In the last few weeks, multiple records for fiber networks have been broken, with interesting implications for networks within and between data centers.

It’s only been a few weeks since I looked at the arrival of 100Gbps fiber links in data centers, but there really has been enough going on for another look.

Fiber optic cables
– Thinkstock / Andrey Moisseyev

Record breakers

First, we heard of a fiber speed record. The Hong Kong Polytechnic University (PolyU) sent a 240Gbps signal over a 2km fiber, which is several times faster than available products.

The interesting thing here is that the speed increase wasn’t achieved by using better signalling systems or a higher quality fiber. Those were pretty standard. The team achieved a faster signal by applying new kinds of error correction.

The PolyU team analyzed tons of transmission data, and found the pattern of distortion created by the fiber. They were then able to subtract that pattern from the stream of data detected, leaving a purer signal, that would support a higher data rate. That means this could potentially be applied to lots of existing fiber, increasing the speed available in systems without recabling.

Packing more ports

But there’s still plenty of new cable being put in, either in upgrades or new builds. For those people, we heard of a new cabling system that reckons to pack more fibers into a rack than before. The Reichle & De-Massari high density cabling system can put 120 ports into a single rack unit. That’s impressive, but it also stacks, so R&M were able to show 1080 patch cords going into a space that is 9U high. These are standard MTP or LC duplex connectors, of course, so it doesn’t require a leap into some strange proprietary space.

The name, Netscale, gives you an idea of the kind of customers R&M wants. It’s interesting to see this sort of increase in density, despite the moves we discussed last month, which aim to reduce the number of cables in data centers, by runnning them faster, it seems there’s still a need for ever more cables.

… and packing more fibers 

And finally, we heard of some efforts to increase the packing density in longer distance cable. Italian firm Prysmian has put 2112 fibers into a 24mm sheath producing what it proudly calls the 2112F cable. The first customer was Australian telco TPG, who needed to get as much capacity as possible through an existing 28mm duct under Melbourne’s busy business district, without having to dig and rebury it.

If the PolyU technology eventually gets deployed, then we could eventually see 240Gbps per channel on each fiber. That’s 500 terabits per second on the cable. But that’s only one channel and with DWDM allowig 96 signals per fiber usig different colors, we are well into petabits per second.  

So, even though we’re all going to single mode with 100Gbps links, there’s no hurry, because we can upgrade what is there, and when we do eventually replace it the fibers should be more future proof than ever.

A version of this story appeared on Green Data Center News