Internationalized Domain Name – Software Development Kit

The Internationalized Domain Name – Software Development Kit (IDN SDK) supports domain registrars in the process of normalizing and encoding data for domain name system registration. The library provides tools for any client or server applications that may need to convert from one encoding to another.

IDN Standards

The Verisign implementation of IDN registration for the .com, .net, .cc, .name, .닷컴, .コム, .닷넷, and קום. top-level domains follows the specification set forth by the Internet Engineering Task Force in these RFC documents:

• RFC 3492 - Processes for Punycode
• RFC 5891 – IDNA Protocol
• RFC 5892 – IDNA Unicode
• RFC 5893 – IDNA Right-to-Left Scripts
• RFC 5894 – Rationale
• RFC 5895 – Character Mapping

Documentation

Verisign's IDN SDK includes:

• User’s Guide: A high-level look at the contents of the library and an overview of the problems that it can solve.
• Programmer’s Guide: Contains instructions for users who will incorporate or extend the software provided in the library.
• Registrar’s Guide: Gives instructions on how to create Punycode domains and also provides some help in troubleshooting common errors during registration.

The library is delivered in the ZIP file format. The data inside is compressed and archived. Most operating systems can natively decompress this format. Various third-party tools are also available.

The single IDN SDK package (~5 MB) contains all software, including an API, tools, and tests for both C and Java languages.

Additional IDN Libraries

Libraries that implement the Internationalizing Domain Names in Applications (IDNA) standard for a variety of programming environments are available in the public domain. Verisign encourages and supports the work of such developers and provides links to these libraries. Application developers should choose the library that best fits their application requirements.