OTN Optical Transport Network

Transcription

1 OTN Optical Transport Network José María Pindado Buendía Engineering & Technology, EMEA November 2016

2 OTN ground Architecture Overhead Structure OTN Functioning FEC OTN Bit Rates OTN - Mapping Coding Gain Recommended Test-Scenarios OTN-Layer Agenda BER Error/Alarm Pass-through-Mode (OH-Overwrite) FEC Client to Client (Based on RFC2544 / Y.1564) 2 Copyright ANRISTU

3 OTN ground Architecture Overhead Structure Functioning FEC Coding Gain OTN Bit Rates OTN - Mapping 3 Copyright ANRISTU

4 New Technologies: Network Changes Common Carrier Class Network From Mobile to Core From Copper to Fiber From 2G to 4G Carrier Class Network changes Removal of T1/E1 where possible Core changes to ROADM, OTN, MPLS-TP Migrate over time to remove SDH/SONET RRH 3G 4G RF Over Fiber RRH RRH 2G 3G Base Station RF Node B T1/E1 Business Connection T1/E1 T1/E1 TDM (SDH/SONET) Legacy haul network Ethernet Carrier Class Ethernet over OTN T1/E1 T1/E1 SDH/ SONET Central Office ROADM Core SDH / Network SONET / with MPLS- ATM Core TP or PBB- Network TE over OTN Interfaces T1/E1 SDH/SONET Ethernet Next Gen haul network 4 4 Copyright ANRISTU

5 Network-Segmentation SAN Core Core Router Mobile Fronthaul Microcell /Picocell 8G/10G FC 10GbE/40Gb (RRH) (Data Center) ROADM ROADM 40G / 100G CPRI Metro RF Over Glass (Fiber) (BTS/NB) OLT Ethernet Switch 10G OTN Internet TDM Transport Access OLT GE/10GbE (RNC/BSC) Femtocell GbE/10GbE FTTx, xdsl Mobile haul ONU 5 Copyright ANRISTU

6 RF Over Grass Fibre Challenges Mobile Network (BTS/NB) Microcell /Picocell Several network technologies are mixed, like PDH, SDH, Ethernet Microcell /Picocell Solution of complex maintenance ONU and operation management (RRH) GE PON ONU ONU Reduce CAPEX / OPEX by migration from Legacy to Ethernet TDM (E1/T1) GbE/10GbE Synchronize Ethernet networks OLT Microcell TDM DS1/DS3, E1/E2/E3 (RNC/BSC) Traffic growing continuously Focus to expand traffic Core capacity Router 10G OTN (1) Grow traffic Expand traffic capacity Improve traffic efficiency RODAM TDM Transponder (2) High quality Ethernet network Switch for added value service like VoLTE, SLA The latest high speed network 100G Ethernet / 100G OTN 400G or more (2017~) RODAM 40G / 100G Internet Microcell Micro wave SDH/SONET (1) The latest high speed network (100G Ethernet / 100G OTN) (2) Improve traffic efficiency by ODU-Xc Priority management and traffic engineering network Mobile haul 6 6 Copyright ANRISTU

7 OTN -ground OTN was designed at first for Submarine networks Quickly moved all the way to the Core Metro Access Operators able to implement better services, control & management Control customer traffic from the access point & across the network (single system single management) Greater insight to faults, quick repair & reduces maintenance issues Single management of all technologies Legacy and Replacement Contribution to reduce the power budget of each network line and Tx/Rx port 7 7 Copyright ANRISTU

8 OTN - ground ITU-T (G. 709) defines Optical Transport Network (OTN) as a group of Optical Network Elements (ONE), connected with an optical fiber to transport, multiplexing, switching, managing, monitor /control to provide optical channels with user/client data. Typical signals, transported via OTN: SONET/SDH Ethernet Fibre Channel (CPRI) Key functions of OTN: Mapping / Demapping of non-otn signals Multiplexing and Demultiplexing of OTN signals (OPU and ODU s) Forward Error Correction 8 8 Copyright ANRISTU

9 OTN - ground Chronological development SDH Good fault management, performance monitoring and protection mechanism Not suited for packet based traffic Provides a deterministic and connection-oriented network Ethernet/IP These are the Key Points for a Telecom Network Efficient and with low costs in comparison to SDH Provides a non-deterministic and connectionless network in order to achieve minimum overhead/management No fault management, performance monitoring or protection mechanism 9 9 Copyright ANRISTU

10 OTN ground Architecture Overhead Structure Functioning FEC Coding Gain OTN Bit Rates OTN - Mapping 11 Copyright ANRISTU

