1 pertemuan 3 komputer h/w, s/w, network & telekomunikasi matakuliah: h0472 / konsep sistem...

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Pertemuan 3Komputer H/W, S/W, Network &

Telekomunikasi

Matakuliah : H0472 / Konsep Sistem Informasi

Tahun : 2006

Versi : 1

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Learning Outcomes

Pada akhir pertemuan ini, diharapkan mahasiswa

akan mampu :

• Menerangkan teknologi komputer dalam mendukung konsep work sistem

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Outline Materi

• Overview sistem komputer

• Overview S/W, programming

• Overview Telekomunikasi

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COMPUTER GENERATIONS

1. VACUUM TUBES: 1946-1959

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COMPUTER GENERATIONS

1. VACUUM TUBES: 1946-1959

2. TRANSISTORS: 1957-1963

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COMPUTER GENERATIONS

1. VACUUM TUBES: 1946-1959

2. TRANSISTORS: 1957-1963

3. INTEGRATED CIRCUITS: 1964-1979

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COMPUTER GENERATIONS

1. VACUUM TUBES: 1946-1959

2. TRANSISTORS: 1957-1963

3. INTEGRATED CIRCUITS: 1964-1979

4. VERY LARGE-SCALE INTEGRATED (VLSI) CIRCUITS: 1980- PRESENT

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SUPERCOMPUTERTERAFLOP: TRILLION CALCULATIONS/SECOND

• HIGHLY SOPHISTICATED

• COMPLEX COMPUTATIONS

• FASTEST CPUs

• LARGE SIMULATIONS

• STATE-OF-THE-ART COMPONENTS

• EXPENSIVE

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MAINFRAME

• LARGEST ENTERPRISE COMPUTER

• 5O MEGABYTES TO OVER ONE GIGABYTE RAM

• COMMERCIAL, SCIENTIFIC, MILITARY APPLICATIONS

• MASSIVE DATA

• COMPLICATED COMPUTATIONS

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MIPS: Millions of Instructions per secondMIPS: Millions of Instructions per second

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MINICOMPUTER

• MIDDLE-RANGE

• 10 MEGABYTES TO OVER ONE GIGABYTE RAM

• UNIVERSITIES, FACTORIES, LABS

• USED AS FRONT-END PROCESSOR FOR MAINFRAME

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• DESKTOP OR PORTABLE• 64 KILOBYTES TO OVER 128

MEGABYTES RAM• PERSONAL OR BUSINESS COMPUTERS• AFFORDABLE• MANY AVAILABLE COMPONENTS• CAN BE NETWORKED

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MICROCOMPUTER

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LAPTOPS & SMALLER

• LAPTOP (OR NOTEBOOK): Briefcase type package, very portable, can be inexpensive, can connect to other computers or networks

• HAND-HELD (OR PALMTOP): Sub-miniature, wireless computer. Growing in sophistication and connectivity

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BASIC COMPONENTS OF COMPUTER SYSTEMS

• UNDERLYING STRUCTURE

• INPUT/OUTPUT

• BITS & CODING SCHEMES

• ARITHMETIC LOGIC UNIT

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CENTRAL PROCESSING UNIT (CPU)

RAMRAM

PRIMARY (MAIN) MEMORYPRIMARY (MAIN) MEMORY

CONTROL UNITCONTROL UNITARITHMETIC/LOGICARITHMETIC/LOGIC

UNITUNIT

ROMROMCLOCKCLOCK

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BUSES

CPUCPUPRIMARYPRIMARY

STORAGESTORAGE

DATA BUSDATA BUS

ADDRESS BUSADDRESS BUS

CONTROL BUSCONTROL BUS

INPUT

DEVICES

OUTPUT

DEVICES

SECONDARY

STORAGE

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TYPES OF MEMORY

• RAM : Random Access Memory– Dynamic: Changes thru processing– Static: Remains constant (power on)

• ROM : Read Only Memory (preprogrammed)– PROM: Program can be changed once– EPROM: Erasable thru ultraviolet light– EEPROM: Electrically erasable

