00 0 THE TELECOMMUNICATION TECHNOLOGY COMMITTEE

... 5... 5... 6 G.709... 6... 7 ITU-TG.709... 8... 8... 8... 8... 5... 5 6... 5 6... 5 6..OC... 6 6..OTM-n.m(n)... 6 6..OTM-nr.m OTM-0.m... 6 6.OTN... 7 7./... 0 7... 0 7... 7... 8.(OTM-n.m,OTM-nr.m,OTM-0.m)... 8.OTM(OTM-0.m,OTM-nr.m)... 8..OTM-0.m... 8..OTM-6r.m... 8.OTM(OTM-n.m)... 6 9.ONNI... 8 9.OTM-0.m... 8 9.OTM-6r.m... 8 9.OTM-n.m... 8 0.(OCh)... 8 0.OCh(OCh)... 8 0. OCh(OChr)... 9.(OTU)... 9.OTUk... 9....(ODUk)....ODUk....(OPUk)....OTM (OOS)... 5...

5... 5..OPUk OH... 5..ODUk OH... 5..OTUk OH... 5..Och OH... 5..5OMS OH... 5..6OTS OH... 5..7COMMS OH... 5... 7 5.OTS OH... 9 5..OTS TTI... 9 5..OTS BDI-P... 9 5..OTS BDI-O... 9 5..OTS PMI... 0 5.OMS OH... 0 5..OMS FDI-P... 0 5..OMS FDI-O... 0 5..OMS BDI-P... 0 5..OMS BDI-O... 0 5..5OMS PMI... 0 5.5Och OH... 0 5.5.Och FDI-P... 0 5.5.Och FDI-O... 5.5.Och OCI... 5.6OTUk/ODUk... 5.6.OTUk/ODUk... 5.6.OTUk/ODUk... 5.7 OTUk... 5.7.OTUk... 5.7.OTUk... 5.7.OTUkV... 6 5.8 ODUk... 7 5.8.ODUk... 7 5.8.ODUk... 8 5.9OPUk... 6 5.9.OPUk... 6 5.9.OPUk... 6 5.9.. OPUk (PSI)... 6 6... 6 6.OTS... 6 6.OMS... 6 6..OMS -(OMS-FDI-P)... 65 6..OMS -(OMS-FDI-O)... 65

6..OMS (OMS-PMI)... 65 6.OCh... 65 6..OCh -(OCh-FDI-P)... 65 6..OCh -(OCh-FDI-O)... 65 6..OCh (OCh-OCI)... 65 6.OTUk... 65 6..OTUk (OTUk-AIS)... 65 6.5ODUk... 66 6.5.ODUk (ODUk-AIS)... 66 6.5.ODUk (ODUk-OCI)... 67 6.5.ODUk (ODUk LCK)... 67 6.6... 68 6.6.AIS... 68 7... 68 7.... 68 7... 7 7... 7 7... 7 7... 7 7.GFP OPUk... 7 7.OPUk... 75 7..OPUk... 75 7..PRBS OPUk... 75 7.5 OPUk... 76 7.5. OPUk... 77 7.5. OPUk... 77 7.6 OPUk... 77 A6 RS55,9FEC... 78 I±0 ppm CBRG5CBR0GCBR0G... 80 II... 8

Optical Transport Network WDM G.709 G.709 Optical Transport Network G.709/Y.00.Prepublished ITU-TG.709 OTN 5

ITU-TG.709 OTN TTC G.709 ITU-T G.709 OTN ITU-TG.709 ITU SG5 ITU-T G.709 ODUkITU specific extensions00 ITU-T SG5 OPUkODUk OTUkITU-T G.709 ODUk OTUk OTN ODUk ITU-T G.709 OTN ODUk 00 OTN OTN 6

Optical Transport Network(G.709) ITU-T 7

ITU-TG.709.. - ITU-T G.65 - Characteristics of a single-mode optical fibre cable ITU-T G.65 - Characteristics of a dispersion-shifted single-mode optical fibre cable ITU-T G.655 - Characteristics of a non-zero dispersion shifted single-mode optical fibre cable ITU-T G.707 - Network Node Interface for the Synchronous Digital Hierarchy. ITU-T G.798 - Characteristics of Optical Transport Networks (OTN) Hierarchy Equipment Functional Blocks. ITU-T G.805 - Generic Functional Architecture of Transport Networks. ITU-T G.87 - Architecture of Optical Transport Networks. ITU-T G.959. - Optical Transport Network Physical Layer Interfaces. ITU-T I.. - B-ISDN user-network interface - Physical layer specification: General ITU-T M.00 - Designations for inter-operator networks ITU-T M.00 Amendment - Definition of The Management Interface for a Generic Alarm Reporting Control (ARC) Feature ITU-T O.50 - General requirements for instrumentation for performance measurements on digital transmission equipment.. G.707 8

.BIP-X X.Network Node Interface G.805.Adapted information (AI).Characteristic information (CI).5Network.6Subnetwork G.87.7Intra Domain Interface (IaDI).8Inter Domain Interface (IrDI).9Optical transport network (OTN).0Optical Multiplex Section (OMS) ().Optical Transmission Section (OTS).OTM-n[r].m..OTM (OTM-0.m, OTM-nr.m).. OCG....5 9

.6.7(Och[r]).7.(Och).7.(Ochr).8(OTUk[V]).8.OTUk (OTUk).8.OTUk (OTUkV).9(ODUk).9.ODUk (ODUkP).9.ODUk TCM (ODUkT).0(OPUk).(OCC[r])..OCC (OCC)o o 0

..OCC (OCCr).(OCG-n[r])..OCG (OCG-n) o..ocg (OCG-nr).(OMU-n, n>=).(opsn) G.65,G.65,G.655.5(ONNI).6OTM (OOS).7(OSC).8(OTH).9OTH.0(naOH)..CBR5G880kbit/s0ppm STM-6.CBR0G99580kbit/s0ppm STM-6.CBR0G989kbit/s0ppm STM-56.5(CMEP) -

