Download Network Topologies

Introduction to Computers & Networking
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Introduction to Computers
– History
– Organization
– Operating System
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Introduction to Network
– LAN, MAN and WAN
– Transmission Media, Network Topologies
– Protocols & Internet
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How to login on server and Unix commands
PINE software
– Email , file attachment
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Servers at http://www.imtech.res.in/raghava/
History of Computing - Early
Computers
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Abacus (ancient orient, still in use)
Slide rule (17C, John Napier)
Adding machine with geared wheels (17C, B. Pascal)
Difference Engine (19C, C. Babbage): First device using the
principles of modern computer.
ENIAC (1945, John Mauchly and J. Presper Eckert, Jr.)
– Vacuum tube computer (18,000 electron tubes)
Three important inventions
– Stored program concept (John von Neumann)
– Transistor (J. Bardeen, W.H. Brattain, W. Shockley)
– Magnetic core memory (J.W. Forrester and colleagues in
MIT)
IBM 701 (Defense Calculator)
Addition time: 60 microseconds
 Multiplication: 456 microseconds
 Memory: 2048 (36 bit) words using
Williams tubes
 Secondary memory:
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– Magnetic drum: 8192 words
– Magnetic tape: plastic
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Delivered: December 1952: IBM World
Headquarters (total of 19 installed)
Second Generation (1958-1964)
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1958 Philco introduces TRANSAC S-2000
– first transistorized commercial machine
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IBM 7070, 7074 (1960), 7072(1961)
1959 IBM 7090, 7040 (1961), 7094 (1962)
1959 IBM 1401, 1410 (1960), 1440 (1962)
FORTRAN, ALGOL, and COBOL are first standardized
programming languages
Third Generation (1964-1971)
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April 1964 IBM announces the System/360
– solid logic technology (integrated circuits)
– family of “compatible” computers
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1964 Control Data delivers the CDC 6600
nanoseconds
telecommunications
BASIC, Beginners All-purpose Symbolic Instruction Code
Fourth Generation (1971- )
Large scale integrated circuits (MSI, LSI)
 Nanoseconds and picoseconds
 Databases (large)
 Structured languages (Pascal)
 Structured techniques
 Business packages
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Intel processors
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CPUYear
Data Memory
4004
1971
4
8008
1972
8
8080
1974
8
8088
1980
8
80286
1982
16
80386
1985
32
80486
1989
32
Pentium1993
64
Pentium I to IV
INTEL Xeon
INTEL Itenium
INTEL Dual/Quodo/Extreme
1K
16K
64K
1M
1M
4G
4G
4G
MIPS
.33
3
11
41
111
Type of Computers
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Supercomputing: used for scientific computing
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Mainframes: used to be primary form of computer, used in
centralized computers, used in businesses for timesharing
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Servers: computers used to connect other computers to the internet,
printer, file sharing, etc.
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Desktops: Personal Computers
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Workstations: More powerful version of the personal computer
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Handheld: Smaller operating Systems for handhelds
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Laptops/Notebook: Small portable computer
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Real Time: Operating Systems for information that needs to be
updated in real time
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Embedded Systems: Systems that are found within another System
Organization
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A computer system consists of
– hardware
– system programs
– application programs
Organization of Computer
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Input Devices
– Keyboard; Mouse; Digitiger; Joystick; Punch card etc.
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Output Devices
– Monitors/Screens (MDA, MGA; CGA; EGA; VGA & SVGA) ;
Printers; Plotters; LCD; LED etc.
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Data Storage
– Primary Storage (RAM)
– Secondary Storage (floppy disk & hard disk)
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Central Processing Unit
Microprocessors (INTEL 8080, 8086, 80286,
80386, 80486, Pentium I, II, III, IV)
Organization
Monitor
Bus
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Components of a simple personal computer
Concept and Implementation of Network
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Transmission Media & Techniques
Ethernet
– UTP (10base2)
– Thick ethernet (10base5)
– Thin Ethernet (10base2)
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Optical Fiber
Network Topologies
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Star (Easy services, One Device, Centralize cont.)
