You must be a structure related to the higher education ministry in Tunisia. Documentation showing you are an educational institution of Tunisia. The entity should have the approval of the head of the institution.

Individual registrations not allowed. ONLY companies and legal entities can register this

The minimum term for .rnu.tn domain names is 1 year

The domain registration time frame for .rnu.tn during general availability is 1 Week.

Domain Names must:

• have minimum of 3 and a maximum of 63 characters;
• begin with a letter or a number and end with a letter or a number;
• use the English character set and may contain letters (i.e., a-z, A-Z),numbers (i.e. 0-9) and dashes (-) or a combination of these;
• neither begin with, nor end with a dash;
• not contain a dash in the third and fourth positions (e.g. www.ab- -cd.rnu.tn); and
• not include a space (e.g. www.ab cd.rnu.tn).

You may visit them here: Agence tunisienne d'Internet.