CONTENTS

 1     Scope
 2     Normative references
 3     Definitions
 4     Symbols and abbreviations
 5     Requirements
        5.1     Transport requirements
        5.2     Security considerations
        5.3     Addressing conventions
        5.4     Address templates and descriptors
 6     Message definitions
        6.1     Descriptor
        6.2     Descriptor information
        6.3     Address template
                  6.3.1     Pattern
                  6.3.2     Route information
                  6.3.3     Pricing information
                  6.3.4     Contact information
        6.4     Common structures
                  6.4.1     AlternatePE
                  6.4.2     PartyInformation
                  6.4.3     CallInformation
                  6.4.4     UserInformation
                  6.4.5     Usage specification
                  6.4.6     Security Mode
        6.5     Service relationship
                  6.5.1     Service Request
                  6.5.2     Service Confirmation
                  6.5.3     Service Rejection
                  6.5.4     Service Release
        6.6     Descriptor distribution
                  6.6.1     Descriptor Request
                  6.6.2     Descriptor Confirmation
                  6.6.3     Descriptor Rejection
                  6.6.4     Descriptor ID Request
                  6.6.5     Descriptor ID Confirmation
                  6.6.6     Descriptor ID Rejection
                  6.6.7     Descriptor Update
                  6.6.8     Descriptor Update Acknowledgement
        6.7     Address resolution
                  6.7.1     Access Request
                  6.7.2     Access Confirmation
                  6.7.3     Access Rejection
        6.8     Request in Process
        6.9     Non-standard messages
                  6.9.1     Non-Standard Request
                  6.9.2     Non-Standard Confirmation
                  6.9.3     Non-Standard Rejection
       6.10     Unknown Message Response
       6.11     Usage reports
                 6.11.1     Usage Request
                 6.11.2     Usage Confirmation
                 6.11.3     Usage Rejection
                 6.11.4     Usage Indication
                 6.11.5     Usage Indication Confirmation
                 6.11.6     Usage Indication Rejection
       6.12     Validations
                 6.12.1     Validation Request
                 6.12.2     Validation Confirmation
                 6.12.3     Validation Rejection
       6.13     Authentication
                 6.13.1     Authentication Request
                 6.13.2     Authentication Confirmation
                 6.13.3     Authentication Rejection
Annex A - Message Syntax