Introduction to Operating Systems

Part I: Operating Systems OverviewPart II: Operating Systems in Practice (focusing on Windows and Linux)

PLEASE MAKE COPIES OF LINSPIRE LIVE-CD FOR LAB PRACTICE THIS WEEK

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Early Computers• Charles Babbage (1791-1871) designed the

first true digital computer called the analytical engine.

• That was purely mechanical and intended to do math operations

• The engine was supposed to be made of brass, and steam powered

• He did not actually built the machine but inspired others in the field.

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Early Computers

• Babbage also thought of the concept of software

• And hired the first programmer (Lady Ada, Countess of Lovelace) for his analytical machine

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Current Computer Systems

• A computer system consists of– hardware– system programs– application programs

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What is an Operating System• It is the software that enables us to use the hardware• It is a resource manager– Allocates system resources such as I/O devices, CPU etc– Schedules different jobs etc

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History of Operating Systems

• First generation 1945 - 1955– vacuum tubes, plug boards– Still very slow and used for scientific calculations

• No OS was needed• Programs were entered by setting some switches

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History of Operating Systems• Second generation 1955 – 1965

– transistors, batch systems– Universities started to buy computers (spending millions of

dollars)– Punched cards were used– To run a job (a program or a set of related programs) first punch it

and give the deck to the operators and wait for the output (batch operation)

– Computers were single user

IBM STRETCH DEC

PDP-1

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Third generation 1965 – 1980– Integrated Circuits

– Engineer at the Advanced Computing Systems Division of IBM, 1968, commenting on the microchip

– "But what ... is it good for?"

History of Operating Systems

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Famous Remarks

• "I have traveled the length and breadth of this country and talked with the best people, and I can assure you that data processing is a fad that won't last out the year.“– The editor in charge of business books for Prentice Hall -

1957

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History of Operating Systems

• Multiprogramming system – three jobs in memory – 3rd generation

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The concept of spooling was introduced by 3rd generation operating systemsand a memory partition was available, it is loaded directly to memory.

Third generation OSs were still not interactive, i.e., whenever there is an error, programmers would realize it after a couple of hours.

This problem lead to timesharing systems where the user has an online terminal

History of Operating Systems

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History of Operating Systems• Tanenbaum wrote a version of UNIX called MINIX

with POSIX support for educational use.

• A Finnish student Linus Torvalds wrote a free production of MINIX called Linux

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History of Operating Systems• Fourth generation 1980 – present– Personal computers were developed after LSI (Large Scale Integration) circuits were invented.– First Microcomputer:• Intel 8080 CPU + attached 8-inch floppy disk• First disk based OS CP/M (Control Program for Microcomputers)

– In 1980s IBM designed the IBM PC and contacted Bill Gates for an operating System

Understanding Operating Systems

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Brief History of Operating Systems Development

1940 1955 1965 1980 1990

First Generation

Vacuum tube, single user, early operating systems

Second Generation

Job scheduling, JCL, faster I/O, spooling, batch, files

Third Generation

Shared processing, multiprogramming, virtual memory, DBMS

Recent Developments

Distributed computing, personal computers, high-

speed communication, multi-media

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Famous Remark

• “There is no reason anyone would want a computer in their home.“– Ken Olson, president, chairman and founder of Digital Equipment

Corp. - 1977

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History of Operating Systems• Bill Gates suggested IBM that they should look at CP/M (one of

the the most successful OS for microcomputers at that time, by Gary Kildall)

• The biggest mistake of all:

– Kindall refused to sign a non-disclosure agreement

• IBM went back to Bill Gates and signed a contract with him to write an OS for their new home computer

• MS-DOS was based on QDOS, the "Quick and Dirty Operating System" written by Tim Paterson of Seattle Computer Products,

• QDOS was based on Gary Kildall's CP/M

• Microsoft bought the rights to QDOS for $50,000

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Famous Remark

• "I think there is a world market for maybe five computers." – Thomas Watson, chairman of IBM - 1943

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History of Operating Systems

• Early MS-DOS was very primitive but later versions included advanced features taken from UNIX

• The early OS for microcomputers were based on users typing in commands from the keyboard

• Doug Engelbart from SRI invented the Graphical User Interface (GUI) with windows, icons, menus, and mouse.

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History of Operating Systems

• Steve Jobs saw the value of GUI in a PC and developed the Apple computer with GUI (Apple Macintosh) in his garage.

• He is also the co-founder of Pixar which has created very successful animated films: Toy Story ; A Bug's Life; Toy Story 2; Finding Nemo; Monsters.

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Yet another Famous Remarks!

• "640K ought to be enough for anybody." – Bill Gates, 1981

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History of Operating Systems• Microsoft developed a GUI-based system called Windows which

originally ran on top of MS-DOS (just as a GUI to DOS)

• Windows 95 and 98 were real GUI based operating systems still based on 16 bit Intel assembly language

• Windows NT is 32-bit rewrite from scratch version of Windows 98.

• Windows 2000 (Windows NT version 5.0), Windows Me.

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History of Computinghttp://www.computerhistory.org/

• Hewlett Packard was founded in 1939 by David Packard and Bill Hewlett,

• Their first product, the HP 200A Audio Oscillator

• Walt Disney Pictures ordered eight of the 200B model to use during the creation of the movie “Fantasia.”

