Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Transmission Systems and the Telephone Network Chapter 4 in Leon Skip in Chapter 3 Articles 3.8.7, (polynomial math for CRC codes) I will ask you do to the long division in mod-2 arithmetic that we did last time Skip in Chapter (SONET frame structure) 4.6 Signaling in POTS

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies B B C C A A B C A B C A MUX (a) (b) Trunk group Figure 4.1 Sharing of an expensive channel by multiplexing (MUX)

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies A C B f C f B f A f W W W (a) Individual signals occupy W Hz (b) Combined signal fits into channel bandwidth Figure 4.2 Frequency Division MUX (FDM)

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies (a) Each signal transmits 1 unit every 3T seconds (b) Combined signal transmits 1 unit every T seconds t A1A1 A2A2 t B1B1 B2B2 t C1C1 C2C2 3T3T 0T0T 6T6T 3T3T 0T0T 6T6T 3T3T 0T0T 6T6T t B1B1 C1C1 A2A2 C2C2 B2B2 A1A1 0T 1T 2T 3T 4T 5T 6T Figure 4.3 Time Division MUX (TDM)

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies MUX b1 2...b frame Figure 4.4 Standard T1 Carrier (TDM of 24 PCM voice channels) (1+24channels*8bits/channel)*8000 frames/sec = Mbps

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies North American Digital Hierarchy Primary Multiplex Eg. Digital Switch 30 chan PCM 4th order Multiplex x4 2nd order Multiplex x4 3rd order Multiplex x Mbps Mbps Mbps Mbps CEPT 1 CEPT 4 European Digital Hierarchy 28 M13 Multiplex M23 Multiplex x7 Primary Multiplex Eg. Digital Switch 24 chan PCM M12 Multiplex x4 1 DS Mbps DS Mbps DS MbpsDS Mbps Figure 4.5

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies t Figure 4.6

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Figure 4.7 (Optical fiber network for long distance carrier in 1998) could not be reproduced well enough for inclusion.

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Low-Speed Mapping Function Medium Speed Mapping Function High- Speed Mapping Function DS DS1 DS2 CEPT-1 CEPT ATM 150 Mbps STS-1 STS-3c OC-n Scrambler E/O Mbps High- Speed Mapping Function Mux STS-n Figure 4.8

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies MUX DEMUX MUX DEMUX MUX DEMUX (a) pre-SONET multiplexing remove tributary insert tributary ADM remove tributary insert tributary (b) SONET Add-Drop multiplexing Figure 4.9

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies a b c 3 ADMs physical loop net OC-3n Figure 4.10

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies a b c logical fully-connected net (a) a b c 3 ADMs connected in physical ring topology OC-3n (b) Figure 4.11

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies a b c d a b c d (a) Dual ring (b) Loop-around in response to fault Figure 4.12

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Inter-Office Rings Metro Ring Regional Ring Figure 4.13

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies STE: Section Terminating Equipment, e.g. a repeater LTE: Line Terminating Equipment, e.g. a STS-1 to STS-3 multiplexer PTE: Path Terminating Equipment, e.g. an STS-1 multiplexer optical section optical section optical section optical section line optical section line optical section line path optical section line path (a) (b) STS PT E LTE STE STS-1 Path STS Line Section Mux reg SONET Terminal STE LTE STS PT E SONET Terminal Figure 4.14

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies BBB 87B Information Payload 9 Rows 125  s Transport overhead 90 bytes Section Overhead 3 rows 6 rows Line Overhead Figure 4.15

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Pointer 87 columns 9 rows first column is path overhead Synchronous Payload Envelope frame k frame k+1 Pointer first octet last octet Figure 4.16

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies STS-1 Map STS-1 Byte Interleave STS-3 Incoming STS-1 Frames Synchronized New STS-1 Frames Figure 4.17

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies 1 2 m Optical MUX 1 2 m Optical deMUX 1 2. m Optical fiber Figure 4.18

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Figure 4.19 (Optical signal in a WDM system) could not be reproduced well enough for inclusion. Figure 4.19

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies (a) WDM chain network a b c d (b) WDM ring network a b c 3 ADMs Figure 4.20

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies User 1 Switch Link User n User n-1 (a) Network (b) Switch Control N N Connection of inputs to outputs Figure 4.21

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies N N 2  N-1 Figure 4.22

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies nxknxk nxknxk nxknxk nxknxk N/n x N/n kxnkxn 1 2 N/n N inputs N/n N outputs 1 2 k 2(N/n)nk + k (N/n) 2 crosspoints kxnkxn kxnkxn kxnkxn Figure 4.23