5-9 5- -Och 5-5- - 5-5-. 0xYY YY 6 YY is a value in hexadecimal presentation R Reamplification, Reshaping and Retiming ACT Activation (in the TCM ACT byte) AI Adapted information AIS Alarm Indication Signal APS Automatic Protection Switching BDI Backward Defect Indication BDI-O Backward Defect Indication Overhead BDI-P Backward Defect Indication Payload BEI Backward Error Indication BI Backward Indication BIP Bit Interleaved Parity CBR Constant Bit Rate CI Characteristic information CM Connection Monitoring CMEP Connection Monitoring End Point CMOH Connection Monitoring overhead DAPI Destination Access Point Identifier EDC Error Detection Code EXP Experimental ExTI Expected Trace Identifier FAS Frame Alignment Signal FDI Forward Defect Indication FDI-O Forward Defect Indication Overhead FDI-P Forward Defect Indication Payload FEC Forward error correction GCC General Communication Channel IaDI Intra-Domain Interface IAE Incoming Alignment Error IrDI Inter-Domain Interface LSB Least Significant Bit MFAS MultiFrame Alignment Signal MS Maintenance Signal MSB Most Significant Bit

naoh non-associated overhead NNI Network node interface OCC Optical Channel Carrier OCCo Optical Channel Carrier - overhead OCCp Optical Channel Carrier - payload OCCr Optical Channel Carrier with reduced functionality OCG Optical Carrier Group OCGr Optical Carrier Group with reduced functionality OCI Open Connection Indication OCh Optical channel with full functionality OChr Optical channel with reduced functionality ODU Optical Channel Data Unit ODUk Optical Channel Data Unit-k OH Overhead OMS Optical multiplex section OMS-OH Optical multiplex section overhead OMU Optical Multiplex Unit ONNI Optical network node interface OOS OTM OTM Overhead Signal OPS Optical Physical Section OPU Optical Channel Payload Unit OPUk Optical Channel Payload Unit-k OSC Optical Supervisory Channel OTH Optical transport hierarchy OTM Optical transport module OTN Optical transport network OTS Optical transmission section OTS-OH Optical transmission section overhead OTU Optical Channel Transport Unit OTUk completely standardized Optical Channel Transport Unit-k OTUkV functionally standardized Optical Channel Transport Unit-k PCC Protection Communication Channel PLD Payload PM Path Monitoring PMI Payload Missing Indication PMOH Path Monitoring OverHead ppm parts per million PRBS Pseudo Random Binary Sequence PSI Payload Structure Identifier PT Payload Type RES Reserved for future international standardisation

RS Reed-Solomon SAPI Source Access Point Identifier Sk Sink SM Section Monitoring SMOH Section Monitoring OverHead So Source TC Tandem Connection TCM Tandem Connection Monitoring TCMOH Tandem Connection Monitoring OverHead TxTI Transmitted Trace Identifier UNI User to Network Interface

5. ITU-T G.87 ONNI ONNI ITU-T G.805 Row Column 7 8 5 6 FRAME ALIGNMENT AREA ODU SPECIFIC OVERHEAD AREA OTU SPECIFIC OVERHEAD AREA OPU SP ECIF IC OVERHEAD AR EA T580-00 (79) 5-/G.709 OTUk,ODUk OPUk 6. ITU-T G.87 OTN IrDI R n(otm-n)otn OTM-n OTM (OTM-n.m) OTM (OTM-0.m, OTM-nr.m) OTM OTN IrDI R 6. 6-5

6..OC G.87 G.87 (OCh)(OChr)OTN R (OTUk/OTUkV)OTN R (ODUk (ODUkT) (ODUkP) (OPUk) 6..OTM-n.m(n) OTM-n.m(n) (OTSn) (OMSn) (OCh) (OTUk/OTUkV) (ODUk) 6..OTM-nr.m OTM-0.m OTM-nr.m OTM-0.m (OPSn) (OChr) (OTUk/OTUkV) (ODUk 6

Clients (e.g. STM-N, ATM, IP, Ethernet) OPUk ODUk OTUkV ODUkP ODUkT OTUk OTUkV OTUk OCh substructure OCh OChr OMSn OTSn OPSn OTM-n.m OTM-0.m, OTM-nr.m Full functionality OTM interface 6-/G.709 OTN Reduced functionality OTM interface 6.OTN OTN 6-,6-,6-6-5 OTN OCh OTUk/OTUkV 7

Client OPUk OPUk OH OPUk Payload ODUk Path ODUk PMOH OPUk ODUk Tandem Connection ODUk TCMOH ODUk ODUk TC L TCMOH ODUk TC Lm ODUk TCMOH to 6 levels of ODUk Tandem Connection Monitoring OTUk[V] Section OTUk[V] OH OTUk[V] FEC OCh OCh OH OCh Payload OCG-n.m OC Co OC Co OC Co OC Co OC Co OCCp OCCp OCCp OCCp OCCp OMU-n.m OTM-n.m OTM COMMs OMSn OH OTSn OH OMSn Payload OTSn Payload OOS 6-/G.709 OTM-n.m 8

Client OPUk OPUk OH OPUk Payload ODUk Path ODUk PMOH OPUk ODUk Tandem Connection ODUk TCMOH ODUk ODUk TC L TCMOH ODUk TC Lm ODUk TCMOH to 6 levels of ODUk Tandem Connection Monitoring OTUk[V] Section OTUk[V] OH OTUk[V] FEC OChr OCh Payload OTM-0.m OPS0 6-/G.709 OTM-0.m Client OPUk OPUk OH OPUk Payload ODUk Path ODUk PMOH OPUk ODUk Tandem Connection ODUk TCMOH ODUk ODUk TC L TCMOH ODUk TC Lm ODUk TCMOH to 6 levels of ODUk Tandem Connection Monitoring OTUk[V] Section OTUk[V] OH OTUk[V] FEC OChr OCh Payload OCG-nr.m OCCp OCCp OCCp OCCp OCCp OTM-nr.m OPSn 6-/G.709 OTM-nr.m 9

Client Client_CI ODUkP/CL OPUk OCh_AI ODUkP Path CMEP ODUk ODUkT/ODUk ODUkT Tandem Connection CMEP ODUk OTUk/ODUk OTUkV/ODUk OTUk OTUk OTUkV OTUkV Optical Section CMEP OCh Network Layer OChr_CI OChr OCh/OTUk OCh/OTUkV OCh OCh OCh_CI OCh OH OCh OH λ λ λ λ 5 λ n λ OPS_AI OPS/OChr OCG-n OMS Network Layer OCh_CI OCh_CI_PLD λ OMS/OCh λ n λ 5 λ OCG-n OMS_AI OMS OMS_CI_PLD OMU-n OMS_CI λ λ OCh OH OCh_CI_OH OMS OH OMS_CI_OH OTM-0 OTM-nr (n>) OPS_CI OPS OTM-0 OTM-nr OPS Network Layer OTS Network Layer OTS/OMS OTS_AI OTS OTS_CI OTM-n OTS_CI_PLD OTM-n (n ) OOS λ OSC OMS OH OTS OH OTS_CI_OH COMMs 6-5/G.709 7./ 7- OTM-n OTS,OMS,OCh COMMS OOS 7. OPUk OPUk ODUk ODUk 0

