CONTENTS

Introduction    
 1     Scope 
 2     References 
        2.1     IETF
        2.2     ITU-T    
 3     Definitions  
        3.1     General terms        
        3.2     E.164-specific terms          
        3.3     ITU-T non-numbering terms          
        3.4     DNS-specific terms           
        3.5     ENUM-related terms         
 4     Abbreviations   
 5     Background      
        5.1     What is ENUM     
        5.2     DNS zones and delegation 
        5.3     Tiered architecture 
        5.4     Overview of ENUM functions and entities  
 6     General administrative issues and options  
        6.1     Identification of ENUM Tier 1 registry or registries 
        6.2     Delegation of names from the ENUM Tier 1 registry           
        6.3     Determination of ENUM Tier 2 name server provider and ENUM registrars           
        6.4     Validation of ENUM requests and records 
        6.5     Relationships of administrative structures with ENUM zone structures         
        6.6     Additional considerations   
 7     Implications of ENUM for country codes assigned to geographic areas     
        7.1     Administration aspects, options and interfaces        
        7.2     Review of consequences    
 8     Summary and conclusion  
Annex A – Typical PSTN-IP call flows using SIP    
Annex B – Integrated numbering plans