What is an Internationalized Domain Name (IDN)?
IDNs enable people around the world to use domain names in local languages and scripts. They are domain names that contain characters outside of American Standard Code for Information Interchange (ASCII). In other words, IDNs are domain names that include something other than the letters of the basic Latin alphabet (a-z), numerical digits (0-9), and a hyphen (-), which are applicable to web users whose language uses a different script (such as Arabic) or contains words that use diacritics (such as French accented letters). IDNs are the mechanism that allows the Domain Name System (DNS) to recognize when web users enter domain names that contain these characters.
There are two ways to represent an IDN. The U-label is the Unicode form of an IDN. It is how the domain appears to the end user in the web address bar, in its original script or with the correct accented characters. For example, façon.ca.
The second way, the A-label, is the ASCII representation of an IDN without any accented characters – it only contains letters from the basic Latin alphabet (a-z), digits (0-9), and a hyphen (-). To represent an IDN as an A-label, the U-label is converted using something called Punycode. Using Punycode, non-ASCII characters are converted into a format which uses only ASCII characters. This allows a unique and reversible identification of the original domain.
When using façon.ca, it would be converted to the A-label and be represented as xn--faon-1oa.ca.
More information on IDNs can be found on ICANN’s website.
How does .CA manage IDNs?
In 2012, CIRA introduced support for the full range of French characters in .CA domain names: é, ë, ê, è, â, à, æ, ô, œ, ù, û, ü, ç, î, ï, ÿ. When a .CA is registered, all variations of a domain name with these accented characters (what we call the “administrative bundle”) are reserved for the registrant and cannot be registered by anyone else.
Although these domain names are reserved for the registrant, they are not active – that is they do not automatically resolve. The registrant must register them with a registrar that offers this service. Each domain name you wish to use must be registered individually, with the same registrar. Each of these registered names will have its own lifecycle.
To use an example, there are 18 variants in the administrative bundle for www.cira.ca: