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Wireless 10 gigabits/sec data transfer
swedub writes "Lucent Technologies announced a breakthrough technology that eventually will enable business customers and service providers to transmit up to 10 gigabits per second (Gb/s) of information between locations through the air. " They are calling it WaveStar OpticAir. Global Crossing will be doing field testing this December already. This is the first system to actually use Bell Labs dense wave division multiplexing-can I get coverage in my area? But the encryption issues will be interesting, methinks.
Maybe there should be a vaporware category. Please don't take my post as a flame or flamebait, but I am starting to get tired of stories like [company] discovers/invents a new process/technology that may become useful sometime between 1 and 10 years. I just find information that is relevant today to be so much more useful, if there was a vaporware category then I can consider it as such. The same thing goes for game sites that write article after article of previews and rumors and interviews about games that aren't out yet. I guess I prefer to live in the now. I'm just too impatient to constantly be looking forward to the next big thing.
>Also, what kind of redundancy does this thing
>offer? What if something passes in between the
>receiver and transmitter, or the weather is bad?
If a cd-rom doesn't make it, you just walk over, pick it up, and throw it again.
---- "If we have to go on with these damned quantum jumps, then I'm sorry that I ever got involved" - Erwin Schrodinger
One of the first things that I learned about when I was studying the physical layer in network communications were protocols using this type of medium for physical transport. The author of the text (Andrew Tanenbaum, the author of Minix) criticized it for its easy disruption by weather/obstruction/heat. Something that many people seem to fail to consider with this is the refractive qualities of air - although they see the obvious, such as birds and other foreign object flying through the paths of the beams(something the is quite likely to be corrected for in the protocol; any good data protocol will incorporate error correction/detection featers so these types of incidents are made quite irrelevant), they don't seem to see that if there is a substantial difference in the heat between the two points, the air will be different enough to refract the light so it misses the transceiver entirely. Again, if the protocol designers have a clue, they might incorporate some sort of detection/correction (in this case, possibly moving motors in the transceiver to correct for the refraction). Just my two cents worth on this protocol.
-- K
Not really. If there is dust, smog, or rain in the air, a fair amount of the light will scatter. With proper equipment, it wouldn't be too hard to tap the beam.
From the article:
"At this rate, customers will be able to transmit the data contained on 15 CD ROMs through the air in less than a second."
CD capacity is ~600M, right? 15*600 is 9000, or 9G. Isn't 10Gbps, ~1Gbyte/s? Did they confuse GBit and GByte?
On the other hand, either way it's faster than PCI, so I won't be using up all that bandwidth by myself...
A lot of people pointed out that weather can and will mess up an outdoor laser-based network. Given that, I assume that most of the uses for this will be indoors. Think manufacturing plants (Boeing, Ford), conference/concert halls, trading floors, etc. It makes a lot of sense if you want a high-bandwidth rapid-deployment network inside a building with appropriate lines-of-sight. Much easier to install/uninstall than draping cable over or under everything, especially if you need this network for only a few days/weeks.
Kaa
Kaa
Kaa's Law: In any sufficiently large group of people most are idiots.
a) Bad weather? Falling rain/snow, fog, dust clouds, tree leaves, a bird... Poof. Terrible reception.
...
b) Not mobile? One of the big things that radio networks are good for is allowing laptop users to move through the areas of service. Lasers are directed
c) Useless for people needing the high speed link - see a
The way I see this technology working isn't too impressive. It seems to me that it would just link directly into a more conventional network for temporary use when the weather is known (or projected) to be good... The conventional net would then be divided among a large number of users... The distances it carries data can't be great, because as distance increases, the likelihood of an interruption also increases. Also, even tightly focused laser beams become diffuse eventually...
From the way the article presented it, it seems like there would be multiple nodes each feeding data to the next... but then you have to have permission to put a node down on property that you don't own...
The only real use I see for this is for very short term things where laying the lines is too much hassle and 100% uptime isn't particularly important... ie. conferences, expos, etc...
It seems every time I see an article on Slashdot about some new way of laying out networks or how netwoking is changing, the author seems to make an small snide comment about encryption. Look, the fact is that we have solved this problem with IPsec and other tools such as ssh. Who cares if everyone is able to read my traffic, for I am using end-to-end encryption with all hosts that I frequent and send sensitive data to?! As machines capable of using IPsec become more prevelant (and they will now that Windows users finally got their own decent IPsec implementation through PGPnet), these comments will become more and more disinformative.
I guess what I'm trying to say is that these comments are just going to contribute to FUD. The tools to be secure are out there. Use them, for goodness sake.
A DS3 (About 44 Mbps, or 5.5 MByte/sec) runs about $1500 PER MONTH. This gadget is the bandwidth of about 227 of them. The equivalent of 100 times the bandwidth of a 100Mbps ethernet, vs a T3 which is a bit less than half of one.
If it costs a few grand per box, one-time, a company with two or more buildings within line-of-sight of each other but not on contiguous land, in a region with even moderately good weather, might buy them to connect the building LANs, and fall back to a puny T1 (1.5 Mbps) on stormy days. BIG bargain.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
"I work for a small ISP and can say that this just wouldn't be financialy feasable."
Technology like this will eventually crush small ISPs. There is a huge economy of scale in the high-bandwidth ISP business that small ISPs will never achieve. Small ISPs are pretty small much fish in the evaporating modem pool.
Actually, methinks something like this could mutate and eventually kill ISPs altogether because the transport medium is free and unregulated.