OTUk[V]OTUk[V]OCh[r]OCh[r]OCC[r] 7. n(n)occ[r]ocg-n[r].m OCG-n[r].m OCC[r] OCG-n[r].m OTM-n[r].m OTM-n.m OSC OTM-n.m OTM-0.m OCCr OChr x i OTM-nr.m OCG-nr.m i+j+k n x k x j OCCr OCCr OChr OChr OTU[V] ODU OPU Client Signal OCC OCh OTU[V] ODU OPU Client Signal OTM-n.m OCG-n.m x i x j OCC OCh OTU[V] ODU OPU Client Signal x k i+j+k n OCC OCh OSC OOS OTS, OMS, OCh, COMMS OH Multiplexing Mapping 7-/G.709 OTM 7. OTUk 7- ODUk 7- OPUk 7- OTUk/ODUk/OPUk 7-

7-/G.709 OTU OTU OTU OTU OTU 55/8* 88 0kbit/s OTU 55/7*9 95 80kbit/s 0ppm OTU 55/6*9 8 0kbit/s -OTU 666 057. kbit/s(otu),0 709 5.6 kbit/s(otu), 08.559 kbit/s(otu) 7-/G.709 ODU ODU ODU ODU ODU 9/8* 88 0kbit/s ODU 9/7*9 95 80kbit/s 0ppm ODU 9/6*9 8 0kbit/s -ODU 98 775.6 kbit/s(odu),0 07 7.9 kbit/s(odu),0 9 8.98 kbit/s(odu) 7-/G.709 OPU OPU OPU OPU OPU 88 0kbit/s OPU 8/7*9 95 80kbit/s 0ppm OPU 8/6*9 8 0kbit/s -OPUk 88 0.000 kbit/s(opu ),9 995 76.96 kbit/s(opu ),0 50 59. kbit/s(opu ) 7-/G.709 OTUk/ODUk/OPUk OTU/ODU/OPU OTU/ODU/OPU OTU/ODU/OPU OTU/ODU/OPU 8.97 s.9 s.05 s -

8.(OTM-n.m,OTM-nr.m,OTM-0.m) OTM IrDI OTM OTM IrDI 8.OTM(OTM-0.m,OTM-nr.m) OTM-n R n OTUk R OTUk[V]OTM-0.m OTM-nr.m OTM OTM-0.m OTM-nr.m OSC/OOS OTM OTM-0.m OTM-6r.m 8..OTM-0.m OTM-0.m R OTM-0.m (8-)OTUk OTM-0.(OTU[V]); OTM-0.(OTU[V]); OTM-0.(OTU[V]); OTM-0.m 8- OTM-0.m OSC OOS OTM-0. OCCr OChr OTU[V] ODU OPU Client Signal OTM-0. OCCr OChr OTU[V] ODU OPU Client Signal OTM-0. OCCr OChr OTU[V] ODU OPU Client Signal Mapping 8-/G.709 OTM-0.m 8..OTM-6r.m OTM-6r.m R 6 OTM-6r.m OTM-6r.( i( i6)otu[v]); OTM-6r.( j( j6)otu[v]);

OTM-6r.( k( k6)otu[v]); OTM-6r.( i( i6)otu[v], j( j6)otu[v],k( k6)otu[v] OTM-6r.( i( i6)otu[v], j( j6)otu[v]i+j6); OTM-6r.( j( j6)otu[v],k( k6)otu[v]j+k6); OTM-6r.m i+j+k6); OTM-6r.m OCCr#0 OCCr#5(6-5) OTM-nr.m OOS OCCrs OTUk[V]OCCrs OTM-6r.m OTM-6r.m 8- OTM-6r.m OPS OTUk[V] SMOH OTM-6r.m (TIM)OTUk[V]

OTM-6r. OCG-6r. x i OCCr OChr OTU[V] ODU OPU Client Signal i 6 OTM-6r. OCG-6r. x j OCCr OChr OTU[V] ODU OPU Client Signal j 6 OTM-6r. OCG-6r. x k OCCr OChr OTU[V] ODU OPU Client Signal k 6 OTM-6r. OCG-6r. x j OCCr OChr OTU[V] ODU OPU Client Signal i+j 6 x i OCCr OChr OTU[V] ODU OPU Client Signal j+k 6 x k OCCr OChr OTU[V] ODU OPU Client Signal OTM-6r. OCG-6r. x j OCCr OChr OTU[V] ODU OPU Client Signal OCCr OChr OTU[V] ODU OPU Client Signal x k OTM-6r. OCG-6r. x j OCCr OChr OTU[V] ODU OPU Client Signal x i i+j+k 6 OCCr OChr OTU[V] ODU OPU Client Signal Multiplexing Mapping 8-/G.709 OTM-6r.m 5

8.OTM(OTM-n.m) OTM-n.m R 6 OTM-n : -OTM-n. ( i (i n) OTU[V] ) -OTM-n. (j (j n) OTU[V] ) -OTM-n.. ( k (k n) OTU[V] ) -OTM-n. ( i (i n) OTU[V], j (j n) OTU[V], k (k n) OTU[V] i + j + k n) -OTM-n. ( i (i n) OTU[V], j (j n) OTU[V] i + j n) -OTM-n. ( j (j n) OTU[V] k (k n) OTU[V] j + k n) OTM-n.m OTM-n.m m OSC(8-)OCC n, m OSC 6

OTM-n. OCG-n. x i OCC OCh OTU[V] ODU OPU Client Signal i n OSC OOS OTS, OMS, OCh, COMMS OH OTM-n. OCG-n. x j OCC OCh OTU[V] ODU OPU Client Signal j n OSC OOS OTS, OMS, OCh, COMMS OH OTM-n. OCG-n. x k OCC OCh OTU[V] ODU OPU Client Signal k n OSC OOS OTS, OMS, OCh, COMMS OH OTM-n. OCG-n. x j OCC OCh OTU[V] ODU OPU Client Signal i+j n x i OCC OCh OTU[V] ODU OPU Client Signal OSC OOS OTS, OMS, OCh, COMMS OH j+k n x k OCC OCh OTU[V] ODU OPU Client Signal OTM-n. OCG-n. x j OCC OCh OTU[V] ODU OPU Client Signal OSC OOS OTS, OMS, OCh, COMMS OH OCC OCh OTU[V] ODU OPU Client Signal x k OTM-n. OCG-n. x j OCC OCh OTU[V] ODU OPU Client Signal x i i+j+k 6 OCC OCh OTU[V] ODU OPU Client Signal OSC OOS OTS, OMS, OCh, COMMS OH Multiplexing Mapping 8-/G.709 OTM-n.m 7

