SDH Presentation-SDH Basics -Alcatel SDH Systems -Alcatel 1662SMC Introduction -SDH Link No.17 SDH Basics What are SDH & PDH ? Advantages of SDH over PDH. SDH Data rates. SDH Multiplexing Structure. SDH Basic Frame Structure. SYNCHRONOUS DIGITAL HIERARCHY SDH Basics What are SDH & PDH ? SDH stands for Synchronous Digital Hiararchy.In SDH each and every signal is synchronized exactly to the single (container) defined for that particular signal ( like C11,C12,etc).The techniques like bit stuffing and bit justification are adopted in SDH to achieve the synchronization. The signal used for SDH transmission is known as Synchronous Transport Module (STM). The various STM rates are illustrated below STM-1 (155.52 Mbps) STM-4 (622.08 Mbps) STM-16 (2488.32 Mbps) STM-64 (9953.28 Mbps) STM-256 (39813.12 Mbps) STM-1 STM-1 SDH STM-1 MUX STM-1 STM- 4 STM- 4 STM- 4 STM- 4 SDH MUX STM- 16 STM- 16 SDH STM- 16 MUX STM- 16 STM- 64 STM- 64 SDH STM- 64 MUX STM- 64 STM- 256 PLESIOCHRONOUS DIGITAL HIERARCHY . because the digital signals being multiplexed together are not at quite the same frequency .PDH (Plesiochronous Digital Hierarchy) Plesio means = similar Chronous means= Timing Plesiochronous ± ³almost synchronous´. etc.367990Mbps) E3(34.) but with slight timing differences as shown below.367998Mbps) E3(34.T1.367989Mbps) E3(34.E3.SDH Basics What are SDH & PDH ? (continues«) PDH stands for Pleisynchronuous Digital Hiararchy.447989 Mbps) E2(8.048001 Mbps) E1(2.048000 Mps) PDH MUX E2(8.447997 Mbps) E2(8.448000 Mbps) PDH MUX E3(34.047990 Mbps) E1(2.048 Mbps [32 x 64 kbps (DS0)] E2 ± 8.368 Mbps [4 x E2] E4 ± 139. E1 ± 2.The PDH contains the signals having similar data rate signals (like E1.264 Mbps [4 x E3] E1(2.447991 Mbps) E2(8.T2.E 2.448 Mbps [4 x E1] E3 ± 34.368000Mbps) PDH MUX E4(139.047992 Mbps) E1(2.264000Mbps) . It is also able to handle more recent services such as video on demand and digital video broadcasting via ATM. leased lines can be switched in a matter of minutes.mobile radio.SDH Basics Advantages of SDH over PDH High Transmission Rates: The highest data rate that can be achieved with PDH technologies is 140 mbps. low bit rate channels can be easily extracted from and inserted into the high-speed bit streams in SDH. etc. Integrated Services: SDH is the ideal platform for a wide range of services including POTS. WAN. It is now no longer necessary to apply the complex and costly procedure of demultiplexing then remultiplexing the plesiosynchronous structure. For example. Reliability: Modern SDH networks include various automatic back-up circuit and repair mechanisms (like Automatic Protection Switching (APS) and Equipment Protection Switching (EPS) which are designed to cope with system faults and are monitored by management. ISDN. As a result. The network provider can use standardized network elements (NE) that can be controlled and monitored from a central location via a telecommunications management network (TMN) system. and data communications (LAN. failure of a link or an NE does not lead to failure of the entire network. whereas the transmission rates up to 10Gbps (STM-64) can be achieved with SDH technology. . High Availability and Capacity matching: With SDH.). Easy Add & Drop Functionality: Compared to the older PDH system. network providers can react quickly and easily to the requirements of their customers. . Compatibility of transmission and administrative signals between different