What are Arabic IDNs?
Internationalized Domain Names are domain names represented by Arabic language characters. Such Arabic domain names could contain letters or characters from non-ASCII scripts (for example, Arabic or Chinese). Recently, much effort has gone into making domain names available in character sets other than ASCII, making the Internet more accessible while preserving a naming system that is globally unique and resolvable. Existing Arabic country code domains are going to continue to function as usual with new IDN country codes extensions created. Generic TLDs (.com, etc.) are also planning on implementing new IDN extensions later 2010.
There are two types of IDN domains: partial (IDN.xx) or full (IDN.IDN). A partial IDN has the extension still in Latin-based characters, while full IDNs are completely represented in that language's native character set. IDN.xx domains are already being offered through many gTLD and ccTLD providers [such as 101Домен.com (101domain.com in Russian)] as domains where the native language is displayed for the domain and not the extension. Partial IDN TLDs will lose their effectiveness if the SLD (domain) and the TLD (extension) are in different character sets (such as 101Домен.com) requiring the client to change their keyboard settings to type in the full domain name.
More effective is the full IDN which will have the SLD and TLD in the same character set allowing the client to type the full domain name without the keyboard setting being changed. For example, in Cyrillic, 101domain.rf would be: 101Домен. РФ. While full IDNs can be represented in the native character Unicode, the domain name system only functions with ASCII characters and would not recognize non-English letters and numbers with no accents.
IDN Arabic Challenges
The way around this problem is to encode Unicode characters into Punycode, which is an ASCII representation of the Unicode characters. The marker "xn--" indicates that the domain is an IDN. As far as the DNS itself is concerned, the domain name for 101Домен.com is xn--101-pddf5bif.com.
The biggest technical challenge involves changing all the application software to support IDNs, because IDNs are converted to Punycode in the application and not the DNS system. Internationalized Domain Names were designed to be backwards compatible, as they convert Unicode characters to ASCII characters, so it would not require a wholesale change to the DNS system. They reduced the technical challenge by assigning the support of IDNs from the DNS system level to the application level.
It is up to the application, like the web browser, to convert the Unicode characters into the Punycode representation. There are no changes to the DNS system as the responsibility for encoding IDNs is delegated to the application. The application is what displays the domain as the non-English characters.
Arabic IDN Security
IDNs do not affect DNS security and stability because the DNS only cares about the Punycode version of the domain. IDNs have existed on some extensions since 2002. Though one concern from security experts is the IDN homograph attack, there are characters in other scripts that are identical to characters in ASCII, example LATIN-A (U+0061) and CRYILLIC-A (U+0430) which are different character as far as the computer is concerned, but they look exactly the same on the screen. Web browser developers have responded to this threat by either (in FireFox) only displaying the Punycode version if there is the possibility of the homograph attack, or (in IE & Safari) only displaying domains if they are in one character set. This kind of issue is at the application level, and can be dealt with at that level rather than making changes to the DNS to accommodate for these type of attacks.
Arabic Internationalized Domain Names will increase Internet accessibility worldwide, particularly for people using non-Latin alphabets such as Arabic, Chinese, Cyrillic, Greek, Hebrew, Japanese, and Korean. Many countries have started registrations for IDN.IDN domains. Until these extensions are approved by ICANN and added to the root routers, they cannot be used globally. Pre-orders are already being offered through 101domain.com. Demand is greatest for Arabic, Chinese, Cyrillic, India, and Latin language domains, with more than half of internet users now using non-Latin scripts.