Transcript CHAPTER 1: Computer Systems

My Introduction
 Name : Kustanto
 Address: Perum. Puri Malangjiwan 3.
N0. 12. Colomadu
 Highest education: S2 TE UGM
 Concentration : Computer Systems
Informatics
Final Assessment
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Presence
Task
Midterms
Final Exams
Chapter 1 Computer Systems
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 Delay Tolerance Attend College
= 20 Minute
 College Syllabus
Chapter 1 Computer Systems
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Chaper 1.
Computer Systems
by
Kustanto
Input-Process-Output Model (IPO)
• Input: keyboard, mouse, scanner, punch cards
• Processing: CPU executes the computer program
• Output: monitor, printer, fax machine
• Storage: hard drive, optical media, diskettes, magnetic tape
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CPU and Main Memory
Central
Processing
Unit
Primary storage area
for programs and data
that are in active use
Synonymous with RAM
Chip that executes
program
commands
Intel Pentium III
Sun Sparc
Processor
Main
Memory
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Secondary Memory Devices
Secondary memory
devices provide
long-term storage,
namely:
•Hard disks
•Floppy disks
•ZIP disks
•Writable CDs
•Tapes
Central
Processing
Unit
Information is moved
between main memory
and secondary memory
as needed
Hard Disk
Main
Memory
Floppy Disk
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Input / Output Devices
Monitor
Keyboard
Monitor screen
Keyboard
Mouse
Bar code scanner
Light pen
Touch screen
Central
Processing
Unit
I/O devices allow user
interaction
Hard Disk
Main
Memory
Floppy Disk
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Architecture Components
 Hardware
 Processes data by executing instructions
 Provides input and output
 Software
 Instructions executed by the system
 Data
 Fundamental representation of facts and
observations
 Communications
 Sharing data and processing among different
systems
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Hardware Component
 Input/Output devices
 Storage Devices
 CPU
 ALU: arithmetic/logic unit
 CU: control unit
 Interface unit
 Memory
 Short-term storage for CPU calculations
Chapter 1 Computer Systems
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Memory
9278
9279
9280
9281
9282
9283
9284
9285
9286
Main memory is
divided into many
memory locations (or
cells)
Each memory cell has
a numeric address,
which uniquely
identifies it
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Storing Information
9278
9279
9280
9281
9282
9283
9284
9285
9286
10011010
Each memory cell
stores a set number of
bits (usually 8 bits, or
one byte)
Large values are
stored in consecutive
memory locations
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Typical Personal Computer
System
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CPU: Central Processing Unit
 ALU: arithmetic/logic unit
 Performs arithmetic and Boolean logical
calculations
 CU: control unit
 Controls processing of instructions
 Controls movement of data within the CPU
 Interface unit
 Moves instructions and data between the CPU
and other hardware components
 Bus: bundle of wires that carry signals and power
between different components
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The Central Processing Unit
 A CPU is also called a microprocessor
 It continuously follows the fetch-decodeexecuteRetrieve
cycle:an instruction from main memory
fetch
execute
Carry out the
instruction
decode
Determine what the
instruction is
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The Central Processing Unit
(CPU)
 The CPU contains:
Arithmetic / Logic Unit
Control Unit
Registers
Performs calculations
and decisions
Coordinates
processing
steps
Small storage
areas
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The Central Processing Unit
 The speed of a CPU is controlled by the system clock
 The system clock generates an electronic pulse at
regular intervals
 The pulses coordinate the activities of the CPU
 The speed is measured in megahertz (MHz)
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Memory
 Also known as primary storage, working
storage, and RAM (random access memory)
 Consists of bits, each of which hold a value of
either 0 or 1 (8 bits = 1 byte)
 Holds both instructions and data of a
computer program (stored program concept)
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Storage Capacity
 Every memory device has a storage capacity,
indicating the number of bytes it can hold
 Capacities are expressed in various units:
Unit
Symbol
kilobyte
KB
210 = 1024
megabyte
MB
220 (over 1 million)
GB
2
TB
240 (over 1 trillion)
gigabyte
terabyte
Number of Bytes
30
(over 1 billion)
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Memory
 Main memory is volatile - stored information is lost if
the electric power is removed
 Secondary memory devices are nonvolatile
 Main memory and disks are direct access devices information can be reached directly
 The terms direct access and random access are
often used interchangeably
 A magnetic tape is a sequential access device since
its data is arranged in a linear order - you must get
by the intervening data in order to access other
information
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RAM vs. ROM
 RAM - Random Access Memory (direct access)
 ROM - Read-Only Memory
 The terms RAM and main memory are basically
interchangeable
 ROM could be a set of memory chips, or a separate
device, such as a CD ROM
 Both RAM and ROM are random (direct) access
devices!