11 Architecture OTS Area between EDFA s and optical element OMS Area between two optical elements Och Area between two digital elements OTU Area between two digital elements ODU/OPU Area between edge to edge elements Overhead per Layer enables further Management (Fault location etc.) BEI of ODU Layer; indicates BIP-8 of a single connection (client) BDI of OTU Layer; more critical Optical Domain Operator or Customer Digital ADM Optical ADM Optical Amp Optical ADM Digital ADM Operator or Customer BDI (ward Defect Indication) BEI (ward Error Detection) BIP-8 (Bit Interleaved Parity-8) OTS OTS OMS OCh (Channel) OTU (Section) ODU (Path) OPU (Payload) Digital Domain Copyright ANRISTU

12 Mechanism- Signal Interaction Key for all What is the cause of an Error/Alarm What happens, if an Error/Alarm occurs E.g..: if LOF is detected, a BDI must be returned by networkelement If the cause of a BDI is known, the problem can quickly be solved If the level of an Error/Alarm is known, the nature and scale of the problem can be evaluated more easily Total Network or On Client side only Copyright ANRISTU

13 Overhead Structure OTN is based on a fixed Frame size and consists of three areas: Overhead section Payload section FEC (Forward Error Correction) section 1 Column No# Frame Alignment Signal OTU Overhead section MFAS SM GCC0 RES RES JC Row No# RES PM & TCM TCM ACT TCM6 TCM5 TCM4 FTFL TCM3 TCM2 TCM1 PM EXP GCC1 GCC2 APS/PCC RES RES RES PSI JC JC NJO PJO OPU Payload OTU FEC ODU Overhead section OPU Overhead OTN OH similar to SDH FAS and OTU similar RSOH ODU similar MSOH OPU similar Ho POH OPU Payload similar to C-4 Payload 14 Copyright ANRISTU

14 OTUk Overhead Column Nr.# OTU Overhead Section Frame Alignment Signal MFAS SM GCC0 RES Row Nr.# RES PM & TCM TCM ACT TCM6 TCM5 TCM4 FTFL TCM3 TCM2 TCM1 PM EXP GCC1 GCC2 APS/PCC RES PSI OPU Payload OTU FEC ODU Overhead Section OPU Overhead Frame Alignment Signal FAS (Frame Alignment Signal) MFAS (Multi Frame Alignment Signal) SM (Section Monitoring) TTI (Trail Trace Identifier) SAPI (Source Access Point Identifier) DAPI (Destination Access Point Identifier), BIP-8 (Bit Interleaved Parity-8), BEI/BIAE (ward Error Indication and ward Incoming Alignment Error), BDI (ward Defect Indication), IAE (Incoming Alignment Error), GCC (General Communication Channel), SM Section TTI SAPI DAPI Operator Specific BIP BEI/BIAE BDI IAE RES Copyright ANRISTU

15 ODUk Overhead Column Nr. # OTU Overhead section PM Section TTI BIP Row Nr. # RES Frame Alignment Signal PM & TCM TCM ACT MFAS SM GCC0 RES TCM6 TCM5 TCM4 FTFL TCM3 TCM2 TCM1 PM EXP GCC1 GCC2 APS/PCC RES ODU Overhead section PM (Path Monitoring), TTI (Trail Trace Identifier), BIP-8 (Bit Interleaved Parity-8), BDI (ward Defect Indication), BEI (ward Error indication), STAT (STATus bits), DMp (path Delay Measurement), TCM ACT (Activation/Deactivation), TCM (Tandem Connection Monitoring), TTI (Trail Trace Identifier), BIP-8 (Bit Interleaved Parity-8), BDI (ward Defect Indication), BEI/BIAE (ward Error Indication and backward Incoming Alignment Error), STAT (STATus bits), DMti (Delay Measurement TCMi i=1 to 6) FTFL (Fault Type and Fault Location), EXP (Experimental Overhead), GCC1 and GCC2 (General Communication Channels 1/2), APS/PCC (Automatic Protection Switching and Protection Communication Channel). PSI OPU Overhead SAPI OPU Payload DAPI Operator Specific TTIi SAPI DAPI Operator Specific TCMi Section BIP-8i BEIi/BIAEi PM & TCM BDIi OTU FEC STATi DMt DMt2 BEI DMt3 DMt4 BDI PM & TCM DMt5 DMt6 STAT DMp Copyright ANRISTU

16 OTN Functioning. OTU section has three areas FAS (Frame Alignment) and MFAS (Multi Frame Alignment) Shows the start of the frame and MFAS Section Monitoring Includes details for each section (between any two Switches) Source- and destination address Parity check ward Error Indication GCC0/1/2 (General Communication Channel) ODU section Includes details of the total path (often assignable to clients) Source- and destination address Parity check ward Error indication Delay measurement FTFL (Fault Type and Fault Location), to indicate fault-status und -location APS/PCC (Auto Protection Switching / Protection Communication Channel), Data may pass a different part of the network TCM (Tandem Connection Monitoring) Section, enables the monitoring of individual sections (various carrier) of an end to end network Copyright ANRISTU