vendor may give trouble. For Add/drop of individual channels from the higher order stream we have to disassemble / reassemble it Redirection (cross-connection) of channels must be done by hand on DDFs. EOW and protection switching. Administrative connections require separate equipment to support Supervision.Disadvantages of PDH Changing from one hierarchical level to another requires additional equipment. SDH Basics SDH Data rates: STM-0 (51.08 Mbps) STM-16 (2488.52 Mbps) STM-4 (622.32 Mbps) STM-64 (9953. .28 Mbps) STM-256 (39813.84 Mbps) STM-1 (155.12 Mbps) Note: The STM-0 is not widely used in the telecom network except for some Microwave Links. 544Mbps) Or ATM(1.144Mbps) T-1(1.384Mbps) T-2(6.048Mbps) Or ATM(2.736Mbps) Or E-3(34.874Mbps) E-1(2.312Mbps) Or ATM(6.368Mbps) Or ATM(48.264Mbps) Or ATM(149.SDH Basics SDH Multiplexing Structure: STM-N xN AUG x1 AU-4 VC4 C4 x3 TUG-3 TU-3 VC3 E-4(139.6Mbps) x1 TUG-2 Containers Virtual Containers (Containers + POH) Tributary Units/Administrative Units (Virtual Containers + Pointers) Tributary Unit Groups/Administrative Unit Groups (Multiplexed structures of lower signals) TU-2 VC2 C2 x3 TU-12 VC12 C12 x4 TU-11 VC11 C11 Alignment Multiplexing .760Mbps) x7 STM-0 AU-3 VC3 C3 T-3(44. SDH Multiplexing Structure: KLM DETAILS K-TUG 3 L-TUG 2 M-TU 12 First KLM combination is 1 1 1 Last KLM combination is 3 7 3 Mapping of 63 E1s into STM1 E1 = 32 bytes/frame C12 = 34 bytes/frame (E1 +2 stuffed bytes) VC12 = 35 bytes/frame (C12 + 1 POH byte ) TU12 = 36 bytes/frame (VC12 +1 pointer byte) M So. . one TU12 occupies 4 columns(36 bytes) in an STM1 frame L TUG-2 = 3 X TU12 = 12 columns /frame TUG-3 = 7 X TUG-2 = 86 columns /frame K (7 X 12 + 2 stuffed columns are added) VC4 = 3 X TUG-3 = 261 columns /frame (3 X TUG-3 + 2 stuffed columns + 1 POH) STM1 = VC4 + SOH = 261+ 9 = 270 columns /frame. 4 AUG=1*AU-4 or 3*AU-3 .Tributary unit Group TUG-k=m*TU-n.2.3 n=11.where Poh is path over head Pathover head contain Payload content 3. 5. where C=Container.Virtual container VCn.2.Tributary unit TUn=VCn+PTR n=11.It is made up of Cn and Poh Vcn=Cn+Poh.the Tug-2/Tug-3 can consist of several types of capacity payloads with different sizes.1.3 lower oder VCn Where Pointer is an addittional rate used to locate its Vcn with in the TU 4. 2.12.Container Cn.3.2.it is made up of higher order VCn(n=3.4) and a pointer AUn=VCn+PTR n=3.n=Index of the container(n=11.Adminitrative Unit(AU).12. where k=2.12.3 TUG .4) The rate of the container depends on the signal which is transported. 9 bytes Payload :.Regenerator Section Overhead (27 bytes ) MSOH :± Multiplexer Section Overhead (45 bytes) Total Section Overhead (SOH) :± RSOH + MSOH AU-4 Pointer :.52 Mbps . RSOH :.261 x 9 = 2349 bytes STM -1 Data rate = (270 x 9) bytes = 2430 bytes = 2430 x 64 kbps = 155520 kbps = 155.SDH Basics SDH Basic Frame Structure (STM-1): 270 Colomns 1 1 9 10 270 RSOH (3 x 9 Cells) 3 9 Rows 4 5 AU-4 POINTER PAYLOAD (261 x 9 Cells ) MSOH (4 x 9 Cells) 9 Each cell represents a single byte indicating a 64 kbps channel. ): Section Overhead (SOH ) A1 B1 D1 A1 A1 A2 E1 D2 A2 A2 J0 F1 D3 X X * * B2 * * B2 * * AU-4 Pointer B2 D4 D7 D10 S1 K1 D5 D8 D11 M1 K2 D6 D9 D12 E2 X X X ± Bytes Reserved for national use.SDH Basics SDH Basic Frame Structure (STM-1) (Continues«. * .Media Dependant Bytes . .D3 D4.E2 F1 J0 K1.B2 D1. parity bytes Qecc Network Management Qecc Network Management Voice Connections Maintenance Trace Identifier Functions Automatic Protection Switching (APS) Control Clock Quality Indicator Transmission Error Acknowledgement .D2.K2 S1 M1 Frame Alignment Quality Monitoring .