163
Copyright © 2005 Heathkit Company, Inc. All rights reserved. Unit 9 Buses, Video, and Upgrades

Buses, Video, and Upgrades - University of Kentuckyakali2/TB143/Lecture9.pdf · 2008. 9. 25. · 11 Industry Standard Architecture (ISA) Bus •Introduced on the IBM AT Computer •16-bit

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  • Copyright © 2005 Heathkit Company, Inc. All rights reserved.

    Unit 9

    Buses, Video, and

    Upgrades

  • 2

    CPUCPU

    MemoryMemoryKeyboard ControllerKeyboard Controller

    Parallel Port

    System Controller

    Adapter

    Video

    Adapter The Data BusThe Data Bus

  • 3

    Keyboard ControllerKeyboard Controller

    System Controller

    Adapter

    Video

    Adapter

    CPU

    MemoryMemory

  • 4

    MemoryMemory

    Adapter

    Video

    Adapter

    CPU

  • 5

  • Copyright © 2005 Heathkit Company, Inc. All rights reserved.

    Expansion Buses

  • 7

    What is a Bus?

    • Signal Pathways

    • A way of passing information between components inside and outside the computer.

    • A modular way of expanding the functions or capabilities of the computer.

  • 8

    PC Bus Architectures• ISA

    • MCA

    • EISA

    • VL-Bus

    • PCI

    • AGP

    • PCI Express

    • PC Card

  • 9

    The Original IBM PC Bus

    • Introduced on the original IBM PC

    • 8- bit data path

    • 4.77-MHz clock

    • 8 Interrupts - Only one of which was available for expansion boards.

    • 4 DMA Channels - Only one of which was available for expansion boards.

  • 10

    8-Bit Card

    8-Bit Slot

    The Original IBM PC Bus

  • 11

    Industry Standard

    Architecture (ISA) Bus• Introduced on the IBM AT Computer

    • 16-bit data path

    • Backward compatible with IBM-PC Bus

    • 8-MHz clock

    • 15 Interrupts

    • 7 DMA Channels

  • 12

    16 Bit Card16-Bit Card

    16-Bit Slot

    Industry Standard Architecture

    (ISA) Bus

    8-Bit Section Added Pins

  • 13

    16-Bit Slot

    Industry Standard Architecture

    (ISA) Bus

    8-Bit Card

  • 14

    Micro-Channel

    Architecture (MCA) Bus • Introduced on the IBM PS/2

    • 16-bit or 32-bit data path

    • 10-MHz clock

    • Configured by software rather than by jumpers or switches

    • Not compatible with the ISA bus

    • Bus Mastering

  • 15

    Bus Mastering• Allows data to be passed from one

    device to another without CPU

    intervention.

    • Allows a controller card to take

    control of the bus, leaving the CPU

    free to concentrate on other tasks.

  • 16

    Bus Mastering vs. DMA

    • DMA can send data from peripheral

    to RAM or from RAM to peripheral,

    without the intervention of the CPU.

    • Bus Mastering can send data from

    peripheral to peripheral, without the

    intervention of the CPU.

  • 17

    Extended ISA Bus (EISA)

    • The industry’s answer to the MCA bus

    • Backward compatible with ISA

    • 16-bit or 32-bit data path

    • 8-MHz Clock

    • Configured by software, not jumpers or

    switches

    • Bus Mastering

  • 18

    CPU

    BUS

    Controller

    BUS

    Controller

    ISA Bus

    Slots

    High Speed

    CPU Bus

    High Speed

    CPU Bus

    Low Speed

    I/O Bus

    Low Speed

    I/O Bus

  • 19

    CPU

    BUS

    Controller

    BUS

    Controller

    ISA Bus

    Slots

    Local Bus

    SlotsHigh Speed

    CPU Bus

    High Speed

    CPU Bus

    Low Speed

    I/O Bus

    Low Speed

    I/O Bus

  • 20

    VESA Local Bus (VL-Bus)