17 OPU Overhead Column No# OTU Overhead section Frame Alignment Signal MFAS SM GCC0 RES RES JC Row No# RES PM & TCM TCM ACT TCM6 TCM5 TCM4 FTFL TCM3 TCM2 TCM1 PM EXP GCC1 GCC2 APS/PCC RES RES RES PSI JC JC NJO PJO OPU Payload OTU FEC ODU Overhead section OPU Overhead Controls various Client Signal Mappings into the Payload AMP (Asynchronous Mapping Process) BMP (Bit synchronous Mapping Process) GMP (Generic Mapping Procedure) Based on PT (Payload Type) Overhead bits will be adapted PSI (Payload Structure Identifier) PT (Payload Type) CSF (Client Signal Fail) JC (Justification Control) NJO (Negative Justification Opportunity) PJO (Positive Justification Opportunity) PSI & JC Section CSF PT Reserved JC RES Copyright ANRISTU

18 FEC Row No# Column No# OTU Overhead section FEC Parity check-bytes are calculated over the Information-Bytes 1 to 239 of each Frame Alignment Signal MFAS SM GCC0 RES RES JC Sub-Row PM & and TCM inserted in the Bytes 240 to 255 of the same Sub-Row. In total there RES TCM6 TCM5 TCM4 FTFL RES JC TCM ACT OPU Payload OTU FEC TCM3 TCM2 TCM1 PM EXP RES JC are 16 Sub-Rows. GCC1 GCC2 APS/PCC RES PSI NJO PJO ODU Overhead section OPU Overhead The theoretical efficiency of the error Correction are calculated based on occurrence of randomized errors Copyright ANRISTU

19 .OTN Functioning OPU section consists of two areas Overhead Includes Payload Structure Identifier (PSI) and Payload Type (PT), the Overhead in connection with Concatenation and Overhead (e.g. Justification Control und Opportunity Bits) for mapping of client data into OPUk Payload Payload Container to carry the client data FEC Improves the erroneous behaviour and for longer optical transmission path (use of Reed Solomon Codes; RS(255,239)) Bitrate expansion due to FEC-Algorithm by 7% Improves the SNR by up to 6,2 db Correction of up to 8 symbol error 20 Technology Overview 20 Copyright ANRISTU

20 OTN ground Architecture Overhead Structure Functioning FEC Coding Gain OTN Bit Rates OTN - Mapping 22 Copyright ANRISTU

21 OTN Bit Rates - OTU OTU is a physical interface in an OTN Network. ITU-T Recommendation G.709 Optical Transport Network (OTN) line rates: FEC Multiplierate Gbit/s Ideal Payload Payload- OTU Rate OTN Type Multiplier OTU1 255 / STM-16/OC-48, 1GFC/2GFC OTU1e 255 / GigE LAN OTU1f 255 / GFC OTU2 255 / STM-64/OC-192, 4GFC/8GFC OTU2e 255 / GigE (LAN) OTU2f 255 / GFC OTU3 255 / GigE, STM-256/OC-768 OTU3e1 255 / xODU2e OTU3e2 243 / xODU2e OTU GigE / OTU: Optical channel Transport Unit 23 Copyright ANRISTU

22 OTN 10 Gb/s Mappings Copyright ANRISTU

23 OTN 40Gb/s Mappings 3 26 Copyright ANRISTU

24 OTN 100Gb/s Mappings 4 27 Copyright ANRISTU

25 Recommended Test-Scenarios OTN-Layer BER Error/Alarm Pass-through-Mode (OH-Overwrite) FEC Analog-Method Digital-Method Client to Client (Based on RFC2544/Y.1564) 29 Copyright ANRISTU

26 OTN-Layer BER Error/Alarm Pass-Through-Mode ODU-Multiplexing FEC Analog-Method Digital-Method Client to Client (Based on RFC2544/Y.1564) 31 Copyright ANRISTU

27 OTN Network Partition RFC2544/Y.1564 Test OTN-Layer Test BER Error/Alarm FEC 32 Copyright ANRISTU

28 Error/Alarm Status-check Monitoring of SM/PM 33 Copyright ANRISTU

29 BER-Analysis Investigation on various mappings in order to view the results based on Clientlevel E.g. BER at 1GbE 34 Copyright ANRISTU