«««.A2 B1.D12 E1..SDH Basics SDH Basic Frame Structure (STM-1) (Continues«.): Overhead Bytes Functions Overhead Byte A1. Alcatel SDH Systems Alcatel SDH Systems 1662SMC 1642 1660SM Version 1(R1) Version 2(R2) Supports Upto STM-1 Version 4(R4) Version 5(R5) Supports Upto STM-4 Supports Upto STM-16 Supports Upto STM-16 Supports Upto STM-64 . Alcatel 1662 SMC Introduction Features Shelf View Commonly used cards Technical Specifications . network rings and meshed networks.707. Compatible with existing plesiochronous systems as well as with the installed SDH networks. Equipment (EPS) and network (MSP) protection mechanism Matrix capacity 96*96 stm-1 equivalent matrix(HO) 64*64 stm-1 equivalent matrix(LO) Network interfaces: Stm-1/4/16 Customer interfaces: 2Mbps.34/45Mbps. The 1662SMC is transmission equipment operating at 155.140Mbps.080 Mbit/s (STM-4) and 2488.gigaethernet . 622.520 Mbit/s (STM-1) . It can be configured as a Multiple Line Terminal Multiplexers or as a Add/Drop Multiplexers or as a Mini local cross-connect for applications in linear links.320 Mbit/s(STM-16).Alcatel 1662 SMC Introduction Features: It complies with the Synchronous Digital Hierarchy (SDH) defined in ITU-T Recommendation G.ethernet. ALCATEL SDH LINK-17 PONDY TO TRICHY: STM 4 LINK 26km 49km 65km PONDICHERRY CUDDALORE CHIDAMBARAM KUMBAKONAM TANJORE 50km 54km TRICHY Total Pondy ± Trichy Fiber Owner : 244 KMS : BTSOL Fiber allotted for vsnl/Ttsl : F no 39 ± F no 48 Fiber used for SDH Link name & no : F no 43&44 : SDH LINK No 17 . Port(Basic area)Area: Slot 6-15 (Hosts Port Cards like SYNTH. . P4S1.etc). . P63E1. A4S1. Sergi .Access Area 1: Slot 1-5 ( Hosts Access Cards like A63E1. .Access Area 2: Slot 16-20 ( Hosts Access Cards like A63E1. etc).Total Slots : 20 .etc). Congi . A4S1.Alcatel 1662 SMC Introduction Shelf View: ACCESS AREA-1 PORT AREA ACCESSAREA-2 . It consists the Optical module it is named as IL. It consists of power supply&house keeping unit.2.4. 63 E1 indcates Electical signals. There are two synth cards its inserted in slot no 6&15. 6. 5. LSPORT/HSPROT: Its is a Low Speed/High speed protection Card.1.A indicates access area.these are called Optical modules.2. 3.(i.These cards receive the signal coming from the access card via back panel. P63E1 card : P indicates port. Congi card : It the used to control the whole SDH system. P4S1N card: P indicates Port . card 4. It is used to implement EPS protection. .e)it implements the connection between the access and spare card.IS1.. the congi card is in slot no1 2.IL-1. A63E1-120 : it¶s a card corresponding to P63E1 card. Synth4Card: It is card used to insert the optical signals from the fms.CARDS USED IN THE ALCATEL SDH LINK-17 1.S1N indicates STM1. Synth card in slot no:6.15 . Congi card in Slot no.1 5. Note: 1. Inserting a port card we have to insert a corresponding acess card in the particular slot. 9. IL. 2.7. Port area Slot No-7 : No-2 Slot No-8 : No-3 Slot No-9 : No-4 Slot No-10 : No-5 Slot No-11 : No-16 Slot No-12 : No-17 Slot No-13 : No-18 Slot No-14 : No-19 4.SERGI CARD: Used as a stand by card for the CONGI CARD 8. Sergi card in Slot no-20 6. For All cards corresponding stand by cards are used.It indicates SHORT HAL . IS.It indicates LONG HAL it should in corresponding SYNTH CARD. : Corresponding Acess area 3. 