    • Clock speed same as the processor

    • 32-bit data path

    • Regular ISA slot with local bus

    connector added

    • Bus Mastering

  • 21

    Peripheral Component

    Interconnect (PCI)

    • Developed for Pentium-class processors

    • 32-bit and 64-bit data path versions

    • 33-MHz Clock

    • Processor Independent

    • Plug and Play with Bus Mastering

  • 22

    Peripheral Component

    Interconnect

    (PCI) Bus

  • 23

    Accelerated Graphics

    Port (AGP)

    • Developed for high speed graphics cards

    • Frees the PCI bus from making video transfers

    • Used only for video cards

    • Considered a port rather than a bus

    • 66 MHz, 32-Bit

  • 24

    Accelerated Graphics Port

    (AGP)

  • 25

    The PC Card

  • 26

    PC Card• Personal Computer Memory Card

    International Association (PCMCIA)

    • Originally designed for adding memory to portable computers

    • A universal bus that can accommodate any type of device

    • Can be used with desktop PCs with the proper adapter

    • “Hot Swapping” capability

  • 27

    What is the

    Universal Serial Bus?

  • 28

    Feature...

    • It’s an external expansion bus

    using cables (outside the PC).

    • Can daisy chain 127 peripherals

    to a port

  • 29

    Feature...

    • Plug-and-Play, hot-pluggable, automatic configuration

    • USB 1 provides 12 megabits/second data transfer rate

    • USB 2 provides 480 Mbps

    • USB peripherals can be powered by the USB bus (+5 volts DC).

  • 30

    Feature...

    • Standardized connectors

    • Five meter-long peripheral

    connections

  • 31

    Ordinary USB Peripherals

    • Cartridge, Tape, and Floppy Drives

    • Modems

    • Printers, Scanners

    • ISDN, T1 Interfaces (Network

    Applications)

    • Input devices such as Mice, Joysticks,

    Keyboards , Graphics Tablets

    • Multimedia Game Equipment

  • 32

    Not So Ordinary USB

    Peripherals• Digital Cameras

    • Digital Speakers

    • Video Monitors

    • Biometric Security Devices

    • Multi-User Games

    • Digital Audio Devices

  • 33

    More Not So Ordinary

    USB Peripherals

    • Hubs

    • CTI Devices

    • Telephony (PBX, Digital

    Telephones)

  • Copyright © 2005 Heathkit Company, Inc. All rights reserved.

    Video Systems

    and Monitors

  • 35

  • 36

  • 37

  • 38

  • 39

  • 40

    Horizontal

    Deflection

    Coils

  • 41

  • 42

  • 43

  • 44

  • 45

    Horizontal Scanning

    Frequency

    • The number of lines per second scanned by the monitor.

    • Varies from about 15 KHz to over 50 KHz.

    • A popular scan rate is 31.5 KHz.

    • At this rate, one horizontal line is scanned in 26.66 microseconds.

  • 46

    The Horizontal Scanning

    Frequency is determined

    by the Horizontal Sync

    Signal.

  • 47

    Vertical

    Deflection

    Coil

  • 48

    Vertical Retrace

  • 49

    Vertical Scanning Frequency

    (Refresh Rate)

    • The number of times per second that the whole screen is scanned.

    • Varies from about 50Hz to over 100Hz.

    • Popular vertical scan rates are 60Hz and 70Hz.

    • At 70Hz, the entire screen is painted in about 14.28 milliseconds.

  • 50

    The Vertical Scanning

    Frequency is determined

    by the Vertical Sync

    Signal.

  • 51

    The Screen Refresh Rate

    43 Hz

    60 Hz

    72 Hz

    75 Hz

  • 52

    Interlaced Mode

    60 Hz60 Hz

  • 53

    Different resolutions often use

    different scan frequencies.

    • 640x480 31.5KHz 60Hz

    • 800x600 37.8KHz 72Hz

    • 1024x768 35.5KHz 87Hz

    Resolution Horizontal Freq. Vertical Freq.