9.ONNI 9.OTM-0.m OTM-0. OTM-0. G.959. OTM-0. 9.OTM-6r.m OTM-6r.OTM-6r.OTM-6r. G.959. OTM-6r.OTM-6r.OTM-6r. 9.OTM-n.m OTM-n.m 0.(OCh) OCh R OCh OTUk (STM-NGbE)OTM 0.OCh(OCh) (OCh)0- :OCh Och OCh Overhead OCh Payload 0-/G.709 Och 8

0. OCh(OChr) (OChr)0- Ochr OChr Payload 0-/G.709 Ochr.(OTU) OTUk V ODUk OTUk OTUkV ( );II.OTUk OTUk (k=,,)oduk - (FEC) 56 FEC ODUk ODUk 9 OTUk 080 8 OTUk Table 7-9

8 ODUk 5 8 85 080 FA OH OTUk OH OTUk FEC RS(55,9) or all-0's OTUk ( x 56 bytes) T500-00 (79) /G.709 OTUk OTUk (FEC)-RS(55,9) FEC FEC (all-0 ) RS(55,9) FEC A/G.709 FEC FEC FEC FEC (OTUk FEC ) OTUk (-) Column Row MSB 5 6 7 8 LSB 080 T50-00 (79) /G.709 OTUk 0

. OTUk ONNI 0 OTUk 6555 +x+ x + + 6 - OTUk "FFFF"(HEX)MFAS 6 OTUk (FAS) FEC OTUk Data In OTUk Clock D Q S D Q S D Q S OTUk MSB of MFAS byte D Q S D Q D Q D Q D Q D Q D Q D Q D Q D Q D Q D Q D Q S S S S S S S S S S S S -/G.709 T50-00 (79) Scrambled Data Out.(ODUk).ODUk ODUk (k=,,)- 8 ODUk ODUk ; OPUk ODUk ODUk - OTUk ODUk 58 OPUk

Column Row 5 8 ODUk Overhead area OPUk area ( x 80 bytes) Area reserved for FA and OTUk Overhead. T50-00 (79) /G.709 ODUk.(OPUk) OPUk(k=,,)- 80 OPUk OPUk ; OPUk OPUk 56 OPUk OPUk 78 OPUk -OPUk ODUk OPUk Column 5 Row O 6 7 8 PU ar k Ov OPUk Payload area ( x 808 bytes) T50-00 (79) /G.709 OPUk.OTM (OOS) OTM (OOS)OTSOMSOCh OOS OOS OSC

OOS OOS / 5. OTSOMSOch 5- OTUkODUkOPUk 5-5- 5. 5..OPUk OH OPUk OH OPUk OPUk OPUk OH OPUk OH 5.9 5..ODUk OH ODUk OH ODUk ODUk ODUk OH end-to-end ODUk 6 ODUk OH ODUk TC OH OH 5.6 5.8 5..OTUk OH OTUk OH OTUk OTUk OH OTUk OH 5.6 5.7 OTUkV OH 5.7. 5..Och OH Och OH Och OTUk Och OH Och Och OH 5.5 5..5OMS OH OMS OH OMU OCG OMS OH OMU OMS OH 5. 5..6OTS OH OTS OH OTM

OTS OH OTM OTS OH 5. 5..7COMMS OH COMMS OH OTM COMMS OH TTI BDI-O FDI-O FDI-P BDI-O FDI-O n BDI-P BDI-P FDI-P OTSn PMI OMSn PMI OCh OCI General Management Communications 5-/G.709 OOS OTSnOMSOch

Row Column 7 8 5 8 FA OH OTUk OH 85 080 OTUk FEC ( x 56 bytes) SM TTI BIP-8 0 5 6 7 8 Column # 5 6 7 8 9 0 FAS MFAS SM GCC0 RES 5 6 SAPI DAPI BEI BDI IAE RES FA: FAS: MFAS: SM: GCC: RES: Frame Alignment Frame Alignment Signal MultiFrame Alignment Signal Section Monitoring General Communication Channel Reserved for future international standardisation TTI: Trail Trace Identifier BIP8: Bit Interleaved Parity - level 8 BEI: Backward Error Indication BDI: Backward Defect Indication IAE: Incoming Alignment Error DAPI: Destination Access Point Identifier SAPI: Source Access Point Identifier 6 Operator Specific 5-/G.709 OTUk OTUk 5

Column Row 56 7 8 PM and TCMi (i=..6) TTI BIP-8 ODUk Overhead OPUk Overhead OPUk Payload ( x 808 bytes) 0 5 6 SAPI 5 6 7 8 BEI BDI STAT BIP8 Parity Block DAPI OPUk OH Row# 5 6 7 8 Frame Alignment overhead RES TCM ACT TCM6 TCM TCM TCM Column # 9 0 5 6 TCM5 OTUk overhead PM TCM EXP FTFL OPUk overhead 6 Operator Specific 5 6 Mapping specific PSI GCC GCC APS/PCC RES PM: TCM: SAPI: DAPI: RES: ACT: Path Monitoring FTFL: Tandem Connection Monitoring EXP: Source Access Point Identifier GCC: Destination Access Point Identifier APS: Reserved for future international standardisation PCC: Activation/deactivation control channel Fault Type & Fault Location reporting channel Experimental General Communication Channel Automatic Protection Swiching coordination channel Protection Communication Control channel TTI: Trail Trace Identifier BIP8: Bit Interleaved Parity - level 8 BEI: Backward Error Indication BDI: Backward Defect Indication STAT: Status PSI: Payload Structure Identifier PT: Payload Type 0 55 PT RES 5-/G.709 ODUk ODUk OPUk 6

5. TTI 5-6 TTI[0]0 SAPI[0] TTI[]TTI[5]5 SAPI[]SAPI[5] TTI[6]0 DAPI[0] TTI[7]TTI[]5 DAPI[]DAPI[5] TTI[]TTI[6] 0 5 6 7 8 5 6 7 8 SAPI[0] 0 0 0 0 0 0 SAPI[] SAPI[] SAPI[5] DAPI[0] DAPI[] DAPI[] DAPI[5] Source Access Point Identifier Destination Access Point Identifier Operator Specific 6 5-/G.709 T580-00 (79) TTI APIs 7

