Unicode Domain Implementation Guide

This guide explores technical implementation details of Unicode in domain names.

Unicode Normalization

Before using Unicode characters in domain names, they must undergo Unicode normalization to ensure consistent representation. 


Example before normalization:
ελβββββοα → ελβββββοα

After Unicode normalization:
ελβββββοα → βββββοα (with appropriate code points)

Normalization Forms

  • Normalization Form C (NFC) - Composed characters
  • Normalization Form D (NFD) - Decomposed characters
  • NFKC and NFKD - Special-case normalization

Security Implications

  • Homoglyph detection for security
  • Confusable characters validation
  • Unicode security policies implementation

Implementation Best Practices

Validation Techniques

Use ICU library for proper Unicode handling in applications.

Testing Requirements

Test with IDN testing tools like iana.org/idn.

Implementation

Integrate with IDNA2008 compliant libraries.