How Google uses mirrors to dynamically reconfigure its networks

Google has scaled its network capacity from over one petabit per second to beyond six petabits per second since 2015, and some of that growth has come from switches that bounce optical signals off an array of mirrors to redirect traffic. As our sibling site The Next Platform reported in 2015, Google calls its datacenter …

[Gene Cash]

Dynamically

Are you saying this is done dynamically?

[Francis Boyle]

Holy pleonasm Batman

It's so dynamic even the Dynamic Duo would be dynamically envious.

[Alan J. Wylie]

An old patent: "Device for controlling a light beam"

That reminds me of this patent from 1968.

Otto Frisch founded the first company I worked for after leaving University.

[Dinanziame]

My mind is full of questions, but mainly I want to know why the number is 136.

[FILE_ID.DIZ]

A common fiber bundle size is 144. Perhaps 136 is used for production, the remainder is for spares or used in out-of-plane management comms?

No real clue, however... just a guess.

[Tom66]

How Google uses mirrors dynamically reconfigure its networks dynamically,

As opposed to dynamically reconfiguring its networks statically?

[diodesign]

Re: How Google uses mirrors dynamically reconfigure its networks dynamically,

Don't worry, we fired the AI bot that wrote that headline into /dev/null

It's fixed - don't forget to email [e-mail] if you spot something wrong.

C.

[zuckzuckgo]

I always suspected that Google was just smoke and mirrors. Now we just need to identify the smoke.

[aregross]

Don't drop it!

I imagine there's an alignment procedure done, either 'dynamically' or manually.

How big (or small) are these mirrors? With only 136 fibres involved each I can't imagine them being very big.

[Roger Greenwood]

So in the future...

...when I say I can't see the network, it will literally be true!

[BlueJay]

Re-inventing

I'm not sure what's new here that wasn't already achieved by photonic switches? Some Internet exchange points have been doing this since at least 2004, but maybe without the beta tag...

[diodesign]

Re: Re-inventing

Yeah, but the improvements are interesting.

Well, we found them interesting. Cutting-edge network experts may not be impressed.

C.

[Anonymous Coward]

Re: Re-inventing

I found it interesting as well and I thank you for highlighting it. A pint for you and the Google boffins.

[martinusher]

They're just optical switches

They're components you can buy, they've been on sale for a decade or more. They're like small blocks that you connect fibers to that you switch using a voltage (think "optical relays"). Its likely that the 2022 version is rather more sophisticated -- and dense -- than the 2006 version.

There are situations where physical connectivity rather than logical connectivity is useful, especially if you need to isolate circuits or you're working with optical data and you don't need to switch circuits packet by packet.

[diodesign]

More sophisticated and dense

Yeah that's it - it's just rad to see it detailed at Google-scale. See the paper for more info.

C.