ODUkOTUkOTM SAPIDAPI NS 5-5 T.507 8

IS character # NS character # 5 6 7 8 9 0 5 CC ICC UAPC CC ICC UAPC CC ICC UAPC CC ICC UAPC CC ICC UAPC CC ICC UAPC 5-5/G.709 T590-00 (79) ISO66 G/PCC ISO66 USAFRA UAPCITU ICC ITU M.00 ITU-T6 left-justified ITU 0 6 5.OTS OH OTM-n OTSn OTSn-TTI OTSn-BDI-P OTSn-BDI-O OTSn-PMI 5..OTS TTI OTSn-TTI OTSn 5. 6 TTI 5..OTS BDI-P OTSn OTSn-BDI-P OTSn OTSn 5..OTS BDI-O OTSn OTSn-BDIO OTSn OTSn 9

5..OTS PMI OTS PMI OTS 5.OMS OH OTM-n OMSn OMSn-FDI-P OMSn-FDI-O OMSn-BDI-P OMSn-BDI-O OMSn-PMI 5..OMS FDI-P OMSn OMSn-FDI-P OMSn 5..OMS FDI-O OMSn OMSn-FDI-O OMSn 5..OMS BDI-P OMSn OMSn-BDI-P OMSn OMSn 5..OMS BDI-O OMSn OMSn-BDI-O OMSn OMSn 5..5OMS PMI OMS PMI OMS OCCp 5.5Och OH OTM-n Och Och-FDI-P Och-FDI-O Och-OCI 5.5.Och FDI-P Och Och-FDI-P Och 0

5.5.Och FDI-O Och Och-FDI-O Och 5.5.Och OCI Och OCI Och Och

5.6OTUk/ODUk 5.6.OTUk/ODUk OTUk/ODUk 5-6 OTUk/ODUk OTUk ODUk 5 6 7 8 Column # 9 0 5 6 FAS MFAS OTUk Overhead Row # ODUk Overhead OPUk Overhead T5500-00 (79) 5-6/G.709 OTUk/ODUk 5.6.OTUk/ODUk 5.6.. ( FAS ) 6 OTUk-FAS (5-7) OTUk 6 OA 00OA 000 000 FAS OH Byte FAS OH Byte FAS OH Byte FAS OH Byte FAS OH Byte 5 FAS OH Byte 6 5 6 7 8 5 6 7 8 5 6 7 8 5 6 7 8 5 6 7 8 5 6 7 8 OA OA OA OA OA OA T550-00 (79) 5-7/G.709 5.6.. ( MFAS ) OTUkODUk OTUk/ODUk TTI PSI OTUk/ODUk ( MFAS ) OTUk/ODUk 5-8) MFAS OTUk/ODUk 56 OTUk/ODUk 8 6

MFAS OH Byte 5 6 7 8 : 0000 0000 0000 000 0000 000 0000 00 0000 000 : : 0 0000 0000 0000 000 : MFAS sequence T550-00 (79) 5-8/G.709 5.7 OTUk 5.7.OTUk OTUk 5-95-0 Column # 5 6 7 8 9 0 5 6 Frame Alignment Overhead SM GCC0 RES Row # ODUk Overhead OPUk Overhead T550-00 (79) 5-9/G.709 OTUk

SM TTI BIP-8 0 5 6 SAPI DAPI 5 6 7 8 BEI BDI IAE RES T550-00 (79) Operator Specific 6 5-0/G.709 OTUk 5.7.OTUk 5.7.. OTUk OTUk ( SM ) SM (5-0 ): ( TTI ) (BIP-8) ( BDI ) ; ( BEI ) ; ( IAE ) ; ( RES ) 5.7... OTUk SM ( TTI ) ( TTI )5. 6 TTI 6 TTI OTUk ( 5.6.. ) 6 TTI 0 OTUk 0000 0000 ( 0x00 ) 000 0000 ( 0x0 ) 000 0000 ( 0x80 )00 0000 ( 0xC0 ) 5.7... OTUk SM (BIP-8) 8 (BIP-8) BIP-8 BIP

OTUk BIP-8 OTUk OPUk (5 8 )OTUk i+ (5- )OTUk BIP-8 5 8 Frame i Frame i+ Frame i+ BIP8 BIP8 BIP8 OPUk BIP8 T5550-00 (79) 5-/G.709 OTUk SM BIP-8 5.7... OTUk SM ( BDI ) ( BDI ) BDI OTUk 0 5.7... OTUk SM ( BEI ) ( BEI ) OTUk BIP-8 9 0-8 7 (5-) 5-/G.709 OTUk SM BEI 5

OTUk SM BEI BIP 0000 0 000 000 00 000 00 5 00 6 0 7 000 8 00 0 5.7...5 OTUk SM ( IAE )S-CMEP S-CMEP IAE 0 S-CMEP OTUk 5.7...6 OTUk SM ( RES )00 5.7.. OTUk 0 ( GCC0 ) OTUk byte OTUk OTUk 5.7.. OTUk OTUk 5.7.OTUkV OTUkV 5. OTUk ( 5.7.. ) 6

5.8 ODUk 5.8.ODUk ODUk 5-,5-5- Column # 5 6 7 8 Frame Alignment overhead 9 0 5 6 OTUk overhead Row# RES TCM ACT TCM TCM TCM TCM6 TCM5 TCM PM EXP FTFL OPUk overhead GCC GCC APS/PCC RES 5-/G.709 ODUk PM TTI BIP-8 0 5 6 SAPI DAPI 5 6 7 8 BEI BDI STAT Operator Specific 6 5-/G.709 ODUk 7

TCMi TTIi BIP-8i 0 5 6 SAPI DAPI 5 6 7 8 BEIi BDIi STATi Operator Specific 6 5-/G.709 ODUk #i 5.8.ODUk 5.8.. ODUk ODUk ( PM )0 PM (5- ): ( TTI ); (BIP-8); ( BDI ) ; ( BEI ) ; ( STAT ) PM STAT ( ODUk-AISODUk-OCI ODUk-LCK )(all-00 0000 00 )6.5 5.8... ODUk PM ( TTI ) 5. 6 TTI TTI 6 TTI OTUk ( 5.6.. ) 6 TTI 0 OTUk 0000 0000 ( 0x00 ) 000 0000 ( 0x0 ) 000 0000 ( 0x80 )00 0000 ( 0xC0 ) 5.8... ODUk PM (BIP-8) 8 (BIP-8) BIP-8 BIP 8