30 OTN-Frequency-Offset 35 Copyright ANRISTU

31 OH-Header Manipulation 36 Copyright ANRISTU

32 OTN-Error/Alarm-Injection 37 Copyright ANRISTU

33 Pass-Through-Mode; OH transparent/overwrite Bidirectional monitoring Evaluate if Network-Element shows the correct response to Error situation. (OTU-AIS ; SM-BDI ) ME 38 Copyright ANRISTU

34 ODU Multiplexing Simulation of various Client-Signals (Eth., CPRI etc.) Throughput BER 39 Copyright ANRISTU

35 OTN-Layer BER Error/Alarm Pass-Through-Mode ODU-Multiplexing FEC-Test Analog-Method Digital-Method Client to Client (Based on RFC2544/Y.1564) 40 Copyright ANRISTU

36 Analog Method Random Error generation by varying the SNR using an optical attenuator. Input Error Ratio is determined with FEC disabled With FEC enabled the Error-Correction-Efficiency can be obtained ME FEC Encoder ME FEC Error Addtition=Off Optical Attenuator 1.FEC=Off 2.FEC=On DUT FEC Decoder FEC Efficiency 41 Copyright ANRISTU

37 Digital Method Random Error injection based on Poisson-Distribution in accordance with ITU-T O.182 ME ME Random Error Addition = On DUT FEC=On FEC Decoder FEC Encoder FEC=On 42 Copyright ANRISTU

38 Digital Method Reproducible and accurate FEC-Error-Correction -Test: Error generation based on Poisson-Distribution in accordance with ITU-T O.182 Poor characteristic of Poisson-Distribution Good characteristic of Poisson-Distribution FEC Efficieny 43 Copyright ANRISTU

39 Digital Method Reproducible and accurate FEC-Error-Correction -Test: Error generation based on Poisson-Distribution in accordance with ITU-T O Copyright ANRISTU

40 OTN-Layer BER Error/Alarm Pass-Through-Mode ODU-Multiplexing FEC-Test Analog-Method Digital-Method Client to Client (Based on RFC2544/Y.1564) 45 Copyright ANRISTU

41 RFC2544 / Y.1564; Client to Client / Embedded RFC2544/Y.1564 Test RFC2544 / Y.1564 Test End to End RFC2544 / Y.1564 Test Embedded 46 Copyright ANRISTU

42 What does RFC2544 mean? The RFC2544 defines Test-Scenarios to benchmark and characterize the performance of Network-Equipment. Throughput; Latency ; Frame Loss Rate ; to Frames (Burstability / Fragmentation-Defragmentation) The Tests should be performed at a number of frame sizes at least five frame sizes should be tested for each test condition. Frame sizes: 64, 128, 256, 512, 1024, 1280, 1518 Furthermore the format for reporting the results is described. 47 Copyright ANRISTU

43 Test-Setup Tester Tester TX (RX) Tester RX (TX) 3. Tester DUT 1 (e.g. 1GbE) WAN DUT 2 (e.g. 1GbE) 48 Copyright ANRISTU

44 ITU-T Y.1564 Service Activation Test ITU-T Y.1564 completes the testing in two phases Service Configuration Test Confirm each individual service is configured correctly checking, CIR (Committed Information Rate), EIR (Excess Information Rate), FTD (Frame Transfer Delay), FDV (Frame Delay Variation), FLR (Frame Loss Ratio), CBS (Committed Burst Size), EBS (Excess Burst Size). Service Performance Test Transmits one or many Service Configuration Tests simultaneously at the CIR confirming all traffic is able to traverse the network under the full service load over time. 49 Copyright ANRISTU

45 Comparison of Y.1564 and RFC2544 Test-Methodology RFC 2544; common Defined for benchmarking Network-Equipment Only run a test at a time (no simultaneous verification) ITU-T Y.1564 RFC 2544 Designed for Service activation Devices performance Concurrent services Multiple services simultaneously One service at a time Simulates A realistic network One service in a network Testing time Short due to simultaneous test / Long due to serial nature of test service Test result Directly related to SLA requirements Link performance limit 50 Copyright ANRISTU

46 Comparison of Y.1564 and RFC2544 One doesn t replace the other they are designed for different tasks Y.1564 RFC 2544 Comment Designed for Element testing. Designed for Network testing. No Yes When testing a single component you should stress it and multiple frame sizes sequentially. Yes No When testing a network you should stress by generating multiple streams at the same time. Fast testing time. Yes No The testing time can be almost the same depending on the settings but if the full RFC is completed it is very long. Y.1564 can take longer but allows the user to select shorter measurement times if they wish. Settings work with SLA s. Works on a loaded network. Yes No Y.1564 settings can be configured based on customers SLA agreements. Yes No Both are able to work on active networks but RFC 2544 is designed to find the network limit while Y.1564 is designed to find the circuit limit. Incorrectly configured either will bring affect customer traffic. 51 Copyright ANRISTU

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