

Fiber cables made of air move data at 99.7 percent the speed of light - bcl
http://arstechnica.com/information-technology/2013/03/fiber-cables-made-of-air-move-data-at-99-7-percent-the-speed-of-light/

======
michael_miller
My guess is that the first customers for this cable will be in the finance
industry. A 30% improvement in latency doesn't matter much for the layman, but
in finance, it can mean significant amounts of money. Already, an enterprising
trader constructed a more direct line from Chicago -> NYC [1]. Going from 16ms
-> 13ms was apparently worth $300 million. This fiber could bring a very large
profit if you had exclusive rights to it via a patent. You could execute
guaranteed-to-profit arbitrage strategies between any two markets if you were
willing to build out the network. And no one could compete with you for a
whole 15 years!

[1] [http://www.forbes.com/forbes/2010/0927/outfront-netscape-
jim...](http://www.forbes.com/forbes/2010/0927/outfront-netscape-jim-
barksdale-daniel-spivey-wall-street-speed-war.html)

~~~
namwen
Wasn't this mostly stopped in NY when the Exchange set up a server building
and allowed firms equal access? They had been buying up the real estate around
the exchange for amounts much high than the property's value and it was
becoming a bit of a problem. Now they are all in the same building and
everyone has the exact same amount of cable running from their server to the
exchange.

~~~
evanb
This move halted the land rush around the fiber access points in New York. But
suppose a firm trades both on the NYSE and CHX in Chicago. If there's a price
difference on the same stock in the two exchanges, you can buy low and sell
high for a brief period (a few ms): if your machines in the NYSE building and
CHX building can communicate that price difference faster than anybody else,
nobody knows there's a discrepancy to be taken advantage of.

------
andymoe
As an aside, if this is rolled out widely, can we finally come to terms with
the genius of Senator Ted Stevens metaphor about the internet being a "Series
of tubes." :)

<http://en.wikipedia.org/wiki/Series_of_tubes>

~~~
josh2600
People make fun of this remark all the time, but the Internet is a series of
tubes filled with glass...

~~~
mtowle
Half correct. Yes, people used to make fun of the comment all the time. But
the only sentiment anyone has submitted on the topic in at least last 5 years
is the exact thing you just said.

------
peeters
> Researchers say they have created fiber cables that can move data at 99.7
> percent of the speed of light, all but eliminating the latency plaguing
> standard fiber technology.

If by "all but eliminating" they mean "reducing by 31%".

There's a hard limit to how low latency can go. We've been close to it for
years. So a hop takes 100 ms instead of 150 ms? They're still in the same
ballpark. To have a revolutionary impact, it would have to drop the latency an
order of magnitude, which, as far as we understand our universe, is
impossible.

I guess the real application is over short distances. I'd love to hear the
ideal usecase that benefits from this improvement.

~~~
hhw
The problem with this technology is that at a 3.5dB/KM loss, it's only really
good for about 10KM. At such short distances, the latency difference would
only be about 0.0167ms. Given all the other latencies involved between two
end-to-end hosts, that's hardly worth laying new fiber for. Unless they manage
to reduce the loss to within a reasonably small multiple of more traditional
fiber, this new technology isn't going to have much adoption.

At only 37 channels, compared to the 80 that more traditional fiber can carry
using DWDM, it also carries less than half the capacity. And that's assuming
that it's capable of the same bandwidth capacity per channel; the article
states 40Gbps per channel, whereas you can already go as high as 100Gbps over
a single wave using DWDM, which means it may only be able to carry 18.5% as
much.

~~~
aortega
Also, I don't see this technology being compatible with erbium-doped fiber
amplifiers. See, even the best glass fiber is good only up to 80 km, that's
not enough, but by placing a piece of erbium-doped fiber it acts as a laser-
amplifier and the fiber lenght can go up to 4000 km. Now that's useful. IMHO
the EDFA is the technology that really enabled high-speed internet.

~~~
alokv28
Why couldn't these fibres work with EDFAs? As long as the fibres are designed
to operate in the C-band (~1.55 micron wavelength), there shouldn't be a
problem running them through an amplifier.

~~~
aortega
No physicist here but I think there may be losses in the interface air/glass.
Also, air contains water and other elements that may present too much
attenuation at 1550 nm. I suspect the different lambda is one of the reasons
of the limited bandwidth of the hollow fiber. I should try to RTFA.

~~~
timthorn
It's overcoming the losses in the interfacing that's the innovation here -
holey fibres have been around for a while. Note that it's the same research
lab doing this work as invented the EDFA in the first place.

------
hakunin
Financial field isn't the only one that cares about latency. I'm still waiting
for it to become feasible to jam (play music together) remotely. This gives me
hope, but the real solution is still far away. Interesting how despite all the
tech progress this (deceivingly simple) problem is still unsolved.

~~~
notatoad
no, there's lots of applications for low-latency connections. the reason
algorithmic trading is special is that the financial people are the ones who
have a valid business case for installing low-latency connections. is it worth
a couple of billion dollars for you to jam remotely?

~~~
dfox
Few years ago the main business case for low latency was telephony. And that
is the reason why there is/was so much inertia with replacing various frame
based TDM/SDH/SoNET systems with packet based solutions (this was whole reason
why ATM was developed as it is sort of in between of these extremes but still
does not have latency and QoS characteristics that were originally sought).

These systems are designed to either induce constant latency (TDM, one frame
period per switch) or induce lowest possible latency (SoNET/SDH with very
clever mechanism to construct frames without knowing their full content and
decoding them incrementally, which gives best case latency of few bit times +
latency of any fiber interface, worst case comparable with traditional TDM).

The problem with latency and telephony is two fold: echo cancellation for
single pair analog phones (phone itself only substracts outgoing signal from
incoming so anything that is echoed from other side of line goes through) and
maximal latency for comfortable conversation (which is surprisingly small).
First problem can be solved with smarter interfaces that do echo-cancellation
in some DSP (some kind of license for doing that is major part of cost of
analog interface cards for open source PC based softswitches), second not so
much.

So in all you can reasonably jam remotely (on distances of say less than
2000km) using this infrastructure and using it is probably few orders of
magnitude cheaper (renting channels in SDH/SoNET optical networks is actually
surprisingly cheap) than laying special fibres.

------
scottstephens
Laying this new fiber would probably be economically viable for low latency
trading. They're already building microwave networks to take advantage of the
spread between speed of light in air and glass
([http://www.securitiestechnologymonitor.com/news/mckay-
brothe...](http://www.securitiestechnologymonitor.com/news/mckay-brothers-
spread-networks-chicago-new-york-29829-1.html)). Based on the fact that most
long haul networks use fiber rather than microwave, I would assume that fiber
is more economical than microwave.

------
undefuser
Woohoo, low latency counter strike from Asia to US!

