Websites on same c class IP address

[seoug_2005]

If two websites are on the same  c class IP address, what does it mean ?

Does two websites belong to the same company ?

[Olaf]

A "C" Block address is based on your IP address.

For example 190.245.111.001 is a standard IP address. The c-blocks in this case are: AAA.BBB.CCC.001-254

So these are within the same C-class:

190.245.111.001
190.245.111.230

And these are different C-Class IP's:

190.245.111.001
190.245.222.001

Google may assume that sites hosted in differnet C-blocks are more likely to be from different people.

[seoug_2005]

Thanks Olaf.

So, does it mean that sites hosted on same C class IP belong to one owner ?

[Olaf]

Not necessarily. f you see different C blocks, you are usually talking about two different webhosts. So there is a chance that different sites from one owner are hosted in one C-block.

Even an IP-address is not always used for one company. You can have your own IP-address which leads to your website. But providers can also share an IP-address for different domains/ websites for different companies.

To find if website belong tot the same owner you need to check te registars database or tools like allwhois.com.

[KeriMorgret]

But if you have 20 sites linking to you, and they're all from the same Class C IP address, and those are pretty much your ONLY links, that looks a bit fishy to the search engines. It's a signal to the search engines that "hey, this person can only get links from sites that have a high probability of the same person being in control of all of the sites".

That's why you'll see people talk about linkbuilding and wanting to do so from different Class C IP addresses.