ODUk BIP-8 ODUk OPUk (5 8 )ODUk i+ (5-5 )ODUk BIP-8 5 8 Frame i Frame i+ Frame i+ BIP8 BIP8 BIP8 OPUk BIP8 T5590-00 (79) 5-5/G.709 ODUk PM BIP-8 5.8... ODUk M ( BDI ) ( BDI ) BDI ODUk 0 5.8... ODUk M ( BEI ) ( BEI ) ODUk BIP-8 9 0-8 7 (5-) 9

5-/G.709 ODUk PM BEI ODUk PM BEI BIP 0000 0 000 000 00 000 00 5 00 6 0 7 000 8 00 0 5.8...5 ODUk PM ( STAT ) ( STAT )(5- ) P-CMEP 00 5-/G.709 ODUk PM PM 678 000 00 00 0 00 0 : ODUk-LCK 0 : ODUk-OCI : ODUk-AIS 50

5.8.. ODUk ODUtcmODUk TCM ODUk G.805 G.87 UNI UNI ;ODUk ( ) NNI NNI ;( ) +::n SP 6 TCMTCM.,TCM6 TCM (5-) TTI; (BIP-8); BDI; BEI; STATTCM STAT TCM 0000 0000 ODUk-AIS, ODUk-OCI, ODUk-LCK 6.5 TCM 5.8...6 ODUk 5-6 A-A/B-B/C-C A-A/B-B B-B/B-B 5

TCM6 TCM5 TCM6 TCM5 TCM6 TCM5 TCM6 TCM5 TCM6 TCM5 TCM6 TCM5 TCM6 TCM5 TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM A B C C B B B A C - C B - B B - B A - A TCMi TCM OH field not in use TCMi TCM OH field in use Figure 5-6/G.709 ODUk 5-7 (B-B and C-C) TCM6 TCM6 TCM6 TCM6 TCM6 TCM5 TCM5 TCM5 TCM5 TCM5 TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM TCM A B C B C A C - C B - B A - A TCMi TCM OH field not in use TCMi TCM OH field in use Figure 5-7/G.709 ODUk 5

5.8... ODUk TCM (TTI) 5. 6 TTI 6 TTI ODUk 5.6.. 6 TTI ODUk 0000 0000 (0x00), 000 0000 (0x0), 000 0000 (0x80) and 00 0000 (0xC0) 5.8... ODUk TCM (BIP-8) BIP-8 BIP-8 BIP EDC ODUk BIP-8 ODUk I OPUk58 ODUkTCMBIP-8 ODUk I5-8 5 8 Frame i Frame i+ Frame i+ BIP8 BIP8 BIP8 OPUk BIP8 T560-00 (79) Figure 5-8/G.709 ODUk TCM BIP-8 5.8... ODUk TCM (BDI) BDI BDI ODUk 5.8... ODUk TCM (BEI) BEIODUk BPI-8 5

5- Table 5-/G.709 ODUk TCM BEI ODUk TCM BEI bits BIP violations 0000 0 000 000 00 000 00 5 00 6 0 7 000 8 00 to 0 5.8...5 ODUk TCM (STAT) STAT TC-CMEP TC-CMEP 5-5 P-CMEP "000" TC-CMEP IAETC-CEMP 00 IAE 00 TC-CMEP ODUk 5

Table 5-5/G.709 ODUk TCM Status TCM byte, bits 678 Status 000 no source TC 00 in use without IAE 00 in use with IAE 0 reserved for future international standardisation 00 reserved for future international standardisation 0 maintenance signal: ODUk-LCK 0 maintenance signal: ODUk-OCI maintenance signal: ODUk-AIS 5.8...6 TCM TC-CMEP 6 TCMj TCM TCMj TCMi TCM..TCM MAX TCM max+ TCM - ODUk TCM TCM TCM ODUk TCMOH -TCM..TCM6 TCM -SPUNI TCM -NO, NO, NO TCM, TCM, TCM5, TCM6: NONO TCM5,TCM6 - NO (NO ): TCM5, TCM6. 55

NO NO NO USER USER ODUk Path NO ODUk Path Network Operator Network Operator Network Operator Network Operator Network Operator Network Operator User Network Operator Network Operator User TCM6 TCM5 TCM TCM TCM TCM Service Provider User TCM Overhead Field Figure 5-9/G.709 TCM 5.8...7 ODUk / TCM / 56

5.8.. ODUk (GCC, GCC) ODUk ODUk -R GCC GCC ODUk 5.8.. ODUk (APS/PCC) ODUk-APS/PCC ODUk APS/PCC 5.8..5 ODUk FIFL 56 FIFLODUk ODUk 56 FTFL ODUk 56 FTFL ODUk 00000000 56 FTFL ODUk 0000000 56 FTFL ODUk 0000000 56 FTFL 5-9 8 FTFL 7 FTFL 0 7 8 9 55 Forward field Backward field T5690-00 (79) Figure 5-0/G.709 FTFL 5- / // 57

0 9 0 7 Operator Identifier Operator Specific field field Fault Indication Field Forward 8 9 7 8 55 Operator Identifier field Operator Specific field Fault Indication Field Backward T5700-00 (79) Figure 5-/G.709 / 5.8..5. / FTFL FTFL 5-6 0000 0000 0000 000 0000000 58

Table 5-6/G.709 Fault Indication Code Definition 0000 0000 No Fault 0000 000 Signal Fail 0000 000 Signal Degrade 0000 00... Reserved for Future International Standardisation 5.8..5. / 5- ISO66 /G/PCC 9 ISO66 USA FRA ITU (ICC)ICC ITU-T M.00 ITU-T ITU (ICC) 59

Byte Allocation in Backward Field Byte allocation in Forward Field 9 0 5 6 7 0 5 6 7 8 Country Code G/PCC G/PCC ICC ICC National Segment Code NUL Padding NUL Padding G/PCC G/PCC G/PCC ICC ICC ICC NUL Padding NUL Padding NUL Padding G/PCC ICC NUL Figure 5-/G.709 T570-00 (79) 5.8..6. / 5-5.8..6 ODUk (EXP) ODUk ODUk ODUk ODUkOH EXP EXP 5.8..7 ODUk (RES) ODUODUk 60

5.9OPUk 5.9.OPUk OPUk OPUk OPUk PSI PT 5- Column # 5 6 7 8 9 0 5 6 Frame Alignment overhead OTUk overhead Row # ODUk overhead Mapping specific PSI 0 PT RES 5 55 T570-00 (79) 5-/G.709 OPUk 5.9.OPUk 5.9.. OPUk (PSI) OPUk 56 (PSI) OPUk 5 56 PSI ODUk PSI[0]ODU0000 0000 PSI[]ODU0000 000 PSI[]ODU0000 000 6

