Table of Contents

 1     Scope          
 2     References
 3     Definitions 
        3.1     Terms defined elsewhere        
        3.2     Terms defined in this Recommendation            
 4     Abbreviations and acronyms             
 5     Conventions             
 6     Packet network architectures           
        6.1     Network layers and synchronization   
        6.2     Layer network performance impacts on synchronization           
 7     Timing flows             
 8     Functional blocks    
 9     Next generation timing architectures            
        9.1     Current synchronization based on SDH              
        9.2     Synchronization performance
        9.3     Network evolution      
        9.4     Next generation synchronization networks     
10     Frequency transfer using synchronous Ethernet     
       10.1     Synchronous Ethernet: General           
       10.2     Operation modes       
11     SSM for synchronous Ethernet       
       11.1     Packet-level SSM        
       11.2     Sync selection based on SSM
       11.3     SSM for synchronous Ethernet: Format and protocol 
       11.4     ESMC PDU extensions              
       11.5     Interworking with existing synchronization networks
       11.6     SSM for clocks with enhanced holdover           
12     Use of synchronous Ethernet in a multi-operator context  
       12.1     Timing transparent transport of synchronous Ethernet client signals   
       12.2     Synchronization service provided by the carrier operator based on an interface providing a physical timing reference (generation of synchronous Ethernet interface)    
13     Synchronization management aspects        
Annex A – Reference source selection mechanism    
        A.1     Requirements              
        A.2     Inputs              
        A.3     Internal oscillator        
        A.4     Internal physical timing flows – Frequency ETY              
        A.5     Selection mechanism
        A.6     Synchronization status message selection       
        A.7     Hybrid equipment selection function 
Appendix I – Examples of timing flows    
Appendix II – Functional models based on ITU-T G.805 and ITU-T G.809    
       II.1     Background     
       II.2     Application of ITU-T G.805 to the IWF  
       II.3     Timing information transported over layer networks   
       II.4     Functional model of Ethernet physical layer timing        
       II.5     Functional model for differential and adaptive methods            
Bibliography