Introduction to Computers & Introduction to Computers & NetworkingNetworking

Introduction to ComputersIntroduction to Computers– HistoryHistory– Organization Organization – Operating SystemOperating System

Introduction to NetworkIntroduction to Network– LAN, MAN and WANLAN, MAN and WAN– Transmission Media, Network TopologiesTransmission Media, Network Topologies– Protocols & InternetProtocols & Internet

How to login on server and Unix commandsHow to login on server and Unix commands PINE software PINE software

– Email , file attachmentEmail , file attachment Servers at Servers at http://www.imtech.res.in/raghava/http://www.imtech.res.in/raghava/

History of Computing - History of Computing - Early ComputersEarly Computers

Abacus (ancient orient, still in use)Abacus (ancient orient, still in use) Slide rule (17C, John Napier)Slide rule (17C, John Napier) Adding machine with geared wheels (17C, B. Pascal)Adding machine with geared wheels (17C, B. Pascal) Difference Engine (19C, C. Babbage): First device using Difference Engine (19C, C. Babbage): First device using

the principles of modern computer.the principles of modern computer. ENIAC (1945, John Mauchly and J. Presper Eckert, Jr.)ENIAC (1945, John Mauchly and J. Presper Eckert, Jr.)

– Vacuum tube computer (18,000 electron tubes)Vacuum tube computer (18,000 electron tubes) Three important inventionsThree important inventions

– Stored program concept (John von Neumann)Stored program concept (John von Neumann)– Transistor (J. Bardeen, W.H. Brattain, W. Shockley)Transistor (J. Bardeen, W.H. Brattain, W. Shockley)– Magnetic core memory (J.W. Forrester and Magnetic core memory (J.W. Forrester and

colleagues in MIT)colleagues in MIT)

IBM 701 IBM 701 (Defense Calculator)(Defense Calculator) Addition time: 60 microsecondsAddition time: 60 microseconds Multiplication: 456 microsecondsMultiplication: 456 microseconds Memory: 2048 (36 bit) words using Memory: 2048 (36 bit) words using

Williams tubesWilliams tubes Secondary memory:Secondary memory:

– Magnetic drum: 8192 wordsMagnetic drum: 8192 words– Magnetic tape: plasticMagnetic tape: plastic

Delivered: Delivered: December 1952December 1952: IBM : IBM World Headquarters (total of 19 World Headquarters (total of 19 installed)installed)

Second Generation (1958-Second Generation (1958-1964)1964)

1958 Philco introduces TRANSAC S-20001958 Philco introduces TRANSAC S-2000– first transistorized commercial machinefirst transistorized commercial machine

IBM 7070, 7074 (1960), 7072(1961)IBM 7070, 7074 (1960), 7072(1961) 1959 IBM 7090, 7040 (1961), 7094 (1962)1959 IBM 7090, 7040 (1961), 7094 (1962) 1959 IBM 1401, 1410 (1960), 1440 (1962)1959 IBM 1401, 1410 (1960), 1440 (1962) FORTRAN, ALGOLFORTRAN, ALGOL, and , and COBOLCOBOL are first are first

standardized programming languagesstandardized programming languages

Third Generation (1964-1971)Third Generation (1964-1971)

April 1964 IBM announces the System/360April 1964 IBM announces the System/360– solid logic technology (integrated circuits)solid logic technology (integrated circuits)– family of “compatible” computersfamily of “compatible” computers

1964 Control Data delivers the CDC 66001964 Control Data delivers the CDC 6600 nanosecondsnanoseconds telecommunicationstelecommunications BASICBASIC, Beginners All-purpose Symbolic Instruction Code, Beginners All-purpose Symbolic Instruction Code

Fourth Generation (1971- )Fourth Generation (1971- )

Large scale integrated circuits (MSI, LSI)Large scale integrated circuits (MSI, LSI) Nanoseconds and picosecondsNanoseconds and picoseconds Databases (large)Databases (large) Structured languages (Structured languages (PascalPascal)) Structured techniquesStructured techniques Business packagesBusiness packages

Intel processorsIntel processors CPUCPU YearYear DataData MemoryMemory MIPSMIPS 40044004 19711971 44 1K1K 80088008 19721972 88 16K16K 80808080 19741974 88 64K64K 80888088 19801980 88 1M1M .33.33 8028680286 19821982 1616 1M1M 33 8038680386 19851985 3232 4G4G 1111 8048680486 19891989 3232 4G4G 4141 Pentium1993Pentium1993 6464 4G4G 111 111 Pentium I to IVPentium I to IV INTEL XeonINTEL Xeon INTEL IteniumINTEL Itenium INTEL Dual/Quodo/ExtremeINTEL Dual/Quodo/Extreme

