Figure 4-1 ADPCM (adaptive differential pulse code modulation)

2 4 5 7 9 5 2 4 5 7Difference

Figure 4-2 Local exchange network

International Carriers

Interexchange Carriers

Internet Service Providers

Cellular Providers

Business PBX

Customer Premises Equipment

Residential Customer

Local Loop

LECs

Local Exchange Network

Figure 4-3 Virtual Private Network

Auckland

201

Paris

202

London

203

Johannesburg

205

New York

204

SMS

NCP

SMS

- IXC POP

SMS – Service Management SystemNCP – Network Control Point

Figure 4-4 Interoffice Signaling

Switch Switch

Loop Signaling

Interoffice Signaling

Figure 4-5 Call Setup and Transmission

Send dial tone

Receive and translate digits

Seize trunk

Disconnect

.

Translate digits

Seize trunk

Disconnect

Translate digits

Seize trunk

Disconnect

Receive digits

Ring phone

Disconnect

Phone answered

Hang up

Phone off hook

Call Setup

Communicating

Call termination

LEC Central Office

LEC Central Office

IXC Tandem

IXC Tandem

A C DB E F

Figure 4-6 Call setup using common channel signaling

Switch B’ is located at CO B

Switch E’ is located at CO E

LEC Central Office

LEC Central Office

IXC Tandem

IXC Tandem

A C DB E F

Switch E’Switch B’

Note: Voice path and signal path separate

STP

SCPDatabase

SSPSSP

Figure 4-7 SS7 Architecture

SCP

SSP

SSP

STPSTP

STPSTP

SSP = Service Switching Point

STP = Signal Transfer Point

SCP = Service Control Point

Signaling Links

SCP

Figure 4-8 SS7 Layers Compared with the OSI Reference Model

OA&M

NetworkService

Part

Signaling network_____________________________

Signaling Link_____________________________

Signaling data link

TCAP___________Presentation___________Session___________Transport

Network Applications

7 Application

____________6 Presentation____________5 Session____________4 Transport

____________

3 Network

____________2 Data Link____________1 Physical

ISDN Service

User Part ISUP

SSCP (Signaling Connection Control Part)

TCAP = Transaction Capabilities Application partOA&M = Operations, Administration & MaintenanceMTP = Message Transfer Part

SS7 LayerOSI Layer

MTP

4

3

2

1

Figure 4-9 A Digital Central Office

ALI DLI ATI RLIDTI

TDM TDM

Digital Phone

Analog Phone

FAX PBX

CPU

CPUCS

PS

MCC Test monitor

Line and Trunk Interfaces

ALI - Analog Line InterfaceDLI - Digital Line InterfaceATI - Analog Trunk InterfaceDTI - Digital Trunk InterfaceRLI - Remote Line Interface

TDM - Time Division MultiplexerCPU - Central Processing UnitPS - Program StoreCS - Call store

Switch Features

ACT - Automatic Coin TelephoneAMA - Automatic message accountingANI - Automatic Number IdentificationLIT- Line Insulation Test SystemLMS - Local Message Metering SystemMCC - Maintenance Control CenterTMS - Transmission Measuring SystemTTS - Trunk Testing System

Class 5 Switch Components

Remote Line Interface

Trunks to Other

COs

ISDN

Phones

Figure 4-10 An AIN (Advanced Intelligent Network)

STPSS7 Network

SCP

CO

SSP IP

CO Central OfficeSSP Service Switching PointSTP Signal Transfer PointSCP Service Control Point IP Intelligent Peripherals

Customer Systems

Figure 4-11 IXC Tandem Switch Architecture

IMT Intermachine trunk

DAL Dedicated access line

FEX Foreign exchange

FGA Feature group A

FGB Feature group B

FGD Feature group D

LEC = End Office

PBX

IMT

LATA

FGB (trunk side)

FEX

FGA (line side)

FGD

LEC LEC

LECLEC

DAL

Tandem Switch Tandem

Switch Phone

Operator Console

Figure 4-x An Intelligent Network

Figure 4-7 SDH/SONET Architecture

Figure 4-11 Common Channel Signaling

Figure 4-12 SS7 Network

Figure 4-1 Digitizing a Voice signal

Quantizing Noise

Figure 4-5 SONET/SDH Architecture

Protect Fiber Counter-clockwise

Primary Fiber Clockwise

SONET

Multiplexer

SONET

Multiplexer

DLC

Administrator

DLC

Administrator

Figure 4-6 Terminal Multiplexers and Add/Drop Multiplexers

Terminal Multiplexer

Add/Drop Multiplexer

High Speed

High Speed High Speed

Low Speed

Low Speed

DS-1 1.54 Mbps to

OC-3 155 Mbps

OC-48 2.5 Gbps

DS-1 1.54 Mbps to OC-12 622 Mbps

OC-48 2.5 Gbps

OC-48 2.5 Gbps

Figure 4-8 SS7 Layers Compared with the OSI Reference Model

Signaling network

Signaling Link

Signaling data link

TCAP

Presentation

Session

Transport

Network ApplicationsOSI Layers

Application

Presentation

Session

Transport

Network

Data Link

Physical

7

6

5

4

3

2

1

ISDN Service

User Part ISUP

SSCP (Signaling Connection Control Point)

OA&M

Network service partM

T

P

TCAP = Transaction Capabilities Application part

OA&M = Operations, Adminiaration & Maintenance

MTP = Message Transfer Part