How does Alexa do that?

Jay Daley · May 19, 2006

Can anyone explain how Alexa joins up ownership of domains? For example, when you look up nominet.org.uk then it can tell that we have nominet.org but don't have nominet.com. Is it just matching by registrant name and storing WHOIS data?

If so, then how does it avoid common registrant names such as Mr Smith.

Jeewhizz · May 19, 2006

I think they store the IP and check what others ones do it, as they'll match domains on a shared host

texidriver · May 20, 2006

Jay Daley said:
it can tell that we have nominet.org but don't have nominet.com.

Unique Visitors per month*: 3,203

Why don't you just DRS them and show us how it is done?

Jay Daley · May 20, 2006

Jeewhizz said:
I think they store the IP and check what others ones do it, as they'll match domains on a shared host

Thanks but I didn't actually understand that. Can you try again?

olebean · May 20, 2006

Jay

Why would Nominet want to know? Do you think they might be using whois and storing the data?

Jay Daley · May 20, 2006

texidriver said:
Jay Daley said:

it can tell that we have nominet.org but don't have nominet.com.

Unique Visitors per month*: 3,203

Why don't you just DRS them and show us how it is done?

Click to expand...

Erm, do you mean UDRP? Bit worrying to think that even seasoned professionals get confused by all of this.

Jay Daley · May 20, 2006

olebean said:
Jay

Why would Nominet want to know? Do you think they might be using whois and storing the data?

If I knew what they did then I might start to get anxious. For the moment though I'm just investigating.

Jeewhizz · May 20, 2006

OK, From the way I understand it, this is how its done:

mydomain.com points to 1.2.4.5
myotherdomain.com also points to 1.2.4.5

and thus they 'relate them' together.

Bit pointless, as they also don't account for shared hosting servers that can have 1000's, and also load balancers...

whois.sc.do something similar as well

retired_member6 · May 20, 2006

Well they appear to nick/buy/borrow whois contact details off of .com. I certainly never gave alexa permission to display my contact details on their website. Complaint on way.

Edited site info, no need for complaint, cheeky 'kers.

retired member 1 · May 21, 2006

Whoops......

netserve · May 21, 2006

I've just checked a .com which has a name in the whois but no valid address.
The .com doesn't show any associated domains.

The matching .co.uk hosted on the same server shows associated domains, all .co.uk. Whats interesting is that the address is visible in the whois for the .uk domains. They're all hosted on different networks, so different IP's. ie the only way to associate them is via the address on the Nominet whois.

From what I can see there are other .uk domains with the same owners name, but no public whois address that aren't associated by alexa.

So yes, from what I can see, alexa is linking domains based on the name and address from the .uk whois.

aquanuke · May 21, 2006

Dosent Google also scan the UK whois and compile information about which sites are owned by the same folks.

Wouldnt that also be against Nominets T&C ?

olebean · May 21, 2006

A while back I checked one of my domains with Alexa incorrect contact details were published...

Jay Daley · May 21, 2006

netserve said:
So yes, from what I can see, alexa is linking domains based on the name and address from the .uk whois.

Thank you. We will probably take this further.

Jay Daley · May 21, 2006

aquanuke said:
Dosent Google also scan the UK whois and compile information about which sites are owned by the same folks.

Do you have a link to where they do show the results of this? Or is it just built into PageRank?

Whois-Search · May 22, 2006

invincible is right.

On whois-search.com and deleting.co.uk they are listing milly.co.uk which I don't even host but own.

http://www.alexa.com/data/details/main?q=whois-search.com&url=whois-search.com

http://www.alexa.com/data/details/main?q=domain-shop.co.uk&url=deleting.co.uk

On domain-shop.co.uk they are showing my email address which is not on Nominet whois.

http://www.alexa.com/data/details/main?q=domain-shop.co.uk&url=domain-shop.co.uk

Whois-Search · May 22, 2006

whois.sc do have the reverse-ip tool :

http://www.domaintools.com/reverse-ip/

You can find their patent application on:

http://appft1.uspto.gov/netahtml/PTO/search-bool.html

By searching for "reverse ip":

20060031385 Reverse IP method and system