Type of Computers Type of Computers Supercomputing: used for scientific computing Mainframes: used to be primary form of computer, used in

centralized computers, used in businesses for timesharing Servers: computers used to connect other computers to the

internet, printer, file sharing, etc. Desktops: Personal Computers Workstations: More powerful version of the personal

computer Handheld: Smaller operating Systems for handhelds Laptops/Notebook: Small portable computer Real Time: Operating Systems for information that needs to

be updated in real time Embedded Systems: Systems that are found within another

System

OrganizationOrganization

A computer system consists ofA computer system consists of– hardwarehardware– system programssystem programs– application programsapplication programs

Organization of ComputerOrganization of Computer

Input DevicesInput Devices– Keyboard; Mouse; Digitiger; Joystick; Punch card etc.Keyboard; Mouse; Digitiger; Joystick; Punch card etc.

Output DevicesOutput Devices– Monitors/Screens (MDA, MGA; CGA; EGA; VGA & Monitors/Screens (MDA, MGA; CGA; EGA; VGA &

SVGA) ; Printers; Plotters; LCD; LED etc. SVGA) ; Printers; Plotters; LCD; LED etc. Data StorageData Storage

– Primary Storage (RAM)Primary Storage (RAM)– Secondary Storage (floppy disk & hard disk)Secondary Storage (floppy disk & hard disk)

Central Processing UnitCentral Processing Unit Microprocessors (INTEL 8080, 8086, Microprocessors (INTEL 8080, 8086,

80286, 80386, 80486, Pentium I, II, III, IV)80286, 80386, 80486, Pentium I, II, III, IV)

OrganizationOrganization

Components of a simple personal computerComponents of a simple personal computer

Monitor

Bus

Concept and Implementation of Concept and Implementation of NetworkNetwork

Transmission Media & TechniquesTransmission Media & Techniques EthernetEthernet

– UTP (10base2) UTP (10base2) – Thick ethernet (10base5) Thick ethernet (10base5) – Thin Ethernet (10base2)Thin Ethernet (10base2)

Optical FiberOptical Fiber Network TopologiesNetwork Topologies

– Star (Easy services, One Device, Centralize cont.)Star (Easy services, One Device, Centralize cont.)– BUS (Short cable; Expandable; simplicity)BUS (Short cable; Expandable; simplicity)– RING (Short cable; suitable for optical Fibers)RING (Short cable; suitable for optical Fibers)– Hybrid (Tree topology; ring-star)Hybrid (Tree topology; ring-star)

Network TopologiesNetwork Topologies

Physical and Logical TopologiesPhysical and Logical Topologies TopologiesTopologies

– BusBus– RingRing– StarStar– Extended StarExtended Star– MeshMesh– HybridHybrid

Bus TopologyBus Topology

Bus TopologyBus Topology

Ring TopologyRing Topology

Star TopologyStar Topology

Extended Star TopologyExtended Star Topology

A Star Network

which has been

expanded to include an additional

hub or hubs.

Hybrid TopologyHybrid Topology

Communication Protocols Communication Protocols

TCP/IP TCP/IP Novel Net Novel Net Netbui (Windows Network) Netbui (Windows Network) Digital NetworkDigital Network InternetInternet

Concept of Proxy Server & FirewallsConcept of Proxy Server & Firewalls

Internet Service ProvidersInternet Service Providers Telephone LineTelephone Line

– ModemModem ISDN LineISDN Line Lease LineLease Line Proxy server IP AddressProxy server IP Address

– Port numberPort number

What Is the Internet?What Is the Internet? A network of networks, joining many government, A network of networks, joining many government,

university and private computers together and university and private computers together and providing an infrastructure for the use of E-mail, bulletin providing an infrastructure for the use of E-mail, bulletin boards, file archives, hypertext documents, databases boards, file archives, hypertext documents, databases and other computational resourcesand other computational resources

The vast collection of computer networks which form The vast collection of computer networks which form and act as a single huge network for transport of data and act as a single huge network for transport of data and messages across distances which can be anywhere and messages across distances which can be anywhere from the same office to anywhere in the world.from the same office to anywhere in the world.

