In the spring of 1991, Prime Suspect and Mendax began a race to get root on the US Department of Defense's Network Information Center (NIC) computer--potentially the most important computer on the Internet. As both hackers chatted amiably on-line one night, on a Melbourne University computer, Prime Suspect worked quietly in another screen to penetrate ns.nic.ddn.mil, a US Department of Defense system closely linked to NIC. He believed the sister system and NIC might `trust' each other--a trust he could exploit to get into NIC. And NIC did everything. NIC assigned domain names--the `.com' or `.net' at the end of an email address--for the entire Internet. NIC also controlled the US military's own internal defence data network, known as MILNET. NIC also published the communication protocol standards for all of the Internet. Called RFCs (Request for Comments), these technical specifications allowed one computer on the Internet to talk to another. The Defense Data Network Security Bulletins, the US Department of Defense's equivalent of CERT advisories, came from the NIC machine. Perhaps most importantly, NIC controlled the reverse look-up service on the Internet. Whenever someone connects to another site across the Internet, he or she typically types in the site name--say, ariel.unimelb.edu.au at the University of Melbourne. The computer then translates the alphabetical name into a numerical address--the IP address--in this case 128.250.20.3. All the computers on the Internet need this IP address to relay the packets of data onto the final destination computer. NIC decided how Internet computers would translate the alphabetical name into an IP address, and vice versa. If you controlled NIC, you had phenomenal power on the Internet. You could, for example, simply make Australia disappear. Or you could turn it into Brazil. By pointing all Internet addresses ending in `.au'--the designation for sites in Australia--to Brazil, you could cut Australia's part of the Internet off from the rest of the world and send all Australian Internet traffic to Brazil. In fact, by changing the delegation of all the domain names, you could virtually stop the flow of information between all the countries on the Internet. The only way someone could circumvent this power was by typing in the full numerical IP address instead of a proper alphabetical address. But few people knew the up-to-twelve-digit IP equivalent of their alphabetical addresses, and fewer still actually used them. Controlling NIC offered other benefits as well. Control NIC, and you owned a virtual pass-key into any computer on the Internet which `trusted' another. And most machines trust at least one other system.