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INPUT/OUTPUT

• TERMINAL• POINT-OF-SALES TERMINALS• AUTOMATIC TELLER MACHINES• PUNCHED CARDS• MAGNETIC INK CHARACTER RECOGNITION

(MICR): Used by banks to process checks

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INPUT/OUTPUT

• OPTICAL CHARACTER RECOGNITION: Scanned material translated into computer characters

• IMAGING: Forms, documents, photos digitized for computer use

• BAR CODE LABEL: Product label information read into computer. Can be used to track inventory

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INPUT/OUTPUT

• COMPUTER OUTPUT MICROFILM (COM): Computer rapidly generates microfilm documents for archive copies in small space

• VOICE RESPONSE UNITS: Computer recognizes, generates verbal messages

• MULTIMEDIA: Combines text, graphics, sound still images, animations, video

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• BIT: Binary Digit. On/Off, 0/1, Magnetic/Not• BYTE: Group of bits for one character

– EBCDIC- Extended Binary Coded Decimal Interchange Code (8 bits per byte)

– ASCII- American Standard Code for Information Exchange (7 or 8 bits per byte)

• PARITY BIT: extra bit added to each byte to help detect errors

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HOW CHARACTERS ARE STORED IN COMPUTER MEMORY

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EXAMPLES OF BYTES

C: 1100 0011 0 100 0011 1

A: 1100 0001 1 100 0001 0

T: 1110 0011 1 101 0100 1

Note how sum for each byte is an EVEN number

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EBCDICEBCDIC ASCII ASCII (assume even-parity system)(assume even-parity system)

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ALU & CONTROL UNIT

• ARITHMETIC- LOGIC UNIT: CPU component performs logic and arithmetic operations

• CONTROL UNIT: CPU component controls, coordinates other parts of computer system

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COMPUTER FILES

• RECORD: Data about a transaction arranged in a set of FIELDS, each holding a datum

• FILE: A group of similar records, such as accounts receivable or payroll

• DATABASE: The files of an organization, an electronic library

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COMPUTER FILES

• SEQUENTIAL ACCESS: A sequence of files arranged in order, say alphabetically. Usually stored on magnetic tape or cartridge

• DIRECT ACCESS: Records stored on a DIRECT ACCESS STORAGE DEVICE (DASD). Can move directly to any record

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DIRECT ACCESS STORAGE DEVICE

• HARD DISK: Steel platter array for large computer systems

• RAID: Redundant array of Inexpensive Disks

• FLOPPY DISK: Removable disk for PC

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DISK PACK STORAGE

• LARGE SYSTEMS

• RELIABLE STORAGE

• LARGE AMOUNTS OF DATA

• QUICK ACCESS & RETRIEVABLE

• TYPICAL: 11 2-SIDED DISKS

• CYLINDER: SAME TRACK ALL SURFACES

CYLINDER 10: TRACK 10 (TOP AND BOTTOM OF EACH DISK)CYLINDER 10: TRACK 10 (TOP AND BOTTOM OF EACH DISK)

DISK 1DISK 1DISK 2DISK 2DISK 3DISK 3DISK 4DISK 4DISK 5DISK 5

READ/WRITEREAD/WRITEHEADSHEADS

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THE STORED PROGRAM CONCEPT

• COMPUTER IS A BINARY SYSTEM

• PROGRAM: A set of instructions telling the computer what to do

• INSTRUCTION: Individual step or operation in a program

• MACHINE LANGUAGE: Translated instruction understood by particular model of computer

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CONTROLLER

• LINK FOR INPUT/OUTPUT OR FILE DEVICES: To CPU and memory of large computer systems

• HIGHLY SPECIALIZED PROCESSOR: Manages the operation of attached devices to free the CPU from these tasks

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DATA CHANNEL

• SPECIALIZED INPUT/OUTPUT PROCESSOR (A COMPUTER): Takes over function of device communication from the CPU

• CORRECTS FOR SPEED MISMATCH BETWEEN SLOW PERIPHERAL DEVICES AND VERY FAST CPU

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SYMMETRIC MULTIPROCESSOR

• PROCESSORS (CPUs) ARE IDENTICAL, WITH EACH PROCESSOR OPERATING INDEPENDENTLY OF THE OTHERS

• USED IN MOST MAINFRAMES AND SOME MIDRANGE MACHINES

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PARALLEL PROCESSOR (PP)

