My 9/20/09 Missoulian column
The emergence of the Domain Name System is yet another important part of the history of the Internet. DNS is one of the modern “glues” that holds the Internet together. Think of trying to find a business phone number without a phone book, or a street address without a map and street index. Not very easy, right?
DNS provides a central “phone book” for billions of Web sites, and every new domain that appears (what goes before the .com, .net or .org in a Web site) gets “listed” in the the main DNS phone book within a day.
The DNS system also does on-the-fly translations of difficult to remember numerical Web site addresses – such as 126.96.36.199 – into easy to remember Web sites, such as SongdogTech.net.
Early on, a standardized DNS-like system didn’t exist. For instance, on early networks (like ARPANET in the 1970s) each had to exchange their own “maps” of networks so computers could find each other.
Early network engineers recognized that a standardized system was needed, but that system also needed to be decentralized in order to be reliable and serve all Internet users, equally.
The result was DNS, invented in 1983. The next year, students at Berkeley wrote Berkeley Internet Name Domain, the first version of today’s DNS software.
The modern DNS system uses what are called “root” servers, thirteen fast computers with extensive security and power backup systems. They trade DNS updates among themselves – whenever someone registers or drops a domain – and pass those changes along to other DNS servers in a trickle down manner.
That’s the reason why you can register a Web site domain and it will be available very quickly. A modern and very busy DNS system has its share of problems, though.
These include domain disputes, which are handled by the Internet Corp. on Assigned Names and Numbers, a private corporation that deals with domain allocation and administration.
And the BIND software has security problems. Last August, I covered the story of a vulnerability discovered that allowed “poisoning” and corruption of DNS records, resulting in the possibility of fake Internet phone book records fooling users.
BIND was originally conceived as a system that depended on trust, and there are new efforts to encrypt DNS traffic and bring it up to speed for security conscious modern times.