, you could see the activity and collisions on the cable side. That also gave away their secret that the collision light stayed on without flickering at all from 10:30 am until 8pm.
Somehow you could still pull down around 30KB/sec every now and then. After P2P came to town, it got a lot worse though.
So what, they will still cap us... (Score:2)
Basically, they can already give me faster speeds but they are artificially capping it. So why would an article that says they could provide even more speed make me hopeful?
Re: (Score:2)
Re:So what, they will still cap us... (Score:2)
This time it's you. The poster said 1,000Mb. That's a gigbit pipe. He meant (I assume!) either 1Mb or 1000Kb.
Re:So what, they will still cap us... (Score:2)
Jeremy
What a fucking shill (Score:4, Troll)
Really, does this guy have any shame? And what's all this about astroturfing for M$'s .NET initiative? It really isn't all that great, dude. You're just a marketing dupe.
Anyone remember Transmeta? (Score:5, Insightful)
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.
Blatent Karma Whoring Link (Score:4, Funny)
You got to wonder if this is one of the SEC [slashdot.org] sites.
VPNs (Score:2, Insightful)
Bandwidth is nice, but... (Score:2)
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)
Cringley's weak spot (Score:3, Insightful)
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
I don't mean to sound snide but... (Score:5, Insightful)
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
.
Cringley and the OSI model (Score:5, Informative)
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)
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
Re:Rainman (Score:2)
Re:Cringley and the OSI model (Score:2)
Your pun would be funnier if you spelled his name right.
Will they bother? (Score:2)
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.
Brand Loyalty? (Score:2, Funny)
Brand loyalty is nothing against the power of 10X.
X10's brand loyalty isn't too crash-hot either.
I'll sell ya a product (Score:2)
Cablemodems can already be much faster than we get (Score:4, Informative)
Re:Cablemodems can already be much faster than we (Score:2)
Easy! We just sell 'em about a dozen of these new Rainmaker chip thingies, and then they can install them in series on their phat pipe! Man that would rock!!
Re:Cablemodems can already be much faster than we (Score:2)
HDTV my ass (Score:2)
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?
Think quality not quantity... (Score:2, Informative)
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.
More bandwidth? I think not (Score:2)
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?
Local delivery, not backbone'd, I'd guess (Score:4, Insightful)
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.
-me
Re:Local delivery, not backbone'd, I'd guess (Score:3, Informative)
Re:Local delivery, not backbone'd, I'd guess (Score:2)
Even 50 people, at $30/month, 12 months a year, is $20K/year, for a relatively small investment. Even with one-time head-end and trunk stuff, it's still a real money maker.
As the denisty goes up (as in San Jose), so should the profits. Yes, you need more switching locally, yes you need more high-end head-end stuff, but that's only because there's a shitload more people willing to pay you hundreds a year for that service. Believe me, it pays. If it doesn't, it's because of some other flaw in their infrastructure (a half dozen execs drawing half-million salaries, and such
-me
Good solution to the wrong problem (Score:2)
Lots mroe about this [blogspot.com]
1024QAM (Score:2, Insightful)
Re:1024QAM (Score:3, Informative)
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 quote (Score:2, Funny)
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.
Where's the demo? (Score:2)
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?
Cable is wrong topology (Score:3, Insightful)
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.
I've gotta say it! (Score:2)
'500 Channel wavelets... Go back to cable... buy this stuff... Who's on first... "
Works in principle (Score:2, Insightful)
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.
Re:Calculus (Score:1, Funny)
Re:Great! (Score:2)
Re:Great! (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 [freesoft.org] pretty much covers it. I'll quote the most relevant bits:
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.)
--JoeRe:Great! (Score:5, Informative)
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.)
Re:Great! (Score:2)
This sounds eerily familiar... (Score:2)
http://www.terayon.com/cat.html?cat_id=9.1.1.2 [terayon.com]
Anyway, this is what my benighted cable system uses to give us cable modem without the muss, fuss and bother of installing modern fiber-optic plant. Believe me, it isn't very fun.
Maybe they can squeeze more speed out of the wires. Maybe. But you're going to suffer for it with lowered reliability. When you have to powercycle your cable modem every day to make sure you've got connectivity something is VERY, VERY WRONG.
Re:Screw speed (Score:2, Interesting)
Re:Boost or stomp cable providers? (Score:3, Insightful)
I would say that this is exactly what they are looking for. It gives them:
Re:Can anyone explain wavelets? (Score:5, Informative)
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
Yes! (Score:2)
In addition, the government has proved that wavelets, when properly applied, are responsible for keeping George Washington alive all these years in a secret location.
Since your a wireless engineer, I take it you know how the Fourier series and transform works - the ultimate idea is that a series of circular functions of various frequency, amplitude, and phase (sines or cosine functions).
Wavelets work similarly, except that instead of sines or cosines as the basis, a bandwidth limited function, such as rect (not used that often) is used as the basis for the series. There are a few obvious advantages to this (there are some other not quite so obvious ones that I won't get into).
1) Different basis functions can be chosen for different domains based upon which function most compactly represents the desired signal. (For example, it is impossible to perfectly represent a triangular wave by Fourier transform, but quite possible with some wavelets).
2) More data can be fit into a single stream since all the waves are localized (unlike sine and cosine, which are infinite).
The long and short of it is that it is a very good frequency transform.
Re:Attn Investors! (Score:2, Funny)
profits will rise as time goes on.
hopefully the smaller (if they still exist) cable companies will go for this first, forcing the big guys too, so as to offer something "better" than that no-name competition down the street.
maybe
AuDSL (Score:2)