12.10.11.12.8.9.11.10. P3E3T3 Prt card is a bi-directional interface from/to three PDH streams at 34Mbits/s or at 45Mbits/s Switchable and the STM-4 (1) Multicolor LED: Red led .13.8. in service unit Orange led .12.It is one of the board that can be EPS protected. local unit alarm Green led .13.9.13.14 P63E1 processes 63 2Mbits/s signals whose accesses are on the relevant Access cards A21E1.10.A63E1 P4ES1N handles four electrical STM-1 Signals.9.All four accesses are on the relevant access card(A4ES1). unit in stand-by (EPS schema) .8.Alcatel 1662 SMC Introduction Commonly Used Cards: ACRONYM P63E1N P4ES1N P3E3T3 SLOTS 7.14 7.11.14 7. B.12.9.) (3) Bicolor LED: Red led .All the four accesses are on the Relevant Access card(A4ES1).14 P4ES1N handles four electrical STM-1 signals.8. P4E4N it describes the same features of P4S1N.11.10.12.13. Two STM-1 electrical modules(Electricl or optical )can be hosted on the board.13.11.It can be EPS protected.8.) (2) Channel #2 (N.14 7. in service unit .Alcatel 1662 SMC Introduction Commonly Used Cards ( continues.10.B..9. Two further STM-1 modules can be hosted on the Access card A2S1 LEGEND: (1) Channel #1 (N.): ACRONYM P4ES1N P4E4N SLOTS 7. local unit alarm Green led . e)congi-A and congi-B CONGI-A hold the Equip MAC(media access control) address LEGEND: (1) Power (2) Housekeeping and remote alarm (3) Rack lamp (not used in slot 20) (4) QMD Q2 (not used in slot 20) (5) I/O BNC Q3 10base2 (not used in slot 20) (6) RJ45 Q3 10baseT (not used in slot 20) (7) Bicolor LED: Red led ..): ACRONYM CONGI SLOTS 1. in service unit .Alcatel 1662 SMC Introduction Commonly Used Cards ( continues. 20 1662SM-C houses two congi card(i. local unit alarm Green led . B.1) (6) L1-L2 LEDs status for selective and multiple call (N.703 2 channels RS232 2 channels V. 2Mbit/s Input channel J3 . in service unit . local unit alarm Green led .I/p o/p clock interface for NE synchronization LEGEND: (1) Power (2) Auxiliary channels: 2 channels G..Alcatel Used Cards ( continues.B. 2MHz output (T4) or 2Mbit/s output (T5) J4 . 2MHz Input (T3) or 2Mbit/s Input (T6) J2 .2) (7) Telephone jack (8) Line seizure Key (9) EOW zone selection Key (10) Reset command Key (11) Bicolor LED: Red led . 2Mbit/s J1 .11 (3) Aux and Sync. 2Mbit/s output channel (4) Four wire telephone extersion point (RJ11) (5) Z1-Z4 EOW zone selection LEDs (N.Auxillary interface.): Introduction 1662 SMC Commonly ACRONYM SERGI SLOTS 20 Sergi card Provides reduced combination of congi and service card functions It has Power interface. Not Urgent Alarm (Minor) (7) Yellow LED .Equip controller. Indicative Alarm (Warning) (10) Green LED . It is also called as Compact ADM16 Card LEGEND (1) Reset command key (2) Channel #1 (N. Urgent Alarm (Critical or Major) (6) Red LED . local unit alarm (INT) Green led . Abnormal condition (9) Yellow LED . in service unit (12) Alarm storing pushbutton (Attended) . Alarm storing (Attended) (8) Yellow LED .. Performance monitoring collection.remote inventory Synth 16 cards have a 96*96 stm-1 Matrix capacity. when on it means active unit when off it means standby unit (11) Bicolor LED: Red led .) (3) Lamp test pushbutton (4) Personal Computer Connector (F interface) (5) Red LED .): ACRONYM SLOTS SYNTH16 6.Alcatel 1662 SMC Introduction Commonly Used Cards ( continues.15 SYNTH16 can be EPS 1+1 Protected Slot no:6 is main card Slot no:15 is spare card Synth16 card is