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CONSYL Digital Carrier Systems Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 1 CONSYL Digital carrier standard T-carrier North America, Japan E-carrier Europe, Mexico, South America Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 2 CONSYL T1 carrier system PCM PCM PCM MUX DS-1 frame DEMUX PCM PCM Department of Computer Engineering, Kasetsart University PCM 204325 Introduction to Computer Communications and Networks 4/11/40 page 3 CONSYL DS-1 frame • each channel also refers as DS0 125 ms channel #1 channel #2 ....... channel #24 frame bit 8 bit 193 bits data rate = (24x8 +1 bit)/125 ms = 1.544 Mbps Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 4 CONSYL T - carrier DSI Two DS1C channels are multiplexed into a single 6.312 Mbps DS2 channel DS2 DS3 DS2 DS3 DS2 Two 1.544 Mbps DS1 channels are multiplexed into a single 3.152 Mbps DS1C channel DSI DSIC DSIC DS2 DS3 DS3 DS2 DS2 DS3 DS2 DS3 Seven DS2 channels are multiplexed into a single 44.736 Mbps DS3 channel Six DS3 channels are multiplexed into a single 274.176 Mbps DS4 channel DS4 Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 5 CONSYL E1-frame 125 ms = 32 time slots = 2.048 Mbps 0 1 2 16 frame synchronization 31 signaling channel 30 voice channel+2 control channel Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 6 CONSYL E - carrier Thirty 64 kbps channels are multiplexed to create one 2.048 Mbps E1 channel E1 E1 E2 Four E2 channels are multiplexed into a single 34.368 Mbps E3 channel E3 E2 E3 E4 E1 E2 E2 E3 E4 Four E4 channels are multiplexed into a single 565.148 Mbps E5 channel Department of Computer Engineering, Kasetsart University E1 Four E1 channels are multiplexed into a single 8.448 Mbps E2 channel E3 E4 E4 Four E3 channels are multiplexed into a single 139.264 Mbps E4 channel E5 204325 Introduction to Computer Communications and Networks 4/11/40 page 7 CONSYL Digital carrier comparison x31 x 4 E5 E1 x 4 E2 x 4 E3 x 4 E4 2.048 8.448 34.368 139.264 564.992 x24 x 4 T2 x 7 T3 x 6 T4 T1 1.544 6.312 44.736 274.176 64 x24 x 4 J2 x 5 J3 x 3 J4 J1 1.544 6.312 32.064 97.728 Europ e USA J5 397.200 x4 Japan Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 8 CONSYL PDH Digital tramsmission systems (T-carrier, E carrier) combine lower order multiplex stream to get higher bit rate Different streams have small differences in clock signals. Solve by adding justification bit PDH = Plesiochronous Digital Hierachy almost synchronous Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 9 CONSYL PDH deficiencies (I) Lack of flexibility impossible to identify a lower bit rate channel from the higher-order bit stream. Extraction of 2 Mbps channel from 140 Mbps channel 34 Mbps 140 M LTE 140 140 34 34 140 M LTE 8 Mbps 34 34 8 8 demux the high bit rate down to the lower level 2 Mbps 8 8 2 2 remux back into higher level for onward transmission Customer site Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 11 CONSYL PDH deficiencies (II) Lack of performance No standard for monitoring the performance of traffic channel No management channel Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 12 CONSYL PDH deficiencies (III) Lack of 慚id-Fibre meet undefined interface specification on the line side of a line transmission PDH SDH LTE G.703 interface non standard line code and optical levels Department of Computer Engineering, Kasetsart