  • 54

    The Screen Resolution

    Resolution Colors

    320 x 200 4, 256

    640 x 200 2

    640 x 350 16

    640 x 480 16, 256, 32K, 64K, 16 Million

    800 x 600 256, 32K, 64K, 16 Million

    1024 x 768 256, 32K, 64K, 16 Million

    1280 x 1024 256, 32K, 64K, 16 Million

  • 55

    Resolution vs. Monitor Size

    Monitor Size

    13-inch

    14-inch

    15-inch

    17-inch

    21-inch

    Max Useful Resolution

    640 x 480

    800 x 600

    800 x 600

    1024 x 768

    1600 x 1200

  • 56

    Measuring Screen size

    Screen size is measured diagonally.

  • 57

    Aspect Ratio =

    Horizontal Size

    Ver

    tica

    l S

    ize

    Horizontal Size

    Vertical Size

  • 58

    The LCD Display

    • The LCD is the second most common type of display technology.

    • LCDs offer several advantages:

    – Flat display area

    – Low power

    – Larger viewable area

  • 59

    • Generally more expensive than

    comparable CRT display.

    • Resolutions can be less than a

    comparable CRT.

    • LCD displays do not:

    – Emit electromagnetic radiation

    – Have high voltages present in the

    chassis.

    Advantages

  • 60

    • Available for both

    desktop and notebook.

    • Two common LCD

    technologies:

    – Active-Matrix Analog is

    common on smaller low

    cost displays

    – Active-Matrix Digital is

    used in larger high-end

    displays.

  • 61

    • LCDs use a unique material called liquid crystal.

    • Liquid Crystal has properties similar to water and crystal.

    • By applying a voltage, the amount of light can be controlled.

    • Color LCDs use color filters to create the color display.

  • 62

    Transparent Glass

    Plate

    Liquid Crystal Molecules

    Transparent

    Electrode

  • 63

    • Components of the modern color

    LCD display include:

    – A liquid crystal panel

    – A backlight as a light source

    – A thin film transistor (TFT) array

    – Polarizing filers on both sides of the

    display.

  • 64

  • 65

    • More difficult to switch resolutions.

    • Analog LCD panels can use existing

    video card and connector.

    • LCD may not have sufficient color

    depth.

    • Many don’t react as quickly as CRTs.

    Consider before selecting

    an LCD

  • 66

    Large screen LCD monitors

    are becoming a real display

    Large screen LCD monitors

    are becoming a real display

    option.

    • LCD monitors offer several

    advantages:

    – Larger effective viewing area

    – Produce a higher precision image

    – Flexible mounting options

    – No electromagnetic emissions.

  • 67

    • Evaluate panel at native and other

    required resolutions.

    – Does existing video card support

    required features?

    – Support for analog and DVI inputs?

    – Contrast ratio high enough?

    Is an LCD suitable?

  • Copyright © 2005 Heathkit Company, Inc. All rights reserved.

    Working with

    Monitors

  • 69

    Picture Adjustments

    • Reset Button

    • Degauss

  • 70

    Horizontal SizeHorizontal Size

  • 71

    Horizontal PositionHorizontal Position

  • 72

    Vertical SizeVertical SizeVertical Size

  • 73

    Vertical PositionVertical PositionVertical Position

  • 74

    Pin CushionPin Cushion

  • 75

    BowBow

  • 76

    Pin Signal

    1

    2

    3

    4

    5

    6

    7

    8

    9

    10

    11

    12

    13

    14

    15

    Pin Signal

    Red

    Green

    Blue

    Ground

    Display Data Channel

    Ground

    Red Ground

    Green Ground

    Blue Ground

    No Connection

    Sync Ground

    Ground

    Serial Data

    Horizontal Sync

    Vertical Sync (VCLK)

    Serial Clock

    VGA Cable End5

    10

    15

    1

    6

    11

  • 77

    Opening a Monitor to

    Repair It

  • 78

  • 79

    Basic Video

    Troubleshooting 101

    • Is the monitor turned on?