equipped with two parts for modules 1*STM-16 signals can be processed by the SYNTH 16 card Synth 16 card performs several fns like shelf controller.B. 18.5.4.19 A63E1 is the access card for the P63E1 63*2Mbit/s Access card(A63E1)Provides the connections from backpanel to the external line and vice versa for the 63 PDH signals..Alcatel 1662 SMC Introduction Commonly Used Cards ( continues. Three different type of connectors available: A63E1/A:75 ohms unbalanced A63E1/B:120 ohms balanced A63E1/C:75 Ohms unbalanced with coax(3 slot wide) LEGEND (1) Channel #1-7 (2) Channel #8-14 (3) Channel #15-21 (4) Channel #22-28 (5) Channel #29-35 (6) Channel #36-42 (7) Channel #43-49 (8) Channel #50-56 (9) Channel #57-63 .17.3.): ACRONYM A63E1B (120Ohm) SLOTS 2.16. B. in service unit . local unit alarm Green led ..) (2) Channel #4 (N. LEGEND (1) Channel #3 (N.Alcatel 1662 SMC Introduction Commonly Used Cards ( continues.16.): ACRONYM A2S1 SLOTS 2.4. A2S1 can host upto 2modules(optical stm-1) in the front panel.5.19 A2S1 is the access card for the P4S1N and P4E4N port cards.3.) (3) Bicolor LED: Red led .17.B.18. 4.3.5.18.19 A3E3 Provides 3*34Mbit/s accesses for the P3E3T3 A3T3 Provides 3*45Mbit/s accesses for the P3E3T3 For each P3E3T3 One A3E3.19 2.5.4.16.Alcatel 1662 SMC Introduction Commonly Used Cards ( continues.17.A3T3 is necessary LEGEND (1) Channel #1 (2) Channel #2 (3) Channel #3 (4) Bicolor LED: Red led .3.18.16.): ACRONYM A3E3 A3T3 SLOTS 2.. local unit alarm Green led . in service unit .17. 18.16.19 A4ES1 Provides 4 STM-1 Accesses for the P4ES1N.17. in service unit .. local unit alarm Green led .Alcatel 1662 SMC Introduction Commonly Used Cards ( continues. For each P4ES1N one A4ES1 is Necessary LEGENDA (1) Channel #1 (2) Channel #2 (3) Channel #3 (4) Channel #4 (5) Bicolor LED: Red led .5.): ACRONYM A4ES1 SLOTS 2.4.3. A2S1 SYNTH4 S-1.): MODULE ACRONYM S-1.P4ES1 ATM4X4. .1 L-1.2 EQUIPED ON PORTS P4S1N.1 L-1.1 S-Stands for short haul 1-stands for stm-1 1-stands for representing 1310nm L-1.1 L-Stands for Long haul 1-stands for stm-1 1-stands for representing 1310nm Module types: Stm-1 and stm-4 Optical module:SC-PC Type and Fc-Pc Type are available Stm-1 & stm-4 Optical modules are available and it physically different 140Mbit/s-STM-1 Electrical module..Alcatel 1662 SMC Introduction Commonly Used Cards ( continues. Alcatel 1662 SMC Introduction Commonly Used Cards ( continues. temperature major than 55° C Green led ..): LEGENDA (1) Multicolor LED: Red led . in service unit (2) Battery A connector (3) Battery B connector (4) Alarms connector for 1662SMC on the Left side of the Rack (5) Not used (6) Alarms connector for 1662SMC on the Right side of the Rack (6) . local unit alarm Orange led . PSC front view HWF + VBATT (male) GND (female) POWER -VBATT (male) . 1 (long haul) L.1 STM.1.16 OPTICAL INTERFACE S.Doing so may result in the permanent damage to the eyesight.1.1.1 (short haul) L.1 (long haul) L.4 STM.4.1 STM.1 (short haul) L.Alcatel 1662 SMC Introduction Technical Specifications: Safty First The optical interfaces which have HAZARD LEVEL 3A (see Table A below ) carry the following hazard symbol label: Caution : Invisible Laser Radiation may be present inside the optical interfaces carrying the above label .4.4 STM.16 STM.4.2 (long haul) S.2 (long haul) S.1 STM.16 STM.1 (short haul) L.4.1 (long haul) L.hence NEVER directly view into the beam.4.4.4 STM.2 (long haul) HAZARD LEVEL 1 3A 3A 