Hyperlink Graph of the World Wide Web of 2012 (aggregated by first level subdomains)

Knowledge about the general graph structure of the hyperlink graph is important for
designing ranking methods for search engines. To amend the ranking calculated by search
engines for different websites, search engine optimization agencies focus on linkage
structure for their clients. An extreme appearance of ranking manipulation manifests in
spam networks, where pages and websites publishing dubious content try to increase their
ratings by setting a massive number of links to other pages and retrieve backlinks. The
WDC Hyperlink Graph on first level subdomain level has been extracted from the Common
Crawl 2012 web corpus and covers 95 million first level subdomains, linked by almost 2
billion connections, which are derived from the hyperlinks of the pages contained by the
first level subdomains.