CONTENTS

 1     Scope          
 2     References
 3     Definitions 
        3.1     Terms defined elsewhere          
        3.2     Terms defined in this Recommendation              
 4     Abbreviations and acronyms              
 5     Feature description 
 6     Capability advertisement      
 7     Call establishment procedure             
        7.1     Gatekeeper parameters            
        7.2     Non-NAT/FW parameters         
        7.3     NAT/FW‑specific parameters   
 8     Calculating media pathways
 9     Determining media strategy
        9.1     Compatibility 
        9.2     Same NAT/FW determination  
        9.3     Must proxy media determination           
        9.4     General NAT strategy determination    
        9.5     Example P2Pnat media calculations      
        9.6     Reporting NAT strategy results to the endpoint
10     Placing the call       
11     Special considerations         
       11.1     RTP/SRTP/RTCP/SRTCP keep-alive packet         
       11.2     Timeouts waiting for first packet          
Annex A – Probing for same NAT    
        A.1     Notification of direct connectivity probing        
        A.2     Procedure to probe direct connectivity
        A.3     Probe packet format