Scientists Double Optical Fiber Transmission Capacity

ms writes: "Yesterday golem.de reported that the Optical Communication and High-Frequency Engineering Group at the University of Paderborn (Germany) claims to have made a technology practical which doubles the transmission capacity of optical fibers to 80 GBit/s. In their so-called "polarization division multiplex data transmission system" they don't only send one but two mutually orthogonal light waves through the fiber. They say the only big problem was the dispersal of the light waves which limits the data rate. Additional they had to fight against the phenomena that the polarization direction of the light waves changes while it goes through the fiber. Now, after two years of research, they invented an "automatic optical compensator of polarization mode dispersion" which fights both the limitations. With this gadget they were able to send data at a rate of twice 40 GBit/s (that's 85,899,345,920 Bps) over a test-line of 212 km. And "only the available equipment limited distance and data rate". As we all know, optical fibers build the (cronically overloaded) backbone of our beloved Net. (BTW: That's Net., not .Net!)" Here's the babelfish translation, too.

Comments

Mind Blown

[Zen Mastuh]

Just trying to grok "mutually orthogonal". Is that redundant, or just over my head? Not trying to nitpick, but to understand something my networking prof never explained.

Dark fiber

[Foxxz]

This is going to help the industry alot. Right now there is pleanty of unused fiber, but the problem is the devices that use the fiber take too much room. if we build them smaller and faster we can increase capacity easily.

-Foxxz

Re:Increasing capacity; increasing vulnerablility

[sllort]

All too often a clueless construction worker rips up a section of fiber and causes some havok.

The industry euphimism for this phenomenon is a "backhoe failure". Metro fiberoptics are all deployed in a "ring" configuration - if a ring is cut, the traffic is sent the other direction on the ring withing 50 milliseconds. The operative protocol here is called SONET. SONET rings have been around for a long time, and they pretty much solve the issue of backhoe failures. Some vendors are pushing proprietary mesh-based architectures which offer even more redundancy.

The issue you bring up, however, does exist on one-way long-haul fiberoptic lines. Major carriers spend millions on 24 hour overflights by patrol helicopters to monitor these fibers for cuts - and some of the largest players in the telco field are oil suppliers because they already patrol their oil pipelines for just this kind of event; burying fiber next to the pipeline is cheap by comparison.

The massive transmission capabilities introduced by advances in fiberoptics DO give us more ability to heal networks, because they give us additional load-bearing capability during failure. The missing piece is actually building equipment which will heal the network effectively, in time. If you're truly interested in ongoing research in this area, open up google and ask it about "GMPLS".

Enjoy.

Capacity is great; Management is better

[tdogboy]

Making bigger and bigger pipes is the way of the net. The technology just has to get better by making the rates higher and the packages smaller.

The next question is, what do we do with all this new capacity? The telecommunications industry is finding all this out since so much infrastructure was built during the boom and everything went bust. There was so much infrastructure out there that was completely useless (think dark fiber) because of incomplete implementation.

They put plenty of fiber in the ground and run out of money before they can get any equipment to light it up. They put plenty of DWDM equipment to light the fiber but they can't sell a whole OC-48 to anyone at a competitive price. They get tons of metro networking equipment but they've just spent all their money and can't make a management system to turn up any metro circuits.

So, these kinds of technological improvements are the greatest thing in the world and they have to keep pushing the envelope. However, there must be concurrent development along all other lines to manage all these ass-kicking boxes and make them usable! If not, no one will buy it because it can't contribute to a sustainable business model.