CHAPTER 7. TELECOMMUNICATIONS NETWORKS & THE NEW INFORMATION TECHNOLOGY

LEARNING OBJECTIVES DESCRIBE COMPONENTS OF TELECOMMUNICATIONS SYSTEM CALCULATE CAPACITY OF TELECOMMUNICATIONS CHANNELS & EVALUATE TRANSMISSION MEDIA COMPARE TYPES OF NETWORKS & NETWORK SERVICES *

LEARNING OBJECTIVES DESCRIBE INFRASTRUCTURE, CONNECTIVITY STANDARDS IDENTIFY APPLICATIONS FOR SUPPORTING ELECTRONIC COMMERCE, BUSINESS ANALYZE MANAGEMENT PROBLEMS OF NETWORKING *

MANAGEMENT CHALLENGES TELECOMMUNICATIONS REVOLUTION COMPONENTS, FUNCTIONS OF TELECOMMUNICATIONS SYSTEM COMMUNICATIONS NETWORKS NETWORK INFRASTUCTURE MANAGEMENT ISSUES, DECISIONS *

COMMUNICATING INFORMATION TELECOMMUNICATIONS COMMUNICATING INFORMATION VIA ELECTRONIC MEANS OVER SOME DISTANCE *

INFORMATION SUPERHIGHWAY NATIONAL / WORLDWIDE HIGH SPEED DIGITAL TELECOMMUNICATIONS ACCESSIBLE BY GENERAL PUBLIC *

SYSTEM COMPONENTS COMPUTERS TERMINALS (Input / output devices) COMMUNICATIONS CHANNELS PROCESSORS (Modems; multiplexers; front-end processors) COMMUNICATIONS SOFTWARE *

TO GOVERN TRANSMISSION PROTOCOL RULES & PROCEDURES TO GOVERN TRANSMISSION BETWEEN COMPONENTS IN A NETWORK *

ANALOG SIGNAL CONTINUOUS WAVEFORM PASSES THRU SYSTEM VOICE COMMUNICATIONS *

DIGITAL SIGNAL DISCRETE WAVEFORM TWO DISCRETE STATES: 1-BIT & 0-BIT ON / OFF PULSE DATA COMMUNICATION USES MODEM TO TRANSLATE ANALOG TO DIGITAL, DIGITAL TO ANALOG * 0010111010011101001010101110111100100010000101111010110100111010010010110010101101100

COMMUNICATION CHANNELS MEANS BY WHICH DATA ARE TRANSMITTED: TWISTED WIRES (Copper Wires) COAXIAL CABLE: (Insulated Copper Wires) FIBER-OPTIC CABLE MICROWAVE *

FIBER OPTICS SUPER CLEAR GLASS STRANDS FAST, LIGHT, DURABLE BILLIONS OF BITS PER SECOND, FULL DUPLEX EXPENSIVE, HARDER TO INSTALL OFTEN USED AS BACKBONE OF NETWORKS * SIGNAL LASER CABLE PHOTO DETECTOR

MICROWAVE TRANSMISSION ORBITING SATELLITES MICROWAVE TRANSMISSION UPLINK DOWNLINK

WIRELESS TRANSMISSION TECHNOLOGIES PAGING SYSTEM: Small pager beeps when receives short message CELLULAR TELEPHONE: Device uses radio waves to reach antennas within areas called cells MOBILE DATA NETWORKS: Radio - based data network using hand-held computers; cheap, efficient *

WIRELESS TRANSMISSION TECHNOLOGIES PERSONAL COMMUNICATION SERVICE: Cellular; lower power; higher frequency. Smaller phones not shielded by buildings, tunnels PERSONAL DIGITAL ASSISTANT: Pen sized, hand-held, digital communicator SMART PHONE: Wireless, voice, text, Internet *

COMMUNICATIONS CHANNELS TRANSMISSION SPEED: Bits per Second (BPS) or Baud BANDWIDTH: Capacity of Channel; Difference between Highest & Lowest Frequencies *

SPEEDS & COST OF MEDIA MEDIUM SPEED COST TWISTED WIRE 300 BPS - 10 MBPS LOW MICROWAVE 256 KBPS - 100 MBPS SATELLITE COAXIAL CABLE 56 KBPS - 200 MBPS FIBER OPTICS 500 KBPS - 10 GBPS HIGH BPS: BITS PER SECOND KBPS: KILOBITS PER SECOND MBPS: MEGABITS PER SECOND GBPS: GIGABITS PER SECOND

COMMUNICATIONS PROCESSORS FRONT- END PROCESSOR: minicomputer manages communication for host computer CONCENTRATOR: computer collects messages for batch transmission to host computer CONTROLLER: computer controls interface between CPU and peripheral devices MULTIPLEXER: allows channel to carry multiple sources simultaneously *

NETWORK TOPOLOGIES HOST USER STAR

NETWORK TOPOLOGIES USER BUS

NETWORK TOPOLOGIES USER RING

LOCAL NETWORKS PRIVATE BRANCH EXCHANGE (PBX): firm’s central switching system LOCAL AREA NETWORK (LAN): dedicated channels; limited distance (less than 2000 foot radius); higher capacity than PBX. Can share expensive hardware & software *

LOCAL AREA NETWORK (LAN) GATEWAY: Connection to other networks ROUTER: Forwards data to other networks NETWORK OPERATING SYSTEM (NOS): Manages file server; routes communications on network PEER - TO - PEER: In some small networks all computers have equal power *

WIDE - AREA NETWORK (WAN) Network spans large geographic distances. Can include cable, satellite, microwave SWITCHED LINES: Route determined by current traffic DEDICATED LINES: Constantly available for high-volume traffic *

