Google Dance. About Google datacenters

Now in a network it is possible to find many services offering to estimate Page Rank your site on 40-50-100-etc. from Google search engine datacenters. Whence these services take the information about datacenters? And how many it (datacenters) in general?

IP addressing Google

Having reflected on this subject, I have decided study it ... Whence to start basically? Probably the most simple way - for the beginning to estimate how many in general IP addresses belongs to company Google Inc?

Perhaps the most full (on 01.11.2006) their list:

Let's reflect now - if you have suddenly decided buy for the own internet project allocated IP address - unless you place begin necessarily on it a Google datacenter? I think no. Hence and such big company as Google IP addresses uses not only for the organization datacenters... At them enough other services and requirements. Except for that hardly it is possible assume that company Google (in which by way programmers and mathematics work) contains such enormous address space in the disorder... Order for certain is. Hence we should study only small amount IP addresses from the given list and most likely they are obliged to have the identical ending, for example at addressing: AAA.BBB.CCC.DDD, at all datacenters IP addresses of class DDD should be identical. And thus all services Google within the framework of one address space of class CCC, should use (theoretically) and return that value Page Rank which informs them datacenter from their address block CCC. Whether truly given assumption?

Experiment with Google IP addresses.

The best confirmation for any theory - practice. We have taken selectively, the casual order, 700 IP addresses belonging Google, after their check its unworked have shown 54 from them. On the rest 646 we measured values Page Rank for our site daily within two months. Page Rank "floated" and changed, sometimes on concrete IP it was updated, sometimes was rolled away back, etc. BUT! With rare exception ABSOLUTELY ALL IPs addresses from one address space of class CCC showed the same values! Our assumption appeared truly!

Let's consider exceptions. Exceptions were that in some address spaces of class CCC, sometimes shown a various values Page Rank, which already next day became again identical to all block CCC. The most interesting will be that such addresses (with not clear behaviour) in our research be only TWO addresses! These are addresses with endings AAA.BBB.CCC.99, AAA.BBB.CCC.104.

What speak about Google datacenters in the internet?

The Internet in general that in itself is an excellent source of the information, after serf on various sites, it was possible collect the following information from different places:

• To Google datacenters different sources during different time carried IP addresses with the following endings: 44, 80, 91, 99, 104, 115, 147, 184, 214
• Till 2004 datacenters Google had own domain names of type: www-XX.google.com, where XX - two symbols from the english alphabet, besides presumably, subsequently these addresses were changed on addresses of type: gfe-XX.google.com (that is understood under GFE - opinions miss, most plausible of met by me - "Google Front End")

Where you datacenters?

What does this information give us? First items of anything! Its statements on the one hand indirectly confirm our researches (99 addresses and 104 there are listed), but other specified addresses did not show strangenesses in behaviour during in our research.

Second items is interesting, it appears that all subdomains gfe-XX.google.com conduct on one and the same IP endings, a brief example:

Really we have found their "residence"? But then where one more IP ending - 99? In fact it too met in our research? What it then a alter-ego of 104 addresses?

Continuation follows...