    • Is the monitor’s AC cord plugged in?

    • Turn up brightness/contrast controls.

    • Check the video cable.

  • 80

    Basic Video

    Troubleshooting 101

    • Check Power On Self-Test (POST) beeps.

    • Re-seat video card.

    • Check any configuration switch settings.

    • Swap video card, monitor, video cable.

  • 81

    Basic Video

    Troubleshooting 101

    Enter Safe Mode or re-load video

    driver.

  • Copyright © 2005 Heathkit Company, Inc. All rights reserved.

    Video Display

    Adapters

  • 83

    Super VGA (SVGA)• The standard for PCs and monitors.

    • Popular SVGA formats include:

    – 800 by 600 pixels

    – 1024 by 768 pixels

    – 1280 by 1024 pixels

    • The higher the resolution, the finer the detail displayed.

    • The higher the resolution; the more information displayed.

  • 84

    Video Graphics Array (VGA)

    • Resolution of 640 by 480 pixels.

    • Introduced in 1987 by IBM as the PS/2

    • First to use analog video outputs.

    • First to use square pixels so vertical and horizontal lines have the same thickness.

    • Replaced by SVGA in most applications.

  • 85

    Evolution of Video

    Display Adapters

    • 1981 CGA 320 by 200 pixels

    • 1984 EGA 640 by 350 pixels

    • 1987 VGA 640 by 480 pixels

    • Today SVGA 800 by 600 pixels, or higher.

  • 86

    VGA SVGA

  • 87

    The activities of the

    monitor are determined

    entirely by the PC.

  • 88

    The PC determines:

    • the color

    • the brightness

    • and the position

    of every pixel in the monitor’s display.

  • 89

    The PC sends five control

    signals to the monitor:

    • The Red Video Signal.

    • The Green Video Signal.

    • The Blue Video Signal.

    • The Horizontal Sync Pulse.

    • The Vertical Sync Pulse.

  • 90

    The Video Controller in

    the PC

    8-bit

    DAC

    8-bit

    DAC

    8-bit

    DAC

    8-bit

    DAC

    8-bit

    DAC

    8-bit

    DAC

    Analog

    outputs

    monitor

    Analog

    outputs

    to

    monitor

  • The Input and Output of

    the Red DAC in the PC.

    0.0 Volts

    11111111

    11111110

    .

    .

    .

    00000001

    00000000

    0.7 Volts

    Input Output

  • 92

  • Copyright © 2005 Heathkit Company, Inc. All rights reserved.

    Upgrading a

    Computer

  • 94

    Memory

    • Few computers have enough

    • What fits in this computer?

    • SIMM or DIMM?

    • SDRAM or DDR2?

    • Speed?

  • 95

    Pentium I

    • Add SIMMs in pairs

    • Check the manual for specs

  • 96

    Pentium II/III/4

    • Generally fewer free slots

    • Add one DIMM at a time

    • Bigger DIMMs are available

    • PC-66, PC-100, PC-133

  • 97

    CPU Upgrades

    • Cost vs. Benefit

    • Role of the computer

    • Can the motherboard support the

    upgrade?

    • Do you need to update the BIOS?

  • 98

    Expansion Cards

    • Before you buy the card:

    – What slot type

    – Are slots available?

    – Are the proper drivers available?

    • Win 98, Win 2000, etc.

  • 99

    Drives

    • Can the BIOS support a large drive?

    • Can the BIOS be upgraded?

    • Do you have enough power

    connectors?

    • Do you have the software tools?

    – Bootable disk with FDISK, Format,

    etc.

  • 100

    Motherboards

    • What type of case?

    – AT, ATX, Proprietary

    • What type of motherboard?

    • Do the back-panel connections

    match up?

    • Can you connect front-panel cables?

  • 101

    Motherboards

    • Can you use the old video adapter

    and memory?