VALUE-ADDED NETWORK (VAN) PRIVATE; MULTIPATH; DATA ONLY 3rd PARTY MANAGED USED BY SEVERAL ORGANIZATIONS SUBSCRIPTION BASIS *

NETWORK SERVICES PACKET SWITCHING FRAME RELAY ASYNCHRONOUS TRANSFER MODE (ATM) INTEGRATED SERVICES DIGITAL NETWORK (ISDN) DIGITAL SUBSCRIBER LINE CABLE MODEM T1 LINE *

PACKET SWITCHING (X.25): FORM OF Value Added Network BREAKS DATA BLOCKS INTO SMALL PACKETS (e.g.: 128 Bytes) PACKETS ROUTED BY MOST ECONOMICAL MEANS REASSEMBLED AT DESTINATION *

ASYNCHRONOUS TRANSFER MODE (ATM): CELL: 53 Groups of 8 Bytes Each USES FIBER OPTICS CABLE INDEPENDENT OF VENDOR HARDWARE SPEEDS CAN TIE LAN TO WAN *

INTEGRATED SERVICES DIGITAL NETWORK (ISDN): INTERNATIONAL STANDARD FOR TRANSMITTING VOICE, VIDEO, DATA OVER PUBLIC TELEPHONE LINES *

OTHER SERVICES: DIGITAL SUBSCRIBER LINE (DSL): enhancing capacity over copper telephone lines CABLE MODEM: modem for cable TV for high-speed access to Internet T1 LINE: dedicated telephone connection, 24 channels @ 1.544 megabits per second *

OTHER SERVICES: BROADBAND: High-speed transmission, multiple channels CONVERGING NETWORK: Enables simultaneous transmission of voice, data *

ENTERPRISE NETWORK HARDWARE; SOFTWARE; TELECOMMUNICATIONS, DATA RESOURCES MORE COMPUTING POWER ON THE DESKTOP NETWORK LINKING SMALLER NETWORKS *

INTO INTERCONNECTED NETWORK INTERNETWORKING LINK NETWORKS EACH RETAINS IDENTITY INTO INTERCONNECTED NETWORK * NETWORK A NETWORK B NETWORK C

CONNECTIVITY MEASURE OF ABILITY OF COMPUTING DEVICES TO PASS & SHARE INFORMATION WITHOUT HUMAN INTERVENTION OPEN SYSTEMS: Software able to function on different computer platforms. Nonproprietary operating systems, applications, protocols *

TRANSMISSION CONTROL PROTOCOL / INTERNET PROTOCOL (TCP / IP) REFERENCE MODEL DEVELOPED BY DEPARTMENT OF DEFENSE IN 1972 1. APPLICATION: Provides screen presentations 2. TRANSMISSION CONTROL PROTOCOL (TCP): Breaks data into datagrams 3. INTERNET PROTOCOL (IP): Breaks, sends datagrams as smaller IP packets; can repeat transmission to increase reliability *

TRANSMISSION CONTROL PROTOCOL / INTERNET PROTOCOL (TCP / IP) 4. NETWORK INTERFACE: Handles addressing and interface between computer & network 5. PHYSICAL NET: Defines electrical transmission characteristics for sending signal along networks to destination *

OPEN SYSTEM INTERCONNECT (OSI) INTERNATIONAL REFERENCE MODEL FOR LINKING DIFFERENT TYPES OF COMPUTERS & NETWORKS *

E-COMMERCE & E-BUSINESS TECHNOLOGIES ELECTRONIC MAIL (e-mail) VOICE MAIL FACSIMILE MACHINES (fax) TELECONFERENCING DATACONFERENCING VIDEOCONFERENCING GROUPWARE *

ELECTRONIC DATA INTERCHANGE (EDI) COMPUTER - TO - COMPUTER EXCHANGE BETWEEN TWO ORGANIZATIONS OF STANDARD BUSINESS TRANSACTION DOCUMENTS * COMPUTER SELLER CUSTOMER ORDERS, PAYMENTS SHIPPING NOTICES, PRICE UPDATES, INVOICES

PROBLEMS POSED BY ENTERPRISE NETWORKING CONNECTIVITY LOSS OF MANAGEMENT CONTROL ORGANIZATIONAL CHANGE REQUIREMENTS HIDDEN COSTS OF CLIENT/SERVER COMPUTING RELIABILITY & SECURITY *

HIDDEN COSTS OF CLIENT / SERVER SYSTEMS OPERATIONS & SUPPORT APPLICATION DEVELOPMENT HARDWARE, SOFTWARE, INSTALLATION, MAINTENANCE EDUCATION & TRAINING *

TELECOMMUNICATIONS PLAN: KNOW LONG-RANGE PLANS AUDIT EXISTING CAPABILITIES IDENTIFY, PRIORITIZE CRITICAL IMPROVEMENTS ENHANCE FIRM’S STRATEGIC POSITION IMPLEMENT PLAN *

IMPLEMENTATION FACTORS DISTANCE RANGE OF SERVICES SECURITY MULTIPLE ACCESS UTILIZATION COST INSTALLATION CONNECTIVITY *

Connect to the INTERNET Laudon/Laudon Web site: http://www.prenhall.com/laudon Additional Internet Resources related to this chapter: http://www.sap.com http://www.mysap.com http://www.peoplesoft.com http://www.oec.com http://www.novell.com http://www.microsoft.com http://samba.anu.edu.au/samba http://www.wpine.com http://www.microsoft.com/netmeeting http://wwwhost.ots.utexas.edu/ethernet/ © 2001 Laudon & Laudon, Essentials of Management Information Systems 4/e

CHAPTER 7. TELECOMMUNICATIONS NETWORKS & THE NEW INFORMATION TECHNOLOGY