PSI[0] PSI[]PSI[55]PT0x0()PTs 80-0x8F() 5.9... OPUk (PT) OPUk PSI[0] 5-7 6

5-7/G.709 MSB LSB Hex code Interpretation 5 6 7 8 (NOTE ) 0 0 0 0 0 0 0 0 Experimental mapping (NOTE ) 0 0 0 0 0 0 0 0 asynchronous CBR mapping, see 7. 0 0 0 0 0 0 0 bit synchronous CBR mapping, see 7. 0 0 0 0 0 0 0 0 ATM mapping, see 7. 0 0 0 0 0 0 05 GFP mapping, see 7. 0 0 0 0 0 0 0 0 bit stream with octet timing mapping, see 7.5. 0 0 0 0 0 0 bit stream without octet timing mapping, see 7.5. - 5 reserved for future international standardisation 0 0 0 0 55 Not available (NOTE ) 56-65 reserved for future international standardisation 0 0 0 0 66 Not available (NOTE ) 67-7F reserved for future international standardisation 0 0 0 x x x x 80-8F reserved codes for proprietary use (NOTE ) 90 - FC reserved for future international standardisation 0 FD NULL test signal mapping, see 7.. 0 FE PRBS test signal mapping, see 7.. FF Not available (NOTE ) NOTE- 8 NOTE-,ODUk NOTE-"0" OTN NOTE-6 6

5.9... OPUk RES 55 PT 0x0,0x80-0x8F OPUk PSI OPUk PSI[]PSI[55] 5.9.. OPUk 7 OPUk 5 6 6 7 6. (AIS) AIS AIS FDI) FDI FDI NOTEAIS FDI AIS FDI FDI OTM (OOS) (OCI) OCI OCI (LCK) (PMI), PMI LOS 6.OTS 6..OTS (OTS-PMI) OTS-PMI OTS 6.OMS OMS OMS-FDI-P,OMS-FDI-O OMS-PMI 6

6..OMS -(OMS-FDI-P) OMS-FDI-P OTS OMS 6..OMS -(OMS-FDI-O) OMS-FDI-O OOS OOS OMS OH 6..OMS (OMS-PMI) OMS-PMI OCCs 6.OCh OCh OCh-FDI-P,OCh-FDI-O OCh-OCI 6..OCh -(OCh-FDI-P) OCh-FDI-P OMS OCh OTUk OCh-FDI ODUk-AIS 6..OCh -(OCh-FDI-O) OCh-FDI-O OOS OOS OCh OH 6..OCh (OCh-OCI) OCh-OCI OCh ( NOTEOCI OTUk (M.00 ) 6.OTUk 6..OTUk (OTUk-AIS) OTUk-AIS(6-)AIS (6.6.)OTUk (0560bit) PN- (07bit) PN- OTUk NOTEOTUk-AIS OTN 65

5 8 85 080 Repeating PN- sequence 6-/G.709 OTUk-AIS 6.5ODUk ODUk ODUk-AIS,ODUk-OCI ODUk-LCK 6.5.ODUk (ODUk-AIS) ODUk-AIS (FA OH),OTUk (OTUk OH)ODUK FTFL ODUk all""(6-) ODUk-AIS OTM ODUk GCC,GCC,EXP APS/PCC ODUk-AIS OTM ODUk-AIS PM TCMi ODUk STAT 7 8 7 8 FA OH OTUk OH STAT STAT STAT STAT STAT STAT STAT FTFL All-'s pattern 6-/G.709 ODUk-AIS 66

6.5.ODUk (ODUk-OCI) ODUk-OCI (FA OH),OTUk (OTUk OH)ODUK FTFL ODUk "00 00"(6-) NOTE "00 00"PM TCMi ODUk STAT "0" ODUk-OCI OTM ODUk GCC,GCC,EXP APS/PCC ODUk-OCI OTM ODUk-OCI PM TCMi ODUk STAT 7 8 7 8 FA OH OTUk OH STAT STAT STAT STAT STAT STAT STAT Repeating "00 00" pattern 6-/G.709 ODUk-OCI 6.5.ODUk (ODUk LCK) ODUk-LCK (FA OH),OTUk (OTUk OH)ODUK FTFL ODUk "00 00"(6-) NOTE "00 00"PM TCMi ODUk STAT "0" ODUk-LCK OTM ODUk GCC,GCC,EXP APS/PCC ODUk-LCK OTM ODUk-LCK PM TCMi ODUk STAT 67

7 8 7 8 FA OH OTUk OH STAT STAT STAT STAT STAT STAT STAT Repeating "00 00" pattern 6-/G.709 ODUk-LCK 6.6 6.6.AIS AIS 07 PN- 5./O.50 + x 9 + D Q D Q D Q D Q D Q D Q D Q D Q D Q D Q D Q Generic-AIS Clock 6-5/G.709 AIS 7. 7. 68

Row Column 5 6 7 8 8 RES RES RES PSI JC JC JC NJO PJO OPUk OH PSI 0 55 PT RES OPUk Payload ( x 808 bytes) 5 6 7 8 JC Reserved JC T5770-00 (79) 7-/G.709 7-/G.709 JC [7,8] NJO PJO 00 Justification byte data byte 0 data byte data byte 0 not generated Justification byte justification byte 69

7-/G.709 JC [7,8] NJO PJO 00 Justification byte data byte 0 0 not generated 7-/G.709 JC [7,8] NJO PJO 00 Justification byte data byte 0 data byte data byte 0 (Note) Justification byte data byte Justification byte justification byte 70

7.. PSI RES RES RES 5 JC JC 6 7 8 D D D D D D NJO JC PJO D 805D 805D 805D 805D 8 D D D D 7-/G.709 T5780-00 (79) 7.. 7

PSI RES RES RES 5 NJO JC JC JC 6 PJO 7 90 905 90 9 8 6D 8 6D 8 6D 5D + 7 6D 6FS 6FS 6FS 6FS 9 6D 9 6D 9 6D 9 6D 8 T5790-00 (79) 7-/G.709 7.. PSI RES RES RES 5 NJO JC JC JC 6 PJO 7 6 65 80 8 78 6D 6FS 79 6D 78 6D 78 6D 5D + 77 6D 6FS 6FS 6FS 79 6D 79 6D 79 6D 5 55 6FS 6FS 6FS 6FS 560 56 79 6D 79 6D 79 6D 79 6D 8 7-/G.709 T5800-00 (79) 7