BUS (Short cable; Expandable; simplicity)
RING (Short cable; suitable for optical Fibers)
Hybrid (Tree topology; ring-star)
Network Topologies
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Physical and Logical Topologies
Topologies
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Bus
Ring
Star
Extended Star
Mesh
Hybrid
Bus Topology
Bus Topology
Ring Topology
Star Topology
Extended Star Topology
A Star
Network
which has
been
expanded to
include an
additional
hub or hubs.
Hybrid Topology
Communication Protocols
TCP/IP
 Novel Net
 Netbui (Windows Network)
 Digital Network
 Internet
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Concept of Proxy Server & Firewalls
Internet Service Providers
 Telephone Line
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– Modem
ISDN Line
 Lease Line
 Proxy server IP Address
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– Port number
What Is the Internet?
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A network of networks, joining many government, university
and private computers together and providing an infrastructure
for the use of E-mail, bulletin boards, file archives, hypertext
documents, databases and other computational resources
The vast collection of computer networks which form and act as
a single huge network for transport of data and messages
across distances which can be anywhere from the same office to
anywhere in the world.
Written by William F. Slater, III
1996
President of the Chicago Chapter of the Internet Society
Copyright 2002, William F. Slater, III, Chicago, IL, USA
Brief History of the Internet
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1968 - DARPA (Defense Advanced Research Projects Agency)
contracts with BBN (Bolt, Beranek & Newman) to create
ARPAnet
1970 - First five nodes:
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UCLA
Stanford
UC Santa Barbara
U of Utah, and
BBN
1974 - TCP specification by Vint Cerf
1984 – On January 1, the Internet with its 1000
hosts converts en masse to using TCP/IP for its
messaging
Internet Growth Trends
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1977: 111 hosts on Internet
1981: 213 hosts
1983: 562 hosts
1984: 1,000 hosts
1986: 5,000 hosts
1987: 10,000 hosts
1989: 100,000 hosts
1992: 1,000,000 hosts
2001: 150 – 175 million hosts
2002: over 200 million hosts
By 2010, about 80% of the planet will be on the Internet
TCP/IP Addresses
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Every host on the Internet must have a unique
IP address
The IP address is a 32-bit number which we
write in dotted decimal notation
The first part of the IP address is the network
address – the remainder is the host ID
A subnet mask is used to determine the network
address from a IP host address
All hosts on the same network are configured
with the same subnet mask
Internet Applications: Port
Assignments
21 FTP (sftp)
 23 Telnet (ssh)
 25 smtp (mail)
 70 gopher
 79 finger
 PING
 80 HTTP
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:
:
:
:
:
:
:
File Transfer
Remote login
Email transfer
Browser
Checking network
Network diagnostic
Web browsing
History of Operating Systems
(1)
Early batch system
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bring cards to 1401
read cards to tape
put tape on 7094 which does computing
put tape on 1401 which prints output
Operating Systems
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Single User
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a) CP/M ;
b) MS-DOS;
c) Macintosh;
d) Windows
Multiple User
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UNIX (1969 by Ken Thompson; C; Bell)
Linux
Solaris
IRIX
VMS (Digital)
What is Unix?
A fully featured modern operating system
It is available in a variety of “flavors.”
It’s comprised of simple tools that perform a
single function well.
These tools can be used together to perform
complex tasks.
Using Other Commands
Syntax: command file
cat
 grep
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Echos file contents to the screen
Searches a file for a string
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more
Echos a file a line at a time
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less
Same as more but more features
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wc
Counts the words in a file and more
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sort
Sorts the contents of a file
Other File System Utilities
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ls
Lists all files in a directory
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cp
Copies files
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mv
Moves files
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rm
Deletes files
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mkdir
Makes directories
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rmdir
Removes directories