Consider name length and complexity. First, choose names that are descriptive. For example, "Sales" is considerably more descriptive than "BW23A." Second, choose short names. To make your administrative work easier, avoid long names such as administration_services.corporate_headquarters.doc.com.
A domain name is formed from left to right, starting with the local domain and ending with the root domain. The root domain must always have at least two labels and must end in a dot. The second label can be an Internet domain name, such as "com."
Depending on the migration strategy, a viable alternative is to change domain names on NIS to the desired structure, then migrate to NIS+ domain by domain.