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            
        5.1     Notational     
        5.2     Diagrammatic               
        5.3     Terminological             
        5.4     Representational       
 6     Functional architecture of OTN        
 7     OTN digital layers   
        7.1     Optical data unit (ODU) layer network              
        7.2     Optical transport unit (OTU) layer network     
        7.3     Client/server associations       
 8     Architecture of the media layer       
        8.1     Media constructs        
        8.2     Media element           
        8.3     Optical tributary signals and interfaces             
        8.4     Management of optical signals             
        8.5     Management of media and signals      
        8.6     Modulator and termination functions
        8.7     Client/server associations       
 9     Media topology      
        9.1     Unidirectional and bidirectional connections  
        9.2     Point‑to‑multipoint media channels   
10     Management         
       10.1     Requirements            
       10.2     Connection supervision techniques  
       10.3     Connection or media channel supervision applications             
11     OTN survivability techniques           
12     The black link approach     
Annex A – Media change and physical domain change    
Appendix I – Relationship between OCh and OTSi terminology    
Appendix II – Use of the OTN to carry Flex Ethernet    
       II.1     Overview of Flex Ethernet       
       II.2     FlexE unaware              
       II.3     FlexE aware   
       II.4     FlexE terminating        
Appendix III – Examples of views of an ODU layer network    
Appendix IV – Examples of multi‑domain OTN applications    
Appendix V – Examples of the configuration of media channels    
        V.1     Construction of network media channels         
        V.2     Use of flexible grid capable filter to route media channels        
Appendix VI – Example of media network using tuneable modulator/demodulator for routing    
       VI.1     Network using couplers           
       VI.2     Network using wide-band filters and couplers