Table of Contents

 1     Scope          
 2     Introduction             
 3     References
 4     Abbreviations and acronyms
 5     Terms and definitions            
 6     Network configurations for using IP telephony            
        6.1     Configuration A: Phone-to-phone communication (with IP transit network)          
        6.2     Configuration B-1: IP phone-to-phone communication  
        6.3     Configuration B-2: Phone-to-IP phone communication  
        6.4     Configuration C: IP phone-to-IP phone communication 
 7     Network capabilities to support IP telephony
        7.1     Service aspects             
        7.2     Charging considerations           
        7.3     Quality of service (QoS) considerations
        7.4     User identification and addressing considerations           
        7.5     Security considerations             
 8     Network capabilities to support IP telephony interworking between the PSTN and the IP network    
 9     Network address translation (NAT) and firewalls         
10     Control protocols for support of IP telephony            
Appendix I – Supplementary services and the corresponding ITU-T Recommendations that define them    
Appendix II – Standard development related to IP telephony    
Appendix III – J-series ITU-T Recommendations in support of IP telephony