Glossary/C-block
Revision as of 21:53, 25 April 2011 by KristinaWeis (talk | contribs) (per thomas)
176.185. Each website on the Web is actually an IP address and the domain name (like example.com) takes us to that IP address.
One spammy, black hat SEO tactic that some people have used is buying many domain names and making websites that all link to a different website that they're trying to boost the SEO and rankings of. When buying domain names in bulk, it's easiest to just buy an entire block of IP address -- a C-block. Hosting providers also buy large blocks of IPs, so if you have a lot of websites hosted by the same provider they may be in the same c-block.
Search engines have caught on to this tactic and they're leary of websites that have tons of inbound links from websites all in the same C-block of IP addresses. However, since we have run out of IPv4 addresses, websites ending up in the same c-block will become more and more common, and should be less of an SEO issue in the future.