• MULTIPLE CPUs INSTALLED AS PART OF A SINGLE COMPUTER SYSTEM: Gives separate piece of program to each of the processors so that work on the program can proceed in parallel on the separate pieces

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MASSIVELY PARALLEL PROCESSOR (MPP)

PARALLEL PROCESSING COMPUTER WITH MANY PARALLEL PROCESSORS:

• 32 OR MORE: Different CPUs capable of performing different instructions at the same time

• 1000 OR MORE: CPUs must all carry out the same instruction at the same time

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THE STORED PROGRAM CONCEPT

• COMPUTER IS A BINARY SYSTEM

• PROGRAM: A set of instructions telling the computer what to do

• INSTRUCTION: Individual step or operation in a program

• MACHINE LANGUAGE: Translated instruction understood by particular model of computer

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Computer Software

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EVOLUTION OF COMPUTER SOFTWARE

• FIRST GENERATION: Machine language - binary language designed for particular computer

• SECOND GENERATION: Assembly language - substituted mnemonic operation codes and addresses, translated to machine language by assembler

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• THIRD GENERATION: Procedural language - FORTRAN, COBOL, C - translated to machine language by compiler or interpreter. Example: COBOL

• FOURTH GENERATION: Nonprocedural language. Tell what to do, not how to do it, order not important. Translate to machine language by compiler or interpreter. Example: FOCUS

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EVOLUTION OF COMPUTER SOFTWARE

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KEY TYPES OF SOFTWARE

• APPLICATION SOFTWARE: Programs written to accomplish particular tasks for computer users

• SUPPORT SOFTWARE: Programs that support application software in producing needed output. Does not directly produce output needed by users

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APPLICATION SOFTWARE

• WORD PROCESSING

• SPREADSHEETS

• DATABASE MANAGEMENT SYSTEMS

• PRESENTATION GRAPHICS

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APPLICATION SOFTWARE

• WORLD WIDE WEB BROWSERS

• ELECTRONIC MAIL, GROUPWARE

• DESKTOP PUBLISHING

• APPLICATION SUITES

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SUPPORT SOFTWARE

• OPERATING SYSTEMS: Helps maximize work done, eases workload of users

• JOB CONTROL LANGUAGE: Allows users to communicate with operating systems

• MULTIPROGRAMMING: Large computers can run multiple programs simultaneously. Time-driven approach is time-sharing

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SUPPORT SOFTWARE

• MULTITASKING: Allows small computers to work on several programs interactively

• VIRTUAL MEMORY: Allows computer to run portions of a large program as required, saving use of main memory

• MULTIPROCESSING: Multiple CPUs divide workload, increases efficiency

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SOURCES OF OPERATING SYSTEMS

• PROPRIETARY: Written for particular computer class or system. Examples: Windows 98, Windows 2000

• OPEN SYSTEM: Not tied to specific platform. Examples: UNIX, Linux

• NETWORK OPERATING SYSTEM (NOS): Manages network resources, local area networks

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GRAPHICAL USER INTERFACE (GUI)

• MOUSE: A standard pointing device

• ICON: Graphic or label on screen associated with task or operation

• 32-BIT OPERATING SYSTEM: Operating system handles 32 bits at a time

• CLICKING MOUSE ON ICON INITIATES TASK

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OBJECT-ORIENTED PROGRAMMING (OOP)

• COMPUTER PROGRAMMING BASED ON CREATING, USING SET OF OBJECTS: Object combines data and methods (or chunks of programs)

• EXAMPLES: C++, Smalltalk, Java

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OTHER LANGUAGES

• NATURAL LANGUAGES: User types in or speaks English, computer evolves program

• HYPERTEXT MARKUP LANGUAGE (HTML): Code used to develop World Wide Web (WWW) pages and sites

• eXtensible Markup Language (XML): Used for data exchange on WWW

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DATABASE MANAGEMENT SYSTEM (DBMS)

• SUPPORT SOFTWARE USED TO CREATE, MANAGE, AND PROTECT ORGANIZATIONAL DATA

• DBMS: Software that manages a database, works with operating system to store and modify data and to make data accessible in authorized ways

