User manual

Appendix D
164
To edit another domain, select another domain from the Select Domain
or Network... pull-down menu. You can select any domain that you
have configured for the DNS server.
To add a new domain, use the Add... pull-down menu again. In the
Domain Name field, replace the default domain name with the new
domain name that you want to create.
For further information, refer to the following:
• In the Cobalt Knowledge Base, search on “DNS”.
• http://www.dnswiz.com/dnsworks.htm
• http://www-europe.cisco.com/warp/public/787/indexDNS.html
Brief history of the Domain Name System (DNS)
In the 1960s, the U.S. Department of Defense Advanced Research
Projects Agency (ARPA, and later DARPA) began funding an
experimental wide area computer network called the ARPAnet. The
ARPAnet used a centrally administered file called HOSTS.TXT which
held all name-to-address mapping for each host computer connected to
the ARPAnet. Since there were only a handful of host computers at the
start, HOSTS.TXT worked well.
When the ARPAnet moved to the Transmission Control Protocol/
Internet Protocol (TCP/IP) suite of protocols and become known as the
Internet, the population of the network exploded. HOSTS.TXT became
plagued with problems, namely
• traffic and load
• name collisions
• consistency
A replacement for the HOSTS.TXT file was needed. The goal was to
create a system that solved the problems inherent in a unified host table
system. The new system should allow local administration of data and
also make that data globally available.
In 1984, the architecture of a new system called Domain Name System
(DNS) was designed and is the basis of the DNS service used today on
the Internet.