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies nxknxk nxknxk nxknxk N/n x N/n kxnkxn 1 N/n Desired input 1 j m N/n Desired output 1 2n-1 kxnkxn kxnkxn n-1 N/n x N/n n+1 N/n x N/n 2n-2 free pathfree path n-1 busy n-1 busy Figure 4.24

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies From TDM DeMUX To TDM MUX Read slots in permuted order Figure 4.25

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies nxknxk nxknxk nxknxk nxknxk N/n x N/n kxnkxn 1 2 N/n N inputs n input TDM frame with n slots output TDM frame with k slots Figure 4.26

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies nxknxk N/n x N/n kxnkxn N/n 1 2 k kxnkxn kxnkxn nxknxk 2 nxknxk N/n first slot kth slot first slot kth slot Figure 4.27

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies nxknxk nxknxk nxknxk nxknxk N/n x N/n Time-Shared Space Switch kxnkxn 1 2 N/n N inputs N/n N outputs TDM n slots kxnkxn kxnkxn kxnkxn TDM k slots TDM k slots TSI Stage Space Stage Figure 4.28

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies 2x3 3x D1D1 B1B1 A1A1 B2B2 A2A2 C1C1 D2D2 C2C2 B1B1 A1A1 C1C1 D1D1 A1A1 B1B1 C1C1 D1D1 A1A1 C1C1 B1B1 D1D1 Figure 4.29

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Figure 4.30

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Signal Source Signal Release Signal Destination Go Ahead Message Figure 4.31

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies (a) Routing in a typical metropolitan area (b) Routing between two LATAs LATA 1 LATA 2 net 1 net 2 A B C D Figure 4.32

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies local telephone office Distribution Frame Serving Area I/f Pedestal feeder cable Switch distribution cable Figure 4.33

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Original signal Hybrid transformer Received signal Echoed signal Receive pair Transmit pair Figure 4.34

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Local analog Local digital Digital trunks Local Switch Tie lines Foreign exchange Channel-switched traffic (digital leased lines) Circuit- switched traffic Digital cross-connect System Figure 4.35

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Physical SONET Topology using ADMs and DCCs Logical Topology Switches see this topology DCC Figure 4.36 ADM

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Basic Rate Interface (BRI): 2B+D Primary Rate Interface (PRI): 23B+D BRI PRI BRI PRI Circuit Switched Network Channel Switched Network Private Signaling Network Packet Switched Networks Figure 4.37

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies SPC Control Signaling Message Figure 4.39

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Switch Processor Office B Switch Office A Processor Signaling Modem Trunks Figure 4.39

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies STP SSP Transport Network Signaling Network SSP = Service switching point (signal to message) STP = Signal transfer point (message transfer) SCP = Service control point (processing) SCP Figure 4.40

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies SSP Transport Network External Database Signaling Network Intelligent Peripheral Figure 4.40

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Application Layer Transport Layer Network Layer Data Link Layer Physical Layer Presentation Layer Session Layer SCCP MTP Level 3 MTP Level 2 MTP Level 1 ISUPTCAPTUP Figure 4.42

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Fewer Trunks Many Lines Figure 4.43

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies N(t) t all trunks busy trunk # Figure 4.44

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies # trunks Blocking Probability offered load Figure 4.45

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Tandem Switch 2 Tandem Switch 1 B C A (b) Trunk group 10 Erlangs between each pair 90 Erlangs E F D B C A (a) E F D Figure 4.46

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Switch High Usage Route Tandem Switch Alternate Route Figure 4.47

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies High Usage Route B-E Tandem Switch 1 Alternate Routes for B-E, C-F High Usage Route C-F Switch A Switch B Switch C Switch E Switch D Switch F Tandem Switch 2 Figure 4.48

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies High Usage Route Alternate Routes Tandem Switch 3 Tandem Switch 1 Tandem Switch 2 Switch A Switch B Figure 4.49

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Carried Load Offered Load Network Capacity Figure 4.50

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies Figure 4.51

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies AC= authentication center BSS= base station subsystem EIR= equipment identity register HLR= home location register wireline terminal MSC PSTN BSS STP SS#7 HLR VLR EIR AC MSC= mobile switching center PSTN= public switched telephone network STP= signal transfer point VLR= visitor location register Figure 4.52

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies LAPD m radio RRM MM CM radio LAPD m RRM LAPD 64 kbps SCCP MTP Level 3 MTP Level 2 CM MM RRM 64 kbps LAPD RRM 64 kbps MTP Level 3 MTP Level 2 SCCP UmUm A bis A mobile station base transceiver station base station controller MSC Figure 4.53

Leon-Garcia & Widjaja: Communication Networks Copyright ©2000 The McGraw Hill Companies satellite motion (a) (b) Figure 4.54