CONTENTS

 1     Scope 
 2     References 
        2.1     Normative references         
      2.2  Informative references and bibliography          
 3
     Terms and Definitions      
 4     Abbreviations   
 5     Conventions     
        5.1     Recommendation version   
 6     Definition of the VBD mode of operation  
        6.1     Minimum requirements for VBD mode of operation
 7     Negotiation of support of VBD and selection of VBD codec and other VBD enhanced functionality    
        7.1     Negotiation using Session Description Protocol (SDP)        
        7.2     Use of VBD in H.323 systems       
 8     The use of RFC 2833 modem/facsimile/text telephone events       
 9     VBD stimuli      
10     Procedures for transitioning between audio mode and VBD mode           
11     Optional procedures for indicating to a remote end transition into VBD using State Signalling Events (SSEs)    
       11.1     Declaration of SSEs          
       11.2     Transition to the VBD mode for V.150.1 gateways           
       11.3     Transition to the VBD mode for non-V.150 cases 
       11.4     Transition from the VBD media mode       
       11.5     Security – Optional           
Annex A – Vendor-defined messages