cursos.itesm.mx has two IP numbers. They are on the same IP network. This hostname cnames to cursos.itesm.mx.edgesuite.net. jobs.com, 72.ufc.com, im.sify.com, aka.p80.net, www.aeat.es and at least 100 other hosts point to the same IP. itesm.mx is a domain controlled by three nameservers at itesm.mx themselves. All of them are on different IP networks. Incoming mail for itesm.mx is handled by nine mailservers also at itesm.mx. Some of them are on the same IP network. itesm.mx has three IP numbers. All of them are on the same IP network. cursos.itesm.mx is hosted on two servers in United States even though the hostname implies Mexico.