ns1.isu.net.sa has one IP number , which also has a corresponding reverse pointer. sa, com.sa, net.sa, sch.sa, pub.sa and at least 61 other hosts use this as a nameserver. isu.net.sa is a domain controlled by two nameservers at isu.net.sa themselves. They are on the same IP network. Incoming mail for isu.net.sa is handled by two mailservers also at isu.net.sa. They are on the same IP network. isu.net.sa has one IP number. ns1.isu.net.sa is hosted on a server in Saudi Arabia.