Recommendation ITU-T G.709.1/Y.1331.1 (2018) Amd.4 (08/2023) Flexible OTN short-reach interfaces
Summary
History
FOREWORD
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 Introduction and applications
     6.1 FlexO-x-RS-m interface group considerations
7 Structure and processes
     7.1 Basic signal structure
     7.2 Processing and information flow
8 FlexO frame
     8.1 Frame structure
     8.2 Multi-frame structure
     8.3 Bit rates and frame periods
     8.4 FlexO-xO-x(e) frame structure
9 Alignment mechanism field markers and overhead
     9.1 Lane alignment markers
          9.1.1 FlexO-1 alignment markers
          9.1.2 100G FlexO PAD
          9.1.3 FlexO-2 alignment markers
          9.1.4 FlexO-2 PAD
          9.1.5 FlexO-4 alignment markers
          9.1.6 FlexO-4 PAD
     9.2 Basic overhead (BOH) description
          9.2.1 Multi-frame alignment signal (MFAS)
          9.2.2 Group management overhead
               9.2.2.1 Group identification (GID)
               9.2.2.2 FlexO instance identification (IID)
               9.2.2.3 FlexO map (MAP)
          9.2.3  Clause intentionally left blank
          9.2.4 Clause intentionally left blank
          9.2.5 Status (STAT)
               9.2.5.1 Remote PHY fault (RPF)
               9.2.5.2 Reserved (RES)
               9.2.5.3 Maintenance (MNT)
          9.2.6 Payload overhead
               9.2.6.1 OTUC availability (AVAIL)
               9.2.6.2 Payload type (PT)
               9.2.6.3 Client specific overhead allocation
          9.2.7 Cyclic redundancy check (CRC)
          9.2.8 FlexO management communications channel (FCC1)
          9.2.9 FlexO reserved overhead (RES)
          9.2.10 OTN synchronization message channel (OSMC)
               9.2.10.1 Generation of event message timestamp
     9.3 Extended overhead (EOH) description
          9.3.1 FlexOfec overhead
               9.3.1.1 Staircase FEC block alignment (FBA) field
          9.3.2 FlexOsec overhead
               9.3.2.1 Authentication tag (AT)
               9.3.2.2 Frame number (FN)
               9.3.2.3 Key index (KI)
               9.3.2.4 Cipher suite type (CST)
               9.3.2.5 Key exchange communication channel (KCC)
               9.3.2.6 Reserved (RES)
          9.3.3 FlexO regen overhead
               9.3.3.1 Regen multi-frame alignment signal (RMFAS)
               9.3.3.2 Regen status (RSTAT)
                    9.3.3.2.1 Remote fault indication (RF)
                    9.3.3.2.2 Degrade indication (LD/RD)
                    9.3.3.2.3 Reserved (RES)
               9.3.3.3 Regen trail trace identifier (RTTI)
               9.3.3.4 FlexO regen communication channel (FCC0)
     9.4 Frame alignment (FA)
10 FlexO Mapping mapping of OTUCn signal into n FlexO instancesprocedures
     10.1 BMP mapping of OTUCn client into FlexO-x
          10.1.1 Distributing OTUCn and combining OTUC instances
          10.1.2 FlexO multi-frame payload
          10.1.3 Mapping of OTUC into FlexO multi-frame payload
               10.1.3.1 Mapping of OTUC into FlexO frame
          10.41.4 FlexO-x--m group alignment and deskewing
          10.1.5 Client mapping specific overhead
     10.2 GMP mapping of Ethernet client into FlexO-xe
          10.2.1 FlexO frame and 4-frame multi-frame payload structure
          10.2.2 Ethernet characteristic information
          10.2.3 Client mapping specific overhead
               10.2.3.1 FlexO multiplex structure identifier (MSI)
               10.2.3.2 FlexO justification overhead (JC)
               10.2.3.3 Client status (CSTAT)
                    10.2.3.3.1 Client signal fail (CSF)
                    10.2.3.3.2 Reserved (RES)
                    10.2.3.3.3 Maintenance (MNT)
                    10.2.3.3.4 Client degrade indication (LD/RD)
     10.3 FlexO payload PRBS test pattern
          10.3.1 Client mapping specific overhead
11 100G FlexO-1-RS interface
     11.1 Frame structure
     11.2 Bit rate and frame periods
     11.3 Overhead
     11.4 Scrambling
     11.5 Forward error correction (FEC)
     11.6 FOIC1.k-RS interface
          11.6.1 FOIC1.4-RS interface
          11.6.2 FOIC1.4-RS skew tolerance requirements
          11.6.3 FOIC1.4-RS 28G lane bit rate
          11.6.4 m*FOIC1.4-RS interface
          11.6.5 FOIC1.1-RS interface
          11.6.6 FOIC1.1-RS skew tolerance requirements
          11.6.7 FOIC1.1-RS 112G lane bit rate
12 200G FlexO-2-RS interface
     12.1 Frame structure
     12.2 Bit rate and frame period
     12.3 Overhead
     12.4 Scrambling
     12.5 Forward error correction (FEC)
     12.6 FOIC2.k-RS interface
          12.6.1 FOIC2.4-RS interface
          12.6.2 FOIC2.4-RS skew tolerance requirements
          12.6.3 FOIC2.4-RS 56G lane bit rate
          12.6.4 m*FOIC2.4-RS interface
          12.6.5 FOIC2.4-RS interface processes
13 400G FlexO-4-RS interface
     13.1 Frame structure
     13.2 Bit rate and frame periods
     13.3 Overhead
     13.4 Scrambling
     13.5 Forward error correction (FEC)
     13.6 FOIC4.k-RS interface
          13.6.1 FOIC4.8-RS interface
          13.6.2 FOIC4.8-RS skew tolerance requirements
          13.6.3 FOIC4.8-RS 56G lane bit rate
          13.6.4 m*FOIC4.8-RS interface
          13.6.5 FOIC4.8-RS interface processes
          13.6.6 FOIC4.4-RS interface
          13.6.7 FOIC4.4-RS skew tolerance requirements
          13.6.8 FOIC4.4-RS 112G lane bit rate
Annex A  Forward error correction for FlexO-x-RS (x = 2,4) using 10-bit  interleaved RS(544,514) codecs
Annex B  FlexOsec encryption and authentication
     B.1 GCM-AES-256 frame payload encryption
          B.1.1 GCM-AES-256 confidentiality (encryption)
          B.1.2 GCM-AES-256 integrity (authentication)
          B.1.3 IV construction
          B.1.4 GCM-AES-256 algorithms
Annex C  GMP parameters for mapping Ethernet to FlexO-xe
Appendix I  Example applications
Bibliography