 RAM should probably be called Read-Write Memory
ROM
RAM
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Monitor
 The size of a monitor (17") is measured
diagonally, like a television screen
 Most monitors these days have multimedia
capabilities: text, graphics, video, etc.
 A monitor has a certain maximum resolution ,
indicating the number of picture elements,
called pixels, that it can display (such as 1280
by 1024)
 High resolution (more pixels) produces
sharper pictures
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Modem
 Data transfer devices allow information to be sent and received
between computers
 Many computers include a modem, which allows information to
be moved across a telephone line
 A data transfer device has a maximum data transfer rate
 A modem, for instance, may have a data transfer rate of 56,000
bits per second (bps)
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Networks
 A network is two or more computers that are
connected so that data and resources can be shared
 Most computers are connected to some kind of
network
 Each computer has its own network address, which
uniquely identifies it among the others
 A file server is a network computer dedicated to
storing programs and data that are shared among
network users
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A Computer Specification
 Consider the following specification for
a personal computer:
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600 MHz Pentium III Processor
256 MB RAM
16 GB Hard Disk
24x speed CD ROM Drive
17” Multimedia Video Display with 1280 x
1024 resolution
 56 KB Modem
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Interconnection system computer
CPU
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Software Component
 Applications
 Operating System
 API: application program
interface
 File management
 I/O
 Kernel
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Memory management
Resource scheduling
Program communication
Security
 Network Module
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Communications Component
 Hardware
 Communication channels
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Physical connections between computer systems
Examples: wire cable, phone lines, fiber optic cable,
infrared light, radio waves
 Interface hardware
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Handles communication between the computer and the
communication channel
Modem or network interface card (NIC)
 Software
 Network protocols: HTTP, TCP/IP, ATAPI
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Computer Systems
All computer systems, consists of the following:
 At least one CPU
 Memory to hold programs and data
 I/O devices
 Long-term storage
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Protocols
 Common ground rules of
communication between computers, I/O
devices, and many software programs
 Examples
 HTTP: between Web servers and Web
browsers
 TCP/IP: between computers on the
Internet and local area networks
 ATAPI: between a CPU and CD-ROMs
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Standards
 Created to ensure universal compatibility of
data formats and protocols
 May be created by committee or may become
a de facto standard through popular use
 Examples:
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Computer languages: Java, SQL, C, JavaScript
Display standards: Postscript, MPEG-2, JPEG, GIF
Character set standards: ASCII, Unicode, EBCDIC
Video standards: VGA, XGA, RGB
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Chapter 5
Telecommunications System
Telecommunication model
O’Brien 125
 Terminals
 office equipment , telephones , ...
 Telecommunications processors
 modems, multiplexers, front-end processors, ...
 Telecommunications channels and media
 copper wires, coaxial cables, fiber optic cables, satellites, ...
 Computers
 host computers, network servers, ...
 Telecommunications control software
 telecommunication monitors, network operating systems, ...