    • Do you want to use the old video

    board and memory?

    • Do you need to buy a CPU, too?

    • Is this project worth the cost?

  • Copyright © 2005 Heathkit Company, Inc. All rights reserved.

    Modems

  • 103

    Local

    Exchange

    Local

    Exchange

    Local

    Exchange

    Local

    Exchange

    AnalogAnalog

    DigitalDigital

    DigitalDigital

  • 104

    Local

    Exchange

    Local

    Exchange

    Local

    Exchange

    Local

    Exchange

    AnalogAnalog

    DigitalDigital

    DigitalDigital

    ModemModem ModemModem

  • 105

    Modem-1Modem-1

    PC-1PC-1

    Modem-2Modem-2PC-2PC-2

    Phone

    System

    Phone

    System

  • 106

    Modem 1Modem-1

    PC-1PC-1

    Modem-2Modem-2

    Dial-Up ServerDial-Up Server

    Phone

    System

    Phone

    System

  • 107

    PC-1PC-1

    Dial-Up

    Server

    Dial-Up

    Server

    Phone

    System

    Phone

    System

  • 108

    Two Sets of Issues

    • Computer-to-Computer Issues

    • Client-to-Network Issues

  • 109

    CPU vs. Phone Line

    • Digital Signal

    • High Speed

    • Parallel Data

    • Analog Signal

    • Low Speed

    • Serial Data

  • 110

    Analog

    Digital

  • 111

    The Modem

    • Modulator / Demodulator

    • Converts the digital signals from the computer into the analog signals required by the telephone line.

    • Converts the analog signals from the telephone line into the digital signals required by the computer.

  • 112

    Pulse Amplitude Modulation (PAM)Pulse Amplitude Modulation (PAM)

    1 0 1 1 0 1

  • 113

    Each Amplitude Level

    Represents Two Bits

    Each Amplitude Level

    Represents Two Bits

    0001

    10

    11

  • 0º Phase Shift 90º Phase Shift

    180º Phase Shift 270º Phase Shift

    114

  • 115

    Baud• Baud - A single state change of the

    analog signal.

    • Baud Rate - The number of times per second that the analog signal changes state.

    • In early modems, one baud usually represented one bit.

    • In today’s modems, one baud represents more than one bit.

  • 116

    Low SpeedLow Speed

    High SpeedHigh Speed

  • 117

    1

    0

    1

    0

    1

    1

    1

    0

    Parallel

    10101110 SerialSerial

  • 118

    The UART

    • Universal Asynchronous

    Receiver/Transmitter

    • The heart of the Serial (COM) port.

    • Converts parallel data required by CPU

    into serial data required by serial port.

    • Converts serial data received at serial

    port into parallel data required by CPU.

  • 119

    Making the CPU and Phone

    Line Compatible (Transmit).

    CPU

    UARTUART ModemModemPhone Phone

    Line

    1.High Speed to Low Speed

    2. Parallel to Serial

    1.High Speed to Low Speed

    2. Parallel to Serial

    Digital to Digital to

    Analog

    Buffer

    Memory

    Buffer

    Memory

  • 120

    Making the CPU and Phone

    Line Compatible (Receive).

    UARTUART ModemModemPhone Phone

    Line

    CPU

    Buffer

    Memory

    Buffer

    Memory

    1.High Speed to Low Speed

    2. Parallel to Serial

    1.High Speed to Low Speed

    2. Parallel to Serial

    Digital to Digital to

    Analog

  • 121

    Two Types of Modems

    • Internal – ISA or PCI board that

    fits inside the computer.

    • External – Stand-alone box.

    Connects to one of the COM

    Ports.