University standard Network Node Interface (NNI) functional integration of MUX and LTE 204325 Introduction to Computer Communications and Networks 4/11/40 page 13 CONSYL SDH & SONET What is SDH/SONET ? SONET = Synchronous Optical Network Standard interface developed for using in the public network multiplexing standard for optical fiber transmission refers to the system used within the U.S. and Canada SDH = Synchronous Digital Hierarchy international community term (ITU-T recommendtions) Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 14 CONSYL SDH goals Goals make it possible for different carrier to interwork unify the U.S., European and Japanese digital system Provide a way to multiplex multiple digital signal togethers provide support for operations, administration, and maintenace Characteristics use single master clock to synchronize Bit stream can be a added or extracted directly Basic transmission rate = 155.52 Mbps Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 15 CONSYL Signaling rates SONET SDH Bit rate (Mbps) STS-1/OC-1 STS-3/OC-3 STS-9/OC-9 STS-12/OC-12 STS-18/OC-18 STM-1 STM-3 STM-4 STM-6 51.84 155.52 466.56 622.08 933.12 STS-24/OC-24 STS-36/OC-36 STS-48/OC-48 STM-8 STM-12 STM-16 1244.16 1866.24 2488.32 STS = Synchronous Transport Signal OC = Optical Carrier STM = Synchronous Transport Module Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 16 CONSYL Synchronous Container PDH signal container 1.5 Mbps 2 Mbps 6 Mbps virtual container 1.5 Mbps 2 Mbps 6 Mbps Path overhead for monitoring抯 purpose Department of Computer Engineering, Kasetsart University Each PDH stream is carried in an appropiate container 204325 Introduction to Computer Communications and Networks 4/11/40 page 17 CONSYL Syncronization抯 techniques sample frame • phase offset in byte pointer data #1 POH #1 frame #1 frame #2 pointer data #2 POH #2 data #1 Department of Computer Engineering, Kasetsart University data #1 • directly access signal signal using pointer data #1 • data begins anywhere in frame data #2 204325 Introduction to Computer Communications and Networks 4/11/40 page 18 CONSYL SONET System consists of switches, mux and repeaters mux repeaters section mux section repeaters section mux section line line path Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 19 CONSYL SONET Basic Frame structure 1 frame = 810 bytes in 125 ms 1 2 3 4 5 6 7 8 9 STS-1/OC1 row/column mapping 87 bytes Overhead : SOH for system management information Payload 6 bytes 9 bytes 3 bytes 3 bytes SOH = Section Overhead LOH = Line Overhead TOH = Transport Overhead LOH Payload : user data TOH Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 20 CONSYL SDH Basic Frame structure 1 2 1 frame = 2430 bytes in 125 ms 3 4 5 6 7 8 row/column mapping STM-1 261 bytes Overhead : SOH for system management information (OAM) Payload 6 bytes 9 bytes 3 bytes 9 bytes 9 SOH = Section Overhead LOH = Line Overhead TOH = Transport Overhead LOH Payload : user data TOH Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 21 CONSYL STM-1 Frame 9 bytes 261 bytes SOH LOH SOH frame #2 Payload #1 Payload #2 Department of Computer Engineering, Kasetsart University Payload #1 Payload #1 Payload #1 pointer LOH POH #1 pointer POH #2 frame #1 Payload #2 204325 Introduction to Computer Communications and Networks 4/11/40 page 22 CONSYL SOH, LOH and POH transport overhead section overhead line