Back in the mid-1990s, when awareness of the Internet and the World-Wide Web was just beginning to grow in the general population, I was asked several times some variant of the question, “Why do all the Internet site names end in
.com?”. I would then explain that, actually, they didn’t; although most of the sites that were advertised ended in
.com, there were other “endings”, as exemplified by
mit.edu. If the person’s eyes had not already glazed over, I would try to explain that the names were part of the Domain Name Service [DNS], which translated names into the actual numeric Internet addresses, and that the names were assigned in a tree structure, in which the name became more specific as one read right to left. (Computer scientists are a funny bunch; in addition to reading backwards, they always start counting “0, 1, 2 …”.) In the initial system, there were eight top-level domains [TLDs]:
.com, .edu, .org, .mil, .gov, .net, .arpa, .int
plus a parallel system of two-letter country TLDs:
.ca for Canada,
.jp for Japan,
.us for the United States, and everyone’s favorite misleading entry,
.ch for Switzerland. (The code for China is
.cn.) The idea behind this system is that the management of sub-domains can be delegated. Once Princeton University is assigned the domain
princeton.edu, for example, it can then set up sub-domains within it, such as
The governing organization responsible for managing DNS names, the Internet Corporation for Assigned Names and Numbers [ICANN], has made some additions over time, introducing such new TLDs as
.biz, and, most controversially,
.xxx (for porn sites). Earlier this week, ICANN announced a new policy for global TLDs, so-called “generic” names, which would make possible TLDs like
“ICANN has opened the Internet’s naming system to unleash the global human imagination. Today’s decision respects the rights of groups to create new Top Level Domains in any language or script. We hope this allows the domain name system to better serve all of mankind,” said Rod Beckstrom, President and Chief Executive Officer of ICANN.
ICANN also adopted guidelines to ensure that, for example, Microsoft cannot register a
.apple TLD. The initial round of registrations will begin in January, 2012, and new TLDs will be limited to 1,000 per year. The application fee is $185,000 (so don’t expect
.rich anytime soon).
It seems like an appropriate day for writing about this; as an article at Wired reminds us, it was on this date, back in 1983, that Paul Mockapetris and Jon Postel ran the first successful test of the Domain Name System.