Written by William F. Slater, III1996President of the Chicago Chapter of the Internet Society

Copyright 2002, William F. Slater, III, Chicago, IL, USA

Brief History of the Brief History of the InternetInternet

1968 - DARPA 1968 - DARPA (Defense Advanced Research Projects (Defense Advanced Research Projects

Agency) Agency) contracts with BBNcontracts with BBN (Bolt, Beranek & Newman) (Bolt, Beranek & Newman)

to create ARPAnetto create ARPAnet 1970 - First five nodes: 1970 - First five nodes:

– UCLAUCLA– StanfordStanford– UC Santa BarbaraUC Santa Barbara– U of Utah, and U of Utah, and – BBNBBN

1974 - TCP specification by Vint Cerf1974 - TCP specification by Vint Cerf 1984 – On January 1, the Internet with its 1000 1984 – On January 1, the Internet with its 1000

hosts converts en masse to using TCP/IP for its hosts converts en masse to using TCP/IP for its messagingmessaging

Internet Growth TrendsInternet Growth Trends 1977: 111 hosts on Internet1977: 111 hosts on Internet 1981: 213 hosts1981: 213 hosts 1983: 562 hosts1983: 562 hosts 1984: 1,000 hosts1984: 1,000 hosts 1986: 5,000 hosts1986: 5,000 hosts 1987: 10,000 hosts1987: 10,000 hosts 1989: 100,000 hosts1989: 100,000 hosts 1992: 1,000,000 hosts1992: 1,000,000 hosts 2001: 150 – 175 million hosts2001: 150 – 175 million hosts 2002: over 200 million hosts2002: over 200 million hosts By 2010, about 80% of the planet will be on the Internet By 2010, about 80% of the planet will be on the Internet

TCP/IP AddressesTCP/IP Addresses Every host on the Internet must have a Every host on the Internet must have a

unique IP addressunique IP address The IP address is a 32-bit number which The IP address is a 32-bit number which

we write in dotted decimal notationwe write in dotted decimal notation The first part of the IP address is the The first part of the IP address is the

network address – the remainder is the network address – the remainder is the host IDhost ID

A subnet mask is used to determine the A subnet mask is used to determine the network address from a IP host addressnetwork address from a IP host address

All hosts on the same network are All hosts on the same network are configured with the same subnet maskconfigured with the same subnet mask

Internet Applications: Internet Applications: Port AssignmentsPort Assignments

2121 FTP (sftp) FTP (sftp) : File Transfer: File Transfer 23 Telnet (ssh) 23 Telnet (ssh) : Remote login: Remote login 25 smtp (mail) 25 smtp (mail) : Email transfer: Email transfer 70 gopher 70 gopher : Browser: Browser 79 finger 79 finger : Checking network: Checking network PING PING : Network : Network

diagnosticdiagnostic 80 HTTP80 HTTP : Web browsing: Web browsing

History of Operating History of Operating Systems (1)Systems (1)

Early batch systemEarly batch system– bring cards to 1401bring cards to 1401– read cards to taperead cards to tape– put tape on 7094 which does computingput tape on 7094 which does computing– put tape on 1401 which prints outputput tape on 1401 which prints output

Operating SystemsOperating Systems

Single UserSingle User– a) CP/M ; a) CP/M ; – b) MS-DOS; b) MS-DOS; – c) Macintosh; c) Macintosh; – d) Windowsd) Windows

Multiple UserMultiple User– UNIX (1969 by Ken Thompson; C; Bell)UNIX (1969 by Ken Thompson; C; Bell)– LinuxLinux– SolarisSolaris– IRIXIRIX– VMS (Digital)VMS (Digital)

What is Unix?What is Unix?

A fully featured modern operating system A fully featured modern operating system

It is available in a variety of “flavors.” It is available in a variety of “flavors.”

It’s comprised of simple tools that perform a It’s comprised of simple tools that perform a single function well.single function well.

These tools can be used together to perform These tools can be used together to perform complex tasks.complex tasks.

Using Other CommandsUsing Other Commands Syntax: Syntax: commandcommand filefile

catcat Echos file contents to the screenEchos file contents to the screen grepgrep Searches a file for a stringSearches a file for a string

moremore Echos a file a line at a timeEchos a file a line at a time

lessless Same as more but more featuresSame as more but more features

wcwc Counts the words in a file and moreCounts the words in a file and more

sortsort Sorts the contents of a fileSorts the contents of a file

Other File System Utilities Other File System Utilities

lsls Lists all files in a directoryLists all files in a directory

cpcp Copies filesCopies files

mvmv Moves filesMoves files

rmrm Deletes filesDeletes files

mkdirmkdir Makes directoriesMakes directories

rmdirrmdir Removes directories Removes directories