sim bab-11 komunikasi data
TRANSCRIPT
Chapter 11Data CommunicationsData Communications
MANAGEMENT INFORMATION SYSTEMS 8/E
Raymond McLeod, Jr. and George Schell
Copyright 2004 Prentice-Hall, Inc.
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Communication BasicsCommunication Basics
�� Computer communications is at Computer communications is at
three levelsthree levels
–– Application level Application level
–– Computer levelComputer level
–– Communication channelCommunication channel
�� Protocol Protocol
–– Set of rules for communicationsSet of rules for communications
–– OSI StandardOSI Standard
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OSI (Open System Interconnection) OSI (Open System Interconnection)
ReferenceReference ModelModel
Layer Name Purpose
7 Application Layer Application-to-application communication
6 Presentation Layer Manage data representation conversions
5 Session Layer Establish and maintain communication channel
4 Transport Layer Guarantee end-to-end integrity of transmission
3 Network Layer Route data between network addresses
2 Data Link Layer Move data from one network address to another
1 Physical Layer Put data onto and off of the network media
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11-4
Andrew S. Tannebaum,
1996, “Computer
Network”, Third
Edition, Prentice Hall
Inc., A. Simon &
Schuster Company,
Upper Saddle River,
New Jersey 07458
11-5
Andrew S. Tannebaum, 1996, “Computer Network”, Third Edition, Prentice Hall Inc., A.
Simon & Schuster Company, Upper Saddle River, New Jersey 07458
11-6
Andrew S. Tannebaum, 1996,
“Computer Network”, Third
Edition, Prentice Hall Inc., A.
Simon & Schuster Company,
Upper Saddle River, New
Jersey 07458
ISO WebsiteISO Website
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Protocols for Computer Protocols for Computer
CommunicationCommunication
�� Early computersEarly computers
–– TerminalsTerminals
–– Sneaker netSneaker net
�� System Network Architecture (SNA)System Network Architecture (SNA)
–– Established by IBM in 1974Established by IBM in 1974
–– ProprietaryProprietary
�� TokenToken--RingRing
–– Host computer controlledHost computer controlled
–– peerpeer--toto--peerpeer 11-8
Protocols for Computer Protocols for Computer
CommunicationCommunication
�� EthernetEthernet
–– Xerox working with Intel and Digital Xerox working with Intel and Digital
Equipment Corporation developed this protocolEquipment Corporation developed this protocol
–– NonNon--proprietaryproprietary
–– Defined by IEEEDefined by IEEE
–– Works on a single transmission lineWorks on a single transmission line
–– No token is passedNo token is passed
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PacketsPackets
�� Piece of the total data to be communicated, Piece of the total data to be communicated,
combined with the address of the destination combined with the address of the destination
computer for the data and other control computer for the data and other control
information.information.
Transmission Control Protocol/Internet
Protocol (TCP/IP) is one of the more
important packet switching protocols
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Analogi Analogi PacketPacket pada pipapada pipa
Analogi Analogi PacketPacket pada pada JJalan Raalan Rayyaa
Network AddressesNetwork Addresses
�� Address Address
–– FourFour--part set of numbers part set of numbers
–– Each from 0 to 255Each from 0 to 255
�� Internet Service Providers (ISPs)Internet Service Providers (ISPs)
–– User connects through common carrierUser connects through common carrier
�� Serial Line Internet Protocol (SLIP) and Serial Line Internet Protocol (SLIP) and
PointPoint--toto--Point Protocol (PPP)Point Protocol (PPP)
–– Protocols for users at homeProtocols for users at home
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Protocols for Public Phone Protocols for Public Phone
SystemsSystems
�� X.25X.25
–– analoganalog
–– older protocololder protocol
�� Integrated Services Digital Network (ISDN)Integrated Services Digital Network (ISDN)
–– Digital Digital
–– Can carry voice, data, and videoCan carry voice, data, and video
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Protocols for Public Phone Protocols for Public Phone
Systems (cont.)Systems (cont.)
�� Frame RelaysFrame Relays
–– Move to fiber opticsMove to fiber optics
�� Asynchronous Transfer Mode (ATM)Asynchronous Transfer Mode (ATM)
–– Smaller packet sizeSmaller packet size
–– Faster transmission speedsFaster transmission speeds
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Data Communications Links theData Communications Links the
General Systems Model ElementsGeneral Systems Model Elements
Standards
ManagementInformation
processor Environment
Input Transformation Output
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