www.googel.com has two IP records. They are on the same IP network. http.www.googel.com and nullmx.www.googel.com are subdomains to this hostname. googel.com is a domain controlled by four nameservers at google.com. All of them are on the same IP network. Incoming mail for googel.com is handled by four mailservers also at google.com. All of them are on different IP networks. googel.com has three IP records. All of them are on different IP networks.