  • 122

    Internal ModemInternal Modem

    CPUUART

    Function

    UART

    Function

    Modem

    Function

    Modem

    Function

    Phone Phone

    Line

    Internal Modem

  • 123

    CPU UARTUARTExternal

    Modem

    External

    Modem

    Phone Phone

    Line

    Motherboard

  • 124

    CPU UARTUARTExternal

    Modem

    External

    Modem

    Phone Phone

    Line

    Mother-

    board

    I/O

    Adapter

    Card

  • 125

    Modulation Standards

    • V.22 – 1200bps standard

    • V.22bis – 2400bps standard

    • V.32 – 9600bps standard

    • V.32bis – 14,400 standard

    • V.FC – 28,800 standard

    • V.34 – 33,600 standard

    • V.90 – 56kbps standard

  • 126

    V.42 Error-Correction

    Standards

    • Link Access Procedure for

    Modems (LAPM)

    • Microcom Networking Protocol

    – 4 (MNP-4)

  • 127

    V.42bis Compression

    Standard.

    • Uses a compression technique to

    reduce the size of out going data.

    • Can compress data up to ~ 4 to 1.

    • For example, a 33,600-bps Modem

    could transfer data at a rates up to

    about 134,400 bps.

  • 128

    The COM Port

    • Also called Serial Port or RS-232 Port

    • The link between PC and Modem.

    • The external Modem connects to COM port on back of PC via serial cable.

    • The internal Modem has built-in COM port that duplicates function of external COM port.

  • 129

    9-Pin Serial Port9-Pin Serial Port25-Pin Serial Port25-Pin Serial Port

  • 130

    Standard Modem

    COM Port Settings

    COM Port IRQ I/O Address

    (Hex)

    COM1 4 03F8

    COM2 3 02F8

    COM3 4 03E8

    COM4 3 02E8

  • 131

    CPU

    UARTUART ModemModemI/O

    Memory

    I/O

    Memory

    COM1

    IRQ4IRQ4

    03F803F8

  • 132

    CPU

    UARTUART ModemModemI/O

    Memory

    I/O

    Memory

    COM2

    IRQ3IRQ3

    02F802F8

  • 133

    134.4

    kbps

    134.4

    kbps

    134.4

    kbps

    134.4

    kbps

  • 134

    UART Speed

    • Determines the Serial Port speed.

    • 16550 UART chip can reach speeds of 256 kbps.

    • 16440 UART chip can reach speeds of 115.2 kbps.

    • 8250 UART was supplied with the original IBM XT machine.

  • 135

    Digital Subscriber Line

    (DSL) - A technique used for

    transmitting high-bandwidth

    data over twisted-pair

    telephone lines.

  • 136

    Central

    Office

    Central

    Office

    Central

    Office

    Central

    Office

    Local LoopLocal Loop

    Analog

    AnalogAnalog

  • 137

    Voice requires only about

    4kHz of bandwidth.

    0 4kHzFrequency

    VoiceVoice

  • 138

    Central

    Office

    Central

    Office

    Central

    Office

    Central

    Office

    DigitalDigital

    Local LoopLocal Loop

    Analog

  • 139

    For short distances,

    twisted-pair can handle

    frequencies much higher

    than 4kHz.

  • 140

    Connecting to the Internet

    • Modem (POTS)

    • ISDN

    • T1 line

    • Digital Subscriber Line (DSL)

  • 141

    Cost Vs. BandwidthC

    ost

    $

    Bandwidth

    Modem

    (POTS)

    Modem

    (POTS)

    ISDN

    T1

    DSL

  • 142

    Advantages of DSL

    • Always-on connectivity

    • High speed

    • Flat-rate service

    • Reliability

  • 143

    bandwidth not required by voice.

    DSL takes advantage of the

    bandwidth not required by voice.

    0 4kHzFrequency

    VoiceVoice

    1MHz

    DSLDSL

  • 144

    xDSL:

    • Asymmetric Digital Subscriber

    Line (ADSL)

    • Very High Data Rate Digital

    Subscriber Line (VDSL)

  • 145

    Asymmetric DSL – Allows

    downstream than upstream.

    Asymmetric DSL – Allows

    more bandwidth

    downstream than upstream.

