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I was wondering where the Google servers reside and how their DNS lookup work. I'm located in Germany right now. If I'm calling google.de (German Google page) is the server located in Germany for all the searches or are they splitted throughout the world? If I'm calling google.com, does it automatically connect to the US servers or does it try to look for the search results on a German server first?

I was wondering, because I noticed the really low latency when pinging google.com. I can't imagine such low ping, if the servers reside outside of Germany.

So, how does the lookup of a search keyword works, concerning connecting to their servers? I tried traceroute, but couldn't make up much. Does it depend on the keyword? Does it depend on several different factors, which server is actually being used?

cherrun
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  • you can also use `tracert` instead of `ping`, it will give you a lot more information. You will know which servers you got through to reach the target page. – vsz Mar 16 '12 at 17:18
  • Yes, I could probably use traceroute or tracert with specific search terms. Could make a nice graph out of different search terms. – cherrun Mar 16 '12 at 18:22

3 Answers3

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How Google search actually works is, of course, a closely-guarded secret.

However, in the past there has been some info coming out of them with general practices they employ.

First off, Google has hundreds of datacenters - back in 2008-ish, they were already estimated to run on several hundred thousand servers; you can safely assume they have more than a million now - and that's not counting the new 800-thousand-server datacenter they're building out in the nevada desert :)

These are not necessarily state-of-the-art servers - their platform is "cloud"-ed by its very design, and any number of nodes may die without the slightest detectable change in service.

Basically, they have servers in three tiers: frontend search, middle layer, and backend ("deep") storage.
For every single bit of information google search can provide, the information will be stored in several places - oft-used results perhaps in hundreds of places.
While most of these will use close-by servers to provide answers, they don't have to - if you are searching for a very obscure but specific piece of information, they may have to reach out to one of a few servers that has that piece worldwide.

For daily news (for example), it'll be on thousands of servers, and you will get the closest one.

Search on Youtube for some google architecture videos; I remember this being online some years back.

adaptr
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They probably have multiple datacenters in every continent, and thanks to anycasting they can announce the same networks from multiple providers/datacenters.

You will always go the least expensive path (in terms of as paths, hops, metrics, bandwidth between peers etc etc), therefor you will experience low latency from everywhere.

You can read more about anycasting here: http://en.wikipedia.org/wiki/Anycast

3molo
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The closest DNS entry that returns you request, records differ from Google.de, Goggle.fr and .com this works in your favor so you access the service with less network hops,

However apart from the large google DC's the severs that you and I connect to are most probally GGC (Google Global Cache) servers. They are located at large network POP's and ISP's of almost all teirs. You could say they are a CDN in some way

You can find out more on their GGC Beta program http://ggcadmin.google.com/ggc

btw.. even though it's BETA program, it's far from a Beta deployment ;)

Darragh
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  • Thanks! You led me to the right page for expanding http://security.stackexchange.com/a/121421/49489 – Ángel Apr 25 '16 at 20:49