7. 5 6 7 8 PSI RES RES RES RES RES RES RES OPUk Overhead PSI 0 PT RES OPUk Payload ATM cell T580-00 (79) 55 5 bytes 7-5/G.709 7

7.GFP OPUk GFPGFP OPUk 7-6GFP GFP OPUk GFP GFP GFP GFP GFP GFP OPUk GFP 5 6 7 8 PSI RES RES RES RES RES RES RES OPUk Overhead PSI 0 PT RES GFP Frame OPUk Payload GFP Idle 55 GFP Header GFP Payload 7-6/G.709 OPUk GFP OPUk GFP OPUk PTPSI RES GFP OPUk x 808 7

7.OPUk 7..OPUk OPUk 7-7 Row Column 5 6 7 8 8 RES RES RES RES RES RES All-0's pattern PSI RES OPUk OH PSI 0 PT RES OPUk Payload ( x 808 bytes) T580-00 (79) 55 7-7/G.709 OPUk OPUk OPUk PT PSI RES OPUk x 808 7..PRBS OPUk O.50/5.8,7,8,67 -OPUk,7,8,67 8 ODU 8 8D 7-8 75

PS I RES RES RES 5 RES RES RES RES 6 7 8 8D 8D 8D 8D 8D 8D 8D 8D 805x 8D 805x 8D 805x 8D 805x 8D 8D 8D 8D 8D 8 OPUk OH PSI 0 PT RES OPUk Payload ( x 808 bytes) T580-00 (79) 55 7-8/G.709 OPUk,7,8,67 OPUk PRBS OPUk PT PSIRES PRBS OPUk x 808 7.5 OPUk OPUk OPUk OPUk 7-9 OPUk OPUk Row Column 5 6 7 8 8 CS CS CS PSI CS CS CS CS OPUk OH PSI 0 PT RES OPUk Payload ( x 808 bytes) T5850-00 (79) 55 76

7-9/G.709 OPUk OPUk PTPSI CSCS OPUk x 808 7.5. OPUk OPUk 7.5. OPUk 8 OPUk 7.6 OPUk 77

A6 RS55,9FEC OTU-k FECRS55,96 RS55,9FEC FEC OTU A..6 FEC 9 0 55 FEC OTU X+6 (i-) (i=...55) Information bytes Parity check bytes FEC sub-row #6 9 0 5 5 Information bytes 9 0 Parity check bytes FEC sub-row # 5 5 Information bytes 9 0 Parity check bytes FEC sub-row # 5 5... 6 Information bytes 8 8 5 8 6... 8 0 Parity check bytes 0 8 0 OTU row T5860-00 (79) A./G.709 FEC 5 i ( z) = ( z ) G α αx 8 + x + x + x + FEC A.FEC i= 0 D j (j=6... 5) GF(56) α α α d 7j d 0j 78

D 5 FEC D 6 9 R j (j=0... 5) GF(56) α α α r 7j r 0j R 5 FEC 0 R 0 55 R(z) modgf(56)g(z) GF(56) + + + + transmission order within FEC code word 8 9 0 5 55 FEC sub-row D 5 D 5 D 5 D 5 D j D 7 D 6 R 5 R R j R R 0 5 6 7 8 5 6 7 8 d 7j d 6j d 5j d j d j d j d j d 0j r 7j r 6j r 5j r j r j r j r j r 0j A./G.709 FEC RS(55,9)dmin=7 FEC 8 FEC 6 79

I±0 ppm CBRG5 CBR0G CBR0G () 7. ±0 ppm CBRG5CBR0GCBR0G k //(pnz) k k k 7.,, 9/8, 9/7, 9/6 88 0 kbit/s, 9 95 80 kbit/s, 9 8 0 kbit/s k ±0 ppm pnz 7. pnz k PJO (NJO) pnz ()0 - + α ( α )αα ) N S T β N f =k =(/) =k () =k k =k () N f : N f = S β T k ( ()(808) = 5)(N) α (): β T = N + α S 5 80

()αk ()α () α α[, ] (9/8)S ()(8)/T 8 = ( )(8) = 5 9 ST ()N=0 (): α = 5( β ) k ±0 ppm β 0.99996.0000 ()α: 0.6098 α + 0. 6098 (9/7)S ()(8)/T 7 = ( )(8) = 568 9 : (), ST N=6 () α = 568β + 6 5 = 568( β ) k ±0 ppm β 0.99996.0000 (7)α: 0.6067 α + 0. 6067 (9/6)S ()(8)/T 6 = ( )(8) = 50 9 ST ()N=8 (): α = 50β + 8 5 = 50( β ) k ±0 ppm β 0.99996.0000 (7)α: 0.606 α + 0. 606 8

II k II. k k k k II. k k k II. k II. k II.5 k II.6 k k k k II.7 k ) k Column Row 5 6 7 8 85 080 FA OH OTUk OH Row RS(55,9) FEC redundancy OTUk Payload =ODUk Row RS(55,9) FEC redundancy Row RS(55,9) FEC redundancy Row RS(55,9) FEC redundancy II./G.709 k (RS(55,9) ) 8

Row Column 5 6 7 FA OH OTUkV OH 8 85 080 OTUkV Payload =ODUk OTUkV FEC II./G.709 k Row Column 5 6 7 FA OH OTUkV OH 8 85 080 OTUkV Payload =ODUk OTUkV FEC Fixed Stuff (ALL-0's) II./G.709 k Row Column 5 6 7 FA OH OTUkV OH OTUkV Payload =ODUk 8 85 X OTUkV FEC II./G.709 k 8

Column Row 5 6 7 FA OH OTUkV OH 8 OTUkV Payload =ODUk II.5/G.709 k Column Row X X + X +X X +X + X +X +X OTUkV Overhead (Y x X bytes) OTUkV Payload =ODUk OTUkV FEC (Y x X bytes) Y II.6/G.709 k Column Row X X + X +X OTUkV Overhead (Y x X bytes) OTUkV Payload =ODUk Y II.7/G.709 k 8

k k II.II.5 II.6 II.7 k k k k k k k k k k k k k [] k k k X X + X +X X +X + X +X +X OTUkVOverhead (Y x X bytes) OTUkV Payload (Y x X bytes) OTUkV FEC (Y x X bytes) Y 5 6 7 8 FA OH ODUk Overhead OPUk Overhead ODUk Payload ( x 808 bytes) II.8/G.709 k k 85