    0 4kHzFrequency

    VoiceVoice DownstreamDownstream

    1MHz

    UpstreamUpstream

  • 146

    Central OfficeCentral OfficeTo/From

    ISP

    To/From

    ISP

  • 147

    Typical ADSL Typical ADSL

    Characteristics

    Data Rate Distance

    Downstream 1.5 Mbps 15,000 ft

    Upstream 16 kbps 15,000 ft

    Downstream 6.1 Mbps 9,000 ft

    Upstream 640 kbps 9,000 ft

  • 148

    DSL is distance-sensitive

    • You must be within about 12,000 to 18,000 feet of a central office.

    • The distance is the path the wire takes, not the straight-line distance.

    • Even so, the majority of the United States’ population lives and works within DSL range.

  • 149

    The DSL Provider

    • The company that delivers DSL service to your home or business.

    • Generally a phone company.

    • Many DSL providers act as their own Internet Service Provider (ISP).

    • Some areas have more than one DSL provider.

  • 150

    Customer Premises

    Equipment (CPE)

    • Telco lingo for phone or DSL

    equipment in the home or office.

    • Splitter/Filter

    • DSL Modem or DSL Router

  • 151

    0 4kHzFrequency

    VoiceVoice

    1MHz

    Splitter/FilterSplitter/Filter

    Voice/Data

    Low Pass

    High Pass

    Voice

    Data

    DataData

  • 152

    The DSL Modem

    • Low cost.

    • Requires no customer

    configuration.

    • Acts as a bridge to your DSL

    provider’s TCP/IP network.

  • 153

    CO

    Interne

    t

    ISP

    PSTNPSTN

    Analog ModemAnalog Modem

    PhonePhone

    ComputerComputer

  • 154

    DSL ModemDSL Modem

    PhonePhone

    ComputerComputer

    PSTNPSTN

    InternetInternet

    PSTN

    Switch

    PSTN

    Switch

    DSLAMDSLAM

    Central

    Office (CO)

    Splitter/Splitter/

    Filter

  • 155

    Problems with the DSL

    Modem Approach

    • Single IP address

    • The Internet Connection is not

    easily shared.

    • Security concerns.

  • 156

    The DSL Router

    • Higher cost

    • Turns your local network into a separate TCP/IP LAN.

    • May provide several services such as:

    – DHCP

    – NAT

    – Firewall

    – VPN

  • 157

    HUBHUB

    Analog ModemAnalog Modem

    Small Office/Home Office (SOHO)

    PhonePhone

    CO

    Interne

    t

    Interne

    t

    ISP

    PSTNPSTN

  • 158

    HUBHUBDSL RouterDSL Router

    Small Office/Home Office (SOHO)

    Splitter/

    Filter

    PhonePhone

    To/From

    Provider

    To/From

    DSL

    Provider

  • 159

    HUBHUBDSL RouterDSL Router

    Home/Office

    PSTNPSTN

    InternetInternet

    PSTN

    Switch

    DSLAM

    Central

    Office (CO)

    PhonePhone

    FilterFilter

  • 160

    Digital Subscriber Line

    Access Multiplexer (DSLAM)

    • Normally located at the Telco

    Central Office

    • Concentrates data from numerous

    DSL connections into a high

    capacity backbone.

    • Separates voice from data and sends

    each to its appropriate location.

  • 161

    185.132.116.103

    HUBHUBDSL RouterDSL Router

    Small Office/Home Office (SOHO)

    To/From

    Provider

    To/From

    DSL

    Provider

  • 162

    Very High Data Rate Digital

    Subscriber Line (VDSL)

    • An emerging technology

    • Promises to deliver

    – Downstream speeds of 15 to 52 Mbps.

    – Upstream speeds of 1.5 to 2.3 Mbps.

    • Over short distances (1000 to 4500 ft) of existing twisted pair phone lines.

  • 163

    Central Office

    Fiber Optic

    Cable

    Optical Network

    Unit (ONU)

    Office Building