This Recommendation contains terms and definitions and a framework relevant to providing a general understanding of next generation networks and a guide for the development of NGN documents in the ITU.

This Recommendation is not simply a compendium of terms and definitions. The primary purpose of this Recommendation is to provide a context for the use of certain terms and definitions to avoid misunderstandings in NGN activities. Thus, the definitions are arranged in a specific order and certain necessary relationships are illustrated. Additionally, explanatory notes are also included where deemed appropriate.

This Recommendation uses terms and definitions, which are considered particularly suitable and applicable to NGN work and that have already been defined in published ITU-T Recommendations. Additionally, where new terms were required they have been defined in this Recommendation.