
The secret world of microwave networks - okket
http://arstechnica.co.uk/information-technology/2016/11/private-microwave-networks-financial-hft/
======
ocfnash
The emphasis on secrecy is rather overblown IMHO: there's an entire company
(not mentioned in the article!) whose sole business is building/maintaining
these networks and they make plenty of information public on their website
[http://www.mckay-brothers.com/product-page/](http://www.mckay-
brothers.com/product-page/)

~~~
xhrpost
I remember reading in a book once that during the cold war, the Soviets used
microwave communication partially to get around the Allies snooping on their
RF communications. So, the Allies would position satellites such that they
were in the line of sight of the microwave links so they could listen in on
the extra transmissions that overshot the receiving end.

~~~
dom0
This was also a popular technique to intercept microwave links on the ground.

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mxuribe
I so very much enjoy these kinds of stories. Even if there is debate over the
actual speeds, etc., the general info is great to learn about! This is the
kind of stuff that I show to my pre-teen daughter, so that she can see that
there are wondrous, technical things going on all around us; that to some kids
might seem fantastical and bordering on science fiction. And hey, if she ends
up going into a STEM-related career because of exposure to these cool types of
articles, that's not so bad either. ;-)

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ramanan
For those interested in the use of microwave links for HFT, there was an
interesting post [1] a while back and some discussion on HN [2] too.

[1] [https://sniperinmahwah.wordpress.com/2014/09/22/hft-in-my-
ba...](https://sniperinmahwah.wordpress.com/2014/09/22/hft-in-my-backyard-
part-i/)

[2]
[https://news.ycombinator.com/item?id=8354278](https://news.ycombinator.com/item?id=8354278)

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makmanalp
So back in the day, perhaps over a decade ago, I remember stumbling upon a
textfile that was along the lines of "interesting IP addresses on the net"
(does anyone know what I'm talking about? I can't find it since.) and one of
them was a very curious telnet console that had all sorts of settings.
Googling the terms, it looked like it was the control panel for a microwave
antenna. I was too scared to mess with it though. I only remember exploring
through the menu options. I never figured out where it was or what it did, but
I remember it was surprising to me at the time that standalone hardware would
have a telnet terminal.

~~~
redbeard0x0a
Fast forward to today and we have a huge multitude of IoT devices with telnet
interfaces (a ton of webcams) and default (and hardcoded) passwords... Now we
have the Mirai botnet...

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youngtaff
The article talks about tethered barges for a transatlantic link…

How would that work when the dishes need to be pointed at each other and the
barge will be bobbing back and forth?

Does the signal spread enough to cope with that?

~~~
noonespecial
It would probably be more like a large vertical tower with most of its mass
floating underwater than a flat barge with an antenna mast on the deck. This
would mean even large waves would hardly affect it.

The bigger problem is you'd need at least 70 of them to cross the atlantic.

~~~
tshannon
> The bigger problem is you'd need at least 70 of them to cross the atlantic.

That actually doesn't sound too bad. I would've expected that number to be
much higher.

I wonder how that cost would compare to the thousands of miles of cabling we
currently use.

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stompin
To answer the question "why use your own microwave network?" the author
provides 2 reasons:

> The first reason is somewhat obvious; if you have your own network
> connection, it's usually easier to guarantee things like security, quality
> of service, bandwidth, and other factors that businesses value highly. The
> second reason, as we've already alluded to, is that microwave
> networks—somewhat surprisingly—can have lower latency than fibre. With some
> advanced networks, that latency is only a few microseconds slower than the
> speed of light. Fibre can be pretty quick over short stretches, but it soon
> starts lagging over longer distances, such as between two stock exchanges or
> a multinational's offices.

The 1st reason is really off the mark. We know how to securely transmit data
over insecure networks, and quality of service and bandwidth can be better
handled by service contracts with the network provider. He states "other
factors that businesses value highly" which is vague but could possibly be
interpreted to include competitive advantages - yet cannot in light of the
fact that the 2nd point addresses competitive advantages. By owning the
fastest microwave network, you can execute faster than your competitors and
directly use that for monetary advantage. So his 1st reason is completely
waste of space.

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farva
All this effort put into making low latency networks and what are they used
for? Uselessly siphoning money and destabilizing markets.

~~~
chillingeffect
I'd personally like to see the effort put into telesurgery.

~~~
agumonkey
Reminds me of this TED talk by C.Mohr
[https://www.youtube.com/watch?v=Q4ZFud69hfc](https://www.youtube.com/watch?v=Q4ZFud69hfc)

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stompin
> "One proposed method of stopping incidents like the Knightmare, and
> generally to limit HFT from wading too far into ethically grey areas, is by
> leveraging blockchain tech. For example, front-running—sneaking in trades a
> few microseconds early based on advance knowledge of pending changes to the
> market—could be stymied if the market adopted a slightly slower,
> transactional, blockchain-style ledger."

Adding another layer does not stymie anything - it might add latency but this
will be exploited by those with the most resources resulting in [additional]
advantages (e.g. on top of the microwave network advantage, a race to write to
the blockchain).

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PaulHoule
The refractive index of optic fiber is in the 1.4 or 1.5 range which means
light travels at 0.66-0.71c. Said refractive index for radio waves is
practically 1 in the troposphere so microwaves outrace light.

With recent work in millimeter wave radios I am sure you could get the
capacity of this network much higher than it is now, although rain fading
might be a problem.

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leeoniya
last graphic is from
[http://www.submarinecablemap.com/](http://www.submarinecablemap.com/)

------
chrishacken
.

~~~
chiph
The microwave transmissions stay in the analog realm to get their signal
boosted at the intermediate towers, so you don't lose time in D/A-A/D sampling
conversions like in the typical fiber signal booster (there are optical signal
boosters for fiber under development).

~~~
Hikikomori
Optical amplifiers has been the standard for quite a few years already,
especially for long haul dwdm.