overhead A1 B1 D1 H1 B2 D4 D7 D10 Z1 A2 E1 D2 H2 K1 D5 D8 D11 Z2 STS-1 information payload C1 F1 D3 H3 K2 D6 D9 D12 E2 3 columns J1 B3 C2 G1 F2 H4 Z3 Z4 Z5 9 rows 87 columns path overhead Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 23 CONSYL SDH mux scheme STM-1 PDH Tributaries x1 AUG AU-4 VC-4 C-4 140 Mbps x3 x3 TU-3 TUG-3 VC-3 x7 AU-3 VC-3 x7 Department of Computer Engineering, Kasetsart University 45 Mbps 34 Mbps x1 TUG-2 TU-2 VC-2 C-2 6 Mbps TU-12 VC-12 C-12 2 Mbps TU-11 VC-11 C-11 1.5 Mbps x3 SONET-specific Europe-specific Universal C-3 x4 204325 Introduction to Computer Communications and Networks 4/11/40 page 24 CONSYL SDH Elements TributaryUnit Unit Tributary Containers path overhead Virtual Containers TributaryUnit UnitGroup Group Tributary pointer Tributary Unit AdministrativeUnit Unit Administrative Administrative Unit Group section overhead STM-1 Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 25 CONSYL Containers mapping sample C2 mapping containers C-11 C-12 C-2 C-3 C-4 Department of Computer Engineering, Kasetsart University 17 18 19 20 21 22 23 24 25 26 27 28 29 30 #bytes 25 34 106 672 2340 fixed stuff 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 signaling fixed stuff alignment C-12 E1 capacity 1.600 2.176 6.784 48.384 149.760 204325 Introduction to Computer Communications and Networks 4/11/40 page 26 CONSYL Containers, VC & TU C-12 3 bytes 4 bytes C-2 9 bytes C-11 VC-11 VC-12 12 bytes VC-2 plus POH TU-11 TU-12 TU-2 plus pointer Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 27 CONSYL TU-X format 3 columns 125 ms TU-11 1 2 1 2 3 9 rows 27 bytes 27 1728 kbps 27 125 ms TU-12 1 2 9 rows 36 bytes 4 columns 36 1 2 3 4 2304 kbps 36 12 columns 125 ms 1 2 108 9 rows 1 2 3 108 bytes TU-2 6912 kbps 108 Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 28 CONSYL TUG-2 to VC-3 4xTU-11 3xTU-12 1xTU-2 9 bytes TUG-2 may be • 4xTU-11 • 3xTU-12 • 1xTU-2 12 bytes 12 bytes 12 bytes 9 bytes 12 bytes TUG-2 9 bytes 7xTUG2 VC-3 1 total 85 columns 84 POH Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 29 CONSYL AU-3 to AUG 1 30 59 1 87 J1 B3 C2 G1 F2 H4 Z3 Z4 Z5 1 J1 B3 H1 H2 H3 C2 G1 F2 H4 Z3 Z4 Z5 30 59 87 J1 B3 C2 G1 F2 H4 Z3 Z4 Z5 30 59 A 1 87 J1 B3 H1 H2 H3 C2 G1 F2 H4 Z3 Z4 Z5 ABCABCABC A B C AB C Department of Computer Engineering, Kasetsart University 30 59 B 87 1 J1 B3 C2 G1 F2 H4 Z3 Z4 Z5 30 1 30 J1 B3 H1 H2 H3 C2 G1 F2 H4 Z3 Z4 Z5 59 87 VC-3 plus 2 column fixed stuff 59 87 AU-3 C 3xAU-3 to AUG AB C 204325 Introduction to Computer Communications and Networks 4/11/40 page 30 CONSYL TUG-3 to VC-4 VC-3 9 TU-3 TUG-3 86 justification bytes TU-3 PTR C-3 85 3xTUG-3 fixed stuff VC-4 P O H total 260 columns Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 31 CONSYL High order mux STM-1 #1 MUX Nx9 Department of Computer Engineering, Kasetsart University STM-1 #N STM-1 #2 stream byte interleave Nx261 204325 Introduction to Computer Communications and Networks 4/11/40 page 32 CONSYL 1xOC3 and 3xoC1 OC3 = 3xOC1 OC3c = 1X155.52Mbps carriers a 155.52 Mbps carriers consisting of 3 separated OC3 carriers a data stream from single source of 155.52 Mbps Higher-order frames also exist (e.g. OC12c). The amount of actual user data in an OC3c stream is slighly higher thanin an OC-3 stream! Department of Computer Engineering, Kasetsart University 204325 Introduction to Computer Communications and Networks 4/11/40 page 33