6.4.3. Assignment

This section describes how URNs are assigned within the namespace. It needs to explain:

1. Assignment authority: Who is responsible for assigning URNs
2. Assignment process: How to apply for and obtain a URN
3. Assignment policy: Centralized or distributed assignment
4. Uniqueness guarantee: How to ensure each URN is assigned only once
5. Persistence commitment: How to guarantee long-term validity of URNs

The assignment process should be clear, executable, and ensure uniqueness and persistence of URNs.