Telecommunication Components
O’Brien 126
5 components
Telecom
Channels and Media
Telecommunications
software
Telecom
processors
End-user
workstation
Telecom
processors
Computers
LAN
PC-workstation
O’Brien 127 - 128
PC-workstation
PC-workstation
Databases and
Software packages
Shared hard disk
Network
Server
Shared
printer
PC-workstation
PC-workstation
PC-workstation
Port to
other networks
WAN - Internetwork
LAN’s
Mainframe,
hosts
network
in US
network
in Europe
LAN’s
Internet
network
in Australia
Cisco corporation network
Client/server network
Company A
Internet
Router
Firewall
Intranet
Firewall
Router
Company B
text: O’Brien p 178
Intranet
Mainframe host system
Client - Server
Clients
DB.
server
Print
server
server
comm.
server
Clients
DB.
server
server
comm.
server
The Internetwork-enterprise
The Internet
Intranets
Extranets
Enterprise
Intranets
Intranets
Supplier
Client
Intranets
Electronic Commerce
Other Organizations
text: O’Brien p 180
Media and Channels
 Signals
Medium
Metal wire
Microwave
Fiber optics
 analog
 digital
 Cables
 Twisted-pair
 Coaxial cable
Transmission speed
.0012Mbps - 10 Mbps
.256 Mbps - 100Mbps
.5Mbps - 1,000Mbps
interference
20x more expensive
5.500 simultaneous phone calls
 Fiber-optic
1 fiber 30.000 phone calls
 Wireless
 microwave
 satellites
 Radio, Infrared, Cellular Radio, Mobile computing
 GPS global positioning system
text: O’Brien p183 - 186
Communication hardware
 Modems 9.600 14.400 28.800 bps
 Transmission mode
 Simplex
 Half-duplex
 Full duplex
1 circuit , 1 direction
1 circuit, 2 directions, difficult co-ordination
2 circuits, 2 directions
 Transmission accurateness
 parity bits forward and backward error correction
 Processors
 multiplexers frequency, time or statistic time distribution
 front-end processors to handle routine communication tasks
with peripheral equipment
text: O’Brien p 187 - 189
Network Topology
 Star
 all communications go via the central
system
 Bus
 can easily be extended at the ends
 Ring
 more secure
Star network
O’Brien 147 - 148
With direct
connections
Point-to-point lines
- Efficient , also for high speeds
- With a large number of workstations cabling might be a problem
Star network (multiplexed)
Access via
multiplexed
lines
eventually rented
- local speed up to 2000 char/sec , 1M char/sec very expensive
- internationally 1000 char/sec commonly available
Bus network
Shared usage of a
broadband network
Multidrop lines
- more complex hardware
- simpler cabling system
O’Brien 191
Ring Networks
Ring Network
- more equal basis
O’Brien 147
Public data networks
PAD =
Packet Assembler
and Disassembler
Data Network
PAD
E.g..: DCS 1000 - 6000 char/sec , cost / volume data ( X25 )
Due to high connection cost ($ 30.000 year) usage of PAD
ISDN
ISDN
Integrated services
Digital network
ISDN
- universal network for telephone and data
- > 6000 char/sec
Communication
Systems
13th lecture
Chair of Communication Systems
Department of Applied Sciences
University of Freiburg
2008
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Textbook Overview
 Web site: http://www.wiley.com/college/englander
 Part 1 (Chapter 1)
 Computer system overview
 Part 2 (Chapters 2-5)
 Number systems and data formats
 Part 3 (Chapters 6-12)
 Computer architecture and hardware operation
 Part 4 (Chapters 13-18)
 Software – operating systems, applications, development
environments
 Part 5 (Supplementary Chapters 1-3)
 Digital logic, addressing modes, and communication channel
technology
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 Text books (german):
 Jochen Schiller, Mobilkommunikation
 Bernhard Walke, Mobilfunknetze und ihre Protokolle,
Grundlagen GSM, Universal Mobile
Telecommunications System (UMTS), ...
 Link (see seminar slides and papers):
 http://www.ks.unifreiburg.de/download/papers/telsemWS05/
UMTS-nextGeneration/UMTSSeminararbeit-Stefan%20Nagy.pdf
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End Of Sessions
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