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Using IR Lasers Instead of Fiber
Artifice_Eternity writes: "Can't deal with the trouble, time or expense of digging up the street to get fiberoptic cable to your building in the big city? There's another way...infrared line-of-sight infrared lasers between your building and another one nearby. Repeaters and redundancy can keep the chain going reliably for miles, with gigabit data transmission rates."
This is good for many reasons. The cost is
primarily in the one time purchase of the equipment. And it makes a lot of sense where line of sight is a shorter distance than a fibre cable must travel (tops of buildings in a congested city). These dont interfere with radio freqencies, so you don't have to concern yourself with noise, or creating noise. And its unlikely a backhoe will ever be a problem (as long as it doesn't block the line of sight).
The downside is the line of sight. You ALWAYS have to have line of sight. Rain, fog, clouds, trees, idiots with signs, they all can cause problems. Short distances are less of a concern, but you still have to maintain an almost perfect orientation. A little gust of wind can have you dropping packets.
But its probably a better solution than fibre where running fibre isn't an economically feasable solution. But no matter how good this is, fibre has far greater potential capacity, even though we don't yet have the technology to use all of it. It doesn't make sense to start building the internet backbone out of these things.
-Restil
Play with my webcams and lights here
Infrared line-of-sight links have been done for well over a decade. Datapoint's Arcnet had an infrared link device called Arclight that they used for a line-of-sight link for several miles. It would flake out in rain or fog - because rain and fog both absorb and refract infrared. So it might as well have been as opaque as black smoke.
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Arcnet was a self-healing token ring network with an underlying broadcast topology. So if two buildings were connected by Arclight and it went down, the network split into two rings, and when it came back up it healed into a single ring. Reconfig took miliseconds so it was no big deal.
You may not have heard of Datapoint. But have probably heard of the Intel. Seems Datapoint had a discrete-component standalone computer/smart terminal which was the basic node in their network - a diskless-workstation, fileserver, compute-server archetecture. They cut a deal with a semiconductor company called Intel to try to port their instruction set to a silicon chip for the next generation. But the resulting chip was too slow, so they went with another discrete component solution.
And Intel had cut the deal so they could sell the chip. So they took the chip to market, perhaps with a few tweaks, as the 8008 - first in the line that continued with the 8080, 8086, 80x86, Pentium,
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Yes, as many have commented this is old news. There haven't been any breakthroughs on this in several years. Let me rephrase that ... no significant breakthroughs.
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Once a year we have a customer come to us to ask about this option. Once a year we trot out our proposal, rerun the numbers and submit it. It always comes down to two things:
1) Speed
2) Reliability
The speed of the lines is fantastic when you have a clear day and relative distance is kept. Any atmoshperic conditions out of the ordinary will kill the line. Now, if you're only interested in using it for a mail gateway or to transfer data for a nightly batch cycle it rocks. For regular WAN access you'll be answering the phone from the folks on the floor.
Reliability is a concern past the speed. Keeping the connections is sometimes more an art than science. The article does have an interesting take on parallel transmissions, but commerically available products are cost prohibitive to make it a viable alternative for most businesses.
The best line from the article is: "Transmitting lasers through the air and modulating them at gigabit rates is a new and potentially powerful development," said Dr. Daniel Leslie, a physicist at Trex Enterprises who is familiar with the new systems.
Now, if you want to see something cool check out Dr. Leslie's company web page: http://www.trexenterprises.com/laserrad.html
If only we could work a Pringles can into this