1 3A 3A 3A 3A 3A . UNIT/PORT STM. Transmission Alarms 4.CLASSIFICATION OF ALARMS SEVERITY ALARMS SYNTHESIS 1.Equipment Alarms MANAGEMENT ALARMS SYNTHESIS 1.Major Alarms 3.Minor Alarms 4.External points(House keeping Alarms) 3.Critical Alarms 2.Local access 4.Operating system 5.Abnormal condition .Warning Alarms 5.Intermediate Alarms DOMAIN ALARMS SYNTHESIS 1.Supervision 2.Alignment 3.Synchronization Alarms 2.Managed by Nm & RM 6. OTDR (Optical Time Domain Reflectometer) and OSA (Optical Spectrum Analyser) . Power -48V DC. power meter. humidity and dust control Fire safety by centralised monitoring and automatic operation of extinguisher LCT access through Q interface for NMS access through the LAN card Tools: Power source. 6A MCB Rating used in the TRU unit is 16A The max current consumed by the Equipment is less than 4Amps A/C environment with temperature. of tributaries Line Code P4S1E Bit rate Line Code P4E4 Bit rate Line Code . of channels Line Code Signal amplitude 2048 Kbit/s ±50 ppm 63 HDB3 2.Alcatel 1662 SMC Introduction Technical Specifications (Continues«): Interface P63E1 Charaterisitics Bit rate No.37 Vp on 75 Ohm unbalance/ 3 Vp on 120 Ohm balance.736 Kbit/s ± 20ppm 3 B3ZS 155 520 Kbit/s ± 20 ppm CMI 139264 Kbit/s ±15 ppm CMI Electrical Interface Characteristics- P3E3 Bit Rate No. 34368 Kbit/s ±20 ppm 3 HDB3 1Vp/75ohms 44. of tributaries Line Code Signal amplitude P3T3 Bit rate No. 5dB -37dB -10dB L 1.Alcatel 1662 SMC Introduction Technical Specifications (Continues«): Optical Characteristics ± STM-1 Trans Power Receiver Sensitivity Receiver Overload Optical Connectors STM-4 Trans Power Receiver Sensitivity Receiver Overload Optical Connectors STM-16 Trans Power Receiver Sensitivity Receiver Overload S 1.1 -15 to -8dB -28dB -8dB FCPC/SCPC S 16.1 2 to -3dB -28dB -8dB L 4.2 0 to 5dB -37dB -10dB .2 2 to 3dB -28dB -8dB L 1.1 0 to -5dB -18dB 0dB L 16.1 -15 to -8dB -28dB -8dB FCPC/SCPC S 4.1 0 to .1 2 to -2dB -27dB -8dB L 16.2 2 to 2dB -28dB -8dB L 4. therefore the mating cable needs to terminate in a DB9/F (Female pin) connector .RS232 Pin Assignments (DB9 PC signal set) Pin 1 Received Line Signal Detector (Data Carrier Detect) Pin 2 Received Data Pin 3 Transmit Data Pin 4 Data Terminal Ready Pin 5 Signal Ground Pin 6 Data Set Ready Pin 7 Request To Send Pin 8 Clear To Send Pin 9 Ring Indicator The connector on the PC has male pins. PROTECTION TYPES EPS Equipment Protection Switching MSP Multiplex Section Protection 1:1 1:N MSP-LINEAR MS-SP RING SNCP/N SNCP/I EPS:Protection against the equipment failure MSP:Protection against the equipment failure And the Line Failure . The mode of 1+1 EPS Protection is Non Revertive.The 1+1 EPS Protection type means that one working equip is Protected by One Redundant Equip 2. .EPS(Equipment Protection Switching) 1+1 Type EQUIPMENT 1 EQUIPMENT 2 1. EPS(Equipment Protection Switching) 1:N Type LINE 1 EQUIPMENT 1 LINE 2 EQUIPMENT 1 LINE N EQUIPMENT N EQUIPMENT P 1)1:N Type protection means that N working Pieces of equip are protected by just 1 Portecting Equivalent. 2)The mode of 1:N Eps protection is revertive. . MSP(Multiplex Section Protection) MSP(linear) is also called as APS(Automatic Protection Switching) NE-A NE-B WORKING TX PROTECTION 1+1Protection RX 1:1Protection HIGH PRIORITY LINE WORKING TX LOW PRIORITY LINE WORKING RX RX TX TX TX WORKING WORKING PROTECTION RX RX 1:N Protection .
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