Make an anonymous network of web sites (MFA, ...) with the IP Failover

Following a site Discodog article entitled "10 golden rules for creating an MFA" I decided to present a technique to try to make an anonymous network of sites (not necessarily of the MFA!).
It is common to hear about the SEO forums that it makes sense to have sites hosted on different IP to mask its network of sites. Indeed, because the greater your websites more tempted to make them backlinks and great (especially if they have the same theme).
Why not host my website on the same IP?

It is recommended not to host sites on the same IP for two reasons:
- Firstly, there are Internet tools to do reverse IP lookup, ie they can list all domain names hosted on the same IP (I will return one of these tools in a next section). So even if you have not linked your sites between them, your network is easy to detect!
- Moreover, if you make between your sites backlinks, some believe that Google Referrals (and other search engines) may penalize you if they are hosted on a Class C IP identical (note that this is an affirmation to take with tweezers!).
What is a Class C IP?

Say you have a Site that for IP 85.90.95.100 and a site B's IP 85.90.95.101 and many people will say that sites A and B have the same C class (in this case 85.90.95).
If Site B had the IP 85.90.96.101, Class C of the two sites is different (85.90.95 to 85.90.96 and site A for site B).

How to host my websites on Class C IP different?

Let's review the possible solutions:
- A shared hosting different for each site: this method quickly finds its limit as a host can not guarantee that each site will be hosted on a different IP (and even less on a Class C IP different) so you can have at least 2 sites that you belong among the hundred site hosted on the server.
- A private server (RPS style at OVH) / dedicated by different website: it approaches the solution, however, a solution is expensive (12 € per month minimum for the RPS to a score of at least EUR for a dedicated server) for the mere purpose of having a different IP. Also, if you are familiar with the fact that there will be a different IP, you can not be sure of a Class C IP different.
The solution: a dedicated server with failover ip

It is a solution I found in the host OVH. Simply put, this involves renting a dedicated server on which you will be able to transplant 30 different ip above (price 1 € per IP at OVH). Moreover, not only can you choose a geographic IP (Germany, England, France, ...) depending on the target of your websites but it is also possible and is the major asset, choosing Class C IP different.
Conclusion

With the solution of the IP failover, you will be able to hide your network site to the tool such that the reverse ip lookup (it will be only one domain hosted on IP) or to for the search engines. However, this technical solution has its limits. In fact, here are some cases where the advantage of IP Failover become zero:
- If you use Google Adsense or Google Analytics on all your sites. It is very easy for Google to make the connection between all sites including your login. I suggest you take a look at Piwik, a free alternative to Google Analytics.
- If the whois of your domain name is not anonymous. Remember that whois is searchable by anyone! Some hosts offer to make the anonymous whois.

What do you think of this solution? Did you know her?