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TYPES OF DBMSs

• HIERARCHICAL: Data arranged in a top-down, organization chart fashion

• NETWORK: Data arranged like cities on a highway systems, often with multiple paths between pieces of data

• RELATIONAL: Data arranged into simple tables, and records are related by storing common data in each of the associated tables

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FILING METHODS

• INDEXED SEQUENTIAL ACCESS METHOD (ISAM) :– EACH RECORD IDENTIFIED BY KEYEACH RECORD IDENTIFIED BY KEY– GROUPED IN BLOCKS AND CYLINDERSGROUPED IN BLOCKS AND CYLINDERS– KEYS IN INDEXKEYS IN INDEX

• VIRTUAL STORAGE ACCESS METHOD (VSAM) :– MEMORY DIVIDED INTO AREAS & INTERVALSMEMORY DIVIDED INTO AREAS & INTERVALS– DYNAMIC FILE SPACEDYNAMIC FILE SPACE

VSAM WIDELY USED FOR RELATIONAL DATABASES

• DIRECT FILE ACCESS METHOD*

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COMPONENTS OF DBMS:

• DATA DEFINITION LANGUAGE: Defines data elements in database

• DATA MANIPULATION LANGUAGE: Manipulates data for applications

• DATA DICTIONARY/DIRECTORY: Formal definitions of all variables in database, controls variety of database contents

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STRUCTURED QUERY LANGUAGE (SQL)

EMERGING STANDARD

DATA MANIPULATION LANGUAGE

FOR RELATIONAL DATABASES

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ADVANTAGES OF RELATIONAL DBMS

• NEW DATA ELEMENTS CAN EASILY BE ADDED AS NEW NEEDS ARISE

• NEW RELATIONSHIPS CAN BE CREATED AS NEW QUERY/REPORTING NEEDS CHANGE

• FEWER DATA CONSISTENCY PROBLEMS DUE TO LESS REDUNDANT DATA STORAGE

• MORE “USER FRIENDLY” TOOLS

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COMPUTER-AIDED SOFTWARE ENGINEERING (CASE)

• HELPS AUTOMATE SOFTWARE DEVELOPMENT: Used by computer professionals to help automate software development

• MAY INCLUDE:– upper-CASE (requirements definition and design)

– lower-CASE (code generation)– I-CASE or integrated-CASE

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CHANGING NATURE OF SOFTWARE

• MORE HARDWIRING OF SOFTWARE AND MORE MICROCODE

• MORE COMPLEXITY OF HARDWARE/SOFTWARE ARRANGEMENTS

• LESS CONCERN WITH MACHINE EFFICIENCY

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• MORE PURCHASED APPLICATIONS AND MORE PORTABILITY OF THESE APPLICATIONS FROM ONE COMPUTER PLATFORM TO ANOTHER

• MORE PROGRAMMING USING OBJECT-ORIENTED AND VISUAL LANGUAGES, IN LARGE PART BECAUSE OF EMPHASIS ON GUIs

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CHANGING NATURE OF SOFTWARE

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• MORE EMPHASIS ON APPLICATIONS THAT RUN ON INTRANETS AND THE INTERNET

• MORE USER DEVELOPMENT• MORE USE OF PERSONAL PRODUCTIVITY

SOFTWARE ON MICROCOMPUTERS, ESPECIALLY PACKAGES WITH A GUI

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CHANGING NATURE OF SOFTWARE

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Telecommunications & Networking

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• TELECOMMUNICATIONS: Communications (both voice and data) at a distance

• NETWORKING: Electronic linking of geographically dispersed devices

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TELECOMMUNICATIONS & NETWORKING

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THE NEED FOR NETWORKING

• SHARING OF TECHNOLOGY RESOURCES• SHARING OF DATA• DISTRIBUTED DATA PROCESSING AND

CLIENT/SERVER SYSTEMS• ENHANCED COMMUNICATIONS, INCLUDING

ELECTRONIC DATA INTERCHANGE (EDI) AND ACCESS TO THE INTERNET

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KEY ELEMENTS OF TELECOMMUNICATIONS & NETWORKING

• ANALOG SIGNALS: Continuous waveform, passes thru system. Example: voice communications