If you get enough computer geeks with [quasi-directional] roof-top stations with/and/or localized radio LANs then you could eventually bridge the entire continent on a sub-Internet.
In a perfect fantastic world every building would just be a relaying node one big spanking public network. (Maybe free networking will become the next electric car -- suppressed but it will happen eventually.)
There would be all sorts of neat-o architecture problems too. Fun stuff for the network-design masochist and the script kiddie alike.
The article doesn't say how the bandwidth will fair during bad weather, ie rain storms or blizzards. Methinks this will go the way of personal satellite uplinks - very specialized applications where reliability is less important than cost, speed, etc. 10GB/s is nice, but if it has 10% downtime whats the point?
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That depends on the modulation and mixing schemes that they use. By the time the carrier reaches the output, it's been multiplexed on to one beam, so lining up several emitters shouldn't be necessary.
OTOH, the transmitting and receiving mirrors will have to be aligned very precisely. There are a few ways to do this (even ways to do this automatically). Solving this is picky but not intrinsically difficult.
Come to think of it with that much band width the television / movie bizz has got to be excited. This has got to be cheaper than a satalite uplink and if there is a remote even within the usable range of this tech all they have to do is set up and shoot the video down it.
It would probably wind up being more expensive than satellite for TV broadcasting, actually, because TV is _broadcasting_ - using one (espensive) satellite to send data to many, many homes. The cost of the satellite is amortized over the number of viewers that it serves. A laser link, OTOH, only serves one user.
Where it would be more useful is in transmission of TV data from the master station to other distributing stations, but they already have microwave links in place for this (that's what all of those towers in the countryside with dishes and ariels on them do, among other things). Lasers would give higher bandwidth, but how many cable channels do they want to transmit?
What is the efective range of this anyway?
That depends on several things, but a previous poster said single-digit kilometres (or miles, if you prefer). This sounds reasonable. Haze in the air will scatter the beam after a while even in clear weather.
As another poster already noted, it's 10Gb weather permitting.
;)
Also, it's a line-of-sight technology. I, for one, can't imagine this being used effectively for much more than spanning roadways and other public right-of-way restrictions without the legal hassle of an easement. Maybe jumping over a small river or such, but the morning fog, or the heat rising off the rooftops would just shoot your network to hell...
Cost-wise, I doubt that this will ever be more affordable than traditional fiber. The endpoint hardware has to be at least as expensive, and the cost of fiber vs. the power needed to push light through the air is a major argument in favor of glass/plastic.
My 0.02 euro
-- What you do today will cost you a day of your life.
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"Oh shit, it's raining again!"
Birds are not so much a problem because if it's important, a TCP-like net connection is being used, and retransmissions will occur. Now a whole flock of birds, well...
2) Encryption? Well, it is hard to intercept because you'd have to be in the line-of-sight. Now if you're between the Tx and Rx, you'd probably have a good intercept, but you might ruin the link for the legit user. If you were behind the legit Rx, then that receiver would be blocking you, and you as well might be out of range for the link.
Still, if it's important, the user(s) that need encryption will do so as necessary on their connection(s) only.
3) No good for anything but line-of-sight (LOS)? This is still a big market for data carriers. There's bandwidth all over the place between 2 GHz up to 38 GHz for point-to-point use, and these pretty much have to be LOS-only. At around 28 GHz, there's LMDS, which is point-to-multipoint; still, it's LOS-only (in spite of what some might say).
This laser solution is clearly LOS-only, and will require proper aiming and all that at each end. And, it isn't very mobile, but Navy ships could certainly afford the required autotrack mechanism to make this useful even with gentle rocking of the ship.
Yes, I do this for a living, only at RF.
Anyone who has used a line-of-sight optical system for doing a T1 or something similar knows that this won't work worth crap in a lot of typical outdoor situations.
;-)
I see a couple of good applications.
1) Get the bandwidth up today while you get the trencher out to bury your fiber.
2) Replace the bandwidth today after somebody else cut through your cable trenching in their fiber
3) Use it indoors. Large convention centers could use a couple of these puppies to move lots of data around where fiber runs might not be pratical. Also think of Boeing's assembly plant. VERY large building with pretty decent sight lines without weather problems.
In general though - this is only going to be useful to a far smaller number of people than would use a traditional fibered system.
Ok, I'm going to geek out here for a second...
:) )
It sounds like they intend to use this like point to point microwave, but in areas where microwave isn't feasible. This is becoming more and more of an issue with wireless local loop technology being the current vogue.
The problems with microwaves is that they scatter. Not only do you have to worry about the beam getting to the other end but you also have to worry about all of the reflected signal that will interfere with both ends and any other microwave sites. Plus there is the bleeding of signal out the back... the antenna patterns can be fairly complex and interference analysis is a very big business. Some would argue that the wireless local loop and point to multi-point markets have yet to be adequately addressed. The engineering can get very complicated. Especially if you are talking about small-scale dense areas like campuses and office complexes.
Also, the equipment for microwave is likely to be more of a hassle. If you aren't familiar with it there is a lot more to it than you might think. Compressors to keep the waveguides empty, etc.. (Fiber makes a pretty good waveguide for light.
re: Weather. Light is highly attenuated by water droplets in the air but so are microwaves. This is all part of current reliability analysis when designing microwave links. There are known ways of limiting the affects of this and they might apply to light as well.
It would be interesting to have a reliability/attenuation comparison between microwave beams and light. If only I were a microwave engineer instead of the guy that writes some of their software... I might have more to say.
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Comparing? THEN use THAN.