• DIGITAL SIGNALS: Discrete waveform two discrete states (1-bit & 0-bit, on / off pulse). Data communication. Uses modem to translate analog to digital, digital to analog

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MODEM

• ABBREVIATION FOR MODULATOR/ DEMODULATOR

• DEVICE THAT CONVERTS DATA FROM DIGITAL FORM TO ANALOG FORM TO BE SENT OVER ANALOG TELEPHONE NETWORK (RECONVERTS DATA AFTER IT HAS BEEN TRANSMITTED)

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SPEED OF TRANSMISSION

• BANDWIDTH: Difference between highest and lowest frequencies (cycles per second) that can be transmitted on a particular medium; a capacity measure

• HERTZ: Cycles per second

• BAUD: Signals sent per second

• BITS PER SECOND (bps): Common measure

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TYPES OF TRANSMISSION LINES

• PRIVATE, OR DEDICATED, LINES

• SWITCHED LINES

• SIMPLEX TRANSMISSION

• HALF-DUPLEX TRANSMISSION

• FULL-DUPLEX TRANSMISSION

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TRANSMISSION MEDIA

• TWISTED PAIR

• COAXIAL CABLE: Baseband and broadband

• WIRELESS: Cordless phone, cellular phone, wireless LAN, infrared devices

• SATELLITE: Microwave, line of sight

• FIBER OPTICS

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ORBITING SATELLITES

UPLINKUPLINK

MICROWAVE MICROWAVE TRANSMISSIONTRANSMISSION

DOWNLINKDOWNLINK

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NEW SATELLITES

• OVER A DOZEN NEW PROJECTS PROPOSED

• LOW EARTH ORBIT (LEO) SATELLITES: Only 400 to 1000 miles above the earth, compared to geosynchronous satellites at 22,000 miles above the equator. 1,700 satellites to be launched by 2006

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NEW SATELLITES

• IRIDIUM: 66 satellites offered mobile telephony, paging, and data communications. Bankrupt by 1999.

• TELEDESCIC: Will include 288 LEO to provide low-cost, high-speed Internet access, networking, teleconferencing

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TELECOMMUNICATIONS TRANSMISSION SPEEDS

• Twisted pair - voice telephone 14.4 kbps -56 kbps• Twisted pair - conditioned 56 kbps - 144 kbps• Twisted pair - LAN 4 mbps - 100 mbps• Coaxial cable - baseband 10 mbps - 2 gbps• Coaxial cable - broadband 10 mbps - 550 mbps• Radio frequency wireless LAN 1 mbps - 11 mbps• Infrared light wireless LAN 4 mbps - 16 mbps• Microwave / Satellite 64 kbps - 100 mbps• Fiber optic cable 100 mbps - 100 gbps

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TOPOLOGY OF NETWORKS

• BUS TOPOLOGY

• RING TOPOLOGY

• STAR TOPOLOGY

• TREE, OR HIERARCHICAL, TOPOLOGY

• MESH TOPOLOGY

• MORE COMPLEX TOPOLOGIES

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NETWORK TYPES

• COMPUTER TELECOMMUNICATIONS NETWORK

• PRIVATE BRANCH EXCHANGE (PBX) NETWORK

• LOCAL AREA NETWORK (LAN)

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NETWORK TYPES

• BACKBONE NETWORK

• WIDE AREA NETWORK (WAN)

• INTERNET

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LOCAL AREA NETWORKS

• CONTENTION BUS NETWORK: Uses CSMA/CD protocol. Example: Ethernet

• TOKEN BUS NETWORK: Central to Manufacturing Automation Protocol (MAP)

• TOKEN RING NETWORK: Used in LAN; unidirectional data flow

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NEW LAN TECHNOLOGY

• FAST ETHERNET: Ethernet operating at speeds up to 100 mbps

• FIBER DISTRIBUTED DATA INTERFACE (FDDI): Token ring architecture delivered on a dual ring at speeds up to 100 mbps

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BACKBONE NETWORKS

• MIDDLE DISTANCE NETWORKS: Interconnect LANs in a single organization with each other and with the organization’s WAN and Internet

• EMPLOY HIGH-END LAN TECHNOLOGY, OFTEN OPERATING AT 100 MBPS OR MORE

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• HUB: Simple device connecting one section of a LAN to another

• BRIDGE: Connects two LAN segments when the LANs use the same protocols

• ROUTER, OR GATEWAY: Connects two or more LANs together. Networks may use different protocols

• SWITCH: Connects more than two LANs that use the same protocol into a backbone network

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BACKBONE NETWORK TERMINOLOGY

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WIDE AREA NETWORKS

• DIRECT DISTANCE DIALING (DDD)• WIDE AREA TELEPHONE SERVICE (WATS)• LEASED LINE: Most common, T-1 lines• SATELLITE: C-Band, KU-Band• VALUE ADDED NETWORK (VAN)• INTEGRATED SERVICES DIGITAL NETWORK

(ISDN)

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VALUE ADDED NETWORK (VAN)

• DATA-ONLY, PRIVATE, NONREGULATED TELECOMMUNICATIONS NETWORK: Uses packet switching

• AN ORGANIZATION MAY CHOOSE TO BUY SERVICES OF A VAN TO IMPLEMENT ITS WIDE AREA NETWORK (WAN)

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PACKET SWITCHING

• INFORMATION DIVIDED INTO PACKETS OF SOME FIXED LENGTH, SENT OVER NETWORK SEPARATELY

• PERMITS MORE EFFICIENT USE OF THE NETWORK

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INTEGRATED SERVICES DIGITAL NETWORK (ISDN)

• EMERGING SET OF INTERNATIONAL STANDARDS

• USING PUBLIC TELEPHONE NETWORK• EXTENSIVE NEW TELECOMMUNICATIONS

CAPABILITIES• SIMULTANEOUS TRANSMISSION OF VOICE

AND DATA OVER SAME LINE TO TELEPHONE USERS WORLDWIDE

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USES OF ISDN

• CUSTOMER SERVICE APPLICATION: Customer’s records automatically sent to service representative’s workstation when customer calls in

• SOLVES DIAL-IN PROBLEMS INTO CORPORATE NETWORK FOR TELECOMMUTERS, BRANCH OFFICES

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NEW WAN AND LAN TECHNOLOGY

ASYNCHRONOUS TRANSFER MODE (ATM): Switching technology employing fast packet switching. Emerging standard for broadband ISDN. Speeds from 1.544 mbps to 622 mbps. Represents the future for both LANs and WANs

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PROTOCOL

RULES & PROCEDURES

TO GOVERN TRANSMISSION

BETWEEN COMPONENTS

IN A NETWORK

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NETWORK PROTOCOLS

• OPEN SYSTEMS INTERCONNECTION (OSI): Reference model, emerging standard

• TRANSMISSION CONTROL PROTOCOL / INTERNET PROTOCOL (TCP/IP): Standard used on the Internet

• SYSTEMS NETWORK ARCHITECTURE (SNA): IBM standard

• FILE TRANSFER PROTOCOL (FTP): Allows file transfer on Internet

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INTERNET

• NETWORK OF NETWORKS THAT USE THE TCP/IP PROTOCOL, WITH GATEWAYS (CONNECTIONS) TO OTHER NETWORKS THAT DO NOT USE TCP/IP

• INTERNET APPLICATIONS: e-mail, Usenet newsgroups, listserv, FTP, Gopher, Archie, Veronica, World Wide Web

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CONNECTIONS TO INTERNET

• PHONE LINE MODEM

• CABLE MODEM

• DIGITAL SUBSCRIBER LINE (DSL)

• T-1 DATA PHONE LINE

• SATELLITE

• FIBER OPTICS

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INTRANET

• A NETWORK OPERATING WITHIN AN ORGANIZATION EMPLOYING TCP/IP PROTOCOL

• ORGANIZATION USES SAME WEB BROWSER, CRAWLER, SERVER SOFTWARE AS IT WOULD ON THE INTERNET, BUT INTRANET IS NOT ACCESSIBLE FROM OUTSIDE THE ORGANIZATION

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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

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Closing

• Overview sistem komputer

• Overview S/W, programming

• Overview Telekomunikasi