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History of Computing http://www.computerhistory.org/

Computer wars:

Germany vs Britain

Alan Turing: The bombe

Understanding Operating Systems 24

Overview of Operating Systems

• Introduction• Operating System

Components• Machine Hardware• Types of Operating Systems• Brief Introduction of OS

Development – focusing on Linux (because we’re already familiar with Windows

• Linux vs Windows• The implications of of Linux

in education

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Components of an Operating System

Operating system – part of the computing system that manages all of the hardware and all of the software– Controls every file, device, section of main memory &

every nanosecond of processing time

• Memory manager• Processor manager • Device manager• File manager

Operating system consists of

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Subsystems Must Work With Each Other

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Tasks Performed by Each Subsystem

1. Monitor its resources continuously

2. Enforce the policies that determine who gets what, when and how much

3. Allocate the resource when appropriate

4. Deallocate the resource (reclaim it) when appropriate

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Machine Hardware

• Memory chips

• Input/output devices (monitor, keyboard, printer)

• Storage devices (disks, magnetic tape, card readers, drums)

• Central Processing Unit (Arithmetic Logic Unit, registers, internal control, bus control)

Windows XP

Windows Vista• Win release after XP (Oct 01

2006)• Desktop only release• Originally 2004, now 2006• WinFS (NTFS add-on) OUT• Avalon 3D GUI layer, XML-

based• Based on .NET APIs WinFX• Digital Rights Restrictions

Windows Vista

MacOS X (Refer to Introduction to MAC OS downloadable from http//:zaipul.wikispaces.com)

Introduction to Linux

What we will cover• Why Linux?• What is Linux?• Myths of Linux• Example GUIs &

app's• Summary

Origins of Linux• Began as student Project by Linus Torvalds

Opened up to the world, now backed by big business

• Scientific cooperation model

• Open source implications Better security, anyone can improve, open to all, improved competition, cheaper, faster

• Matured over 14 yearsWinXP (3-12 years), Solaris 2 (15yrs), MAC OS (26 years)

Linux kernel• Linus Torvalds in 1991• Based on Minix kernel• Linux kernel works with

GNU components• Allow commercial

redistribution (GPLv2)

GNU Project (GNU’s Not Unix)

• Linux truly began from the inspiration of a brilliant man Richard Stallman in 1983.

• To develop Unix-like OS

composed entirely of free software (GNU GPLv1)

What is Linux ?• UNIX-like operating system

• Comprised– System utilities– LibrariesFrom GNU ProjectSometimes called GNU Linux

• Supported by: IBM, Sun, Novell, Microsoft,…

What is Linux?

Kernel + cmds/libs + apps + installer = a DISTRO

Well-known distros• Slackware• Debian• Redhat, Fedora• SuSE (drived from Slackware)• Ubuntu (drived from Debian)• Knoppix• Linspire (drived from Debian)

Distros

• Business

• Embedded

• Webserver

• Home Desktop!

Why Choose Linux?• Stability . Since Linux is based on the stable UNIX operating system, it inherits that stability

and reliability. Our Linux servers have uptimes in the MONTHS. • Linux is open-source, which means the source code is readily available to anyone who

wants it. Since the source code available, thousands of developers all over the world are able to contribute and improve Linux. As a result, security patches and new drivers come out quickly, sometimes in less than a day. This insures a very stable operating system and high uptime for your network operations.

• Affordability . You can download Linux software for free from the Internet at Real Time Enterprises´ local mirror or CDs can be purchased from distribution vendors for as little as $40.

• Linux can run on PC-based hardware. This means it´s easy to add disk space or memory. AND, some services will run very well on a P1 with 64MB RAM, which you probably have collecting dust at your office.

• Speed . Many studies have proven that on equal hardware, Linux is several times faster than Windows NT. In our own experience a Linux fileserver running Samba was at least 10 times faster than a Windows NT server and the NT server had faster, better hardware!

• Linux uses Linux uses a graphical user interfacea graphical user interface that is similar tothat is similar to other proprietary operating systems. other proprietary operating systems. (example: Microsoft XP or Mac OSX) (example: Microsoft XP or Mac OSX)

Growth to today

• 1996 KDE desktop environment• 1997 GNOME• 1998 Netscape source code, Mozilla Firefox• 2000 StarOffice by Sun, then OpenOffice.org

And now and future

• 25% server, 2.8% desktop (IDC, 2004)

• Expected $38 billion in 2008

Philosophy of Linux• Free software and open source• Freedom to use without restrictions• Freedom to study software and its source code• Freedom to modifyo redistribute under certain conditions• Interoperability (with other OSs)• Portability (on various architectures)• Community• Commercialization

Linux distributions (distro)

• To collect separate softwares, including:– Boot loader– Linux kernel– GNU libraries and tools– Command-line shells– Graphical X Window System– Desktop environment– Application software packages

Sweet Spot Linux Use

• Supercomputer clusters• Web servers• Firewalls, routers, caches• File servers• Mail servers• PDA, cell phones• Embedded real time (gas pumps, Tivo etc)

Linux Myths

• Zero cost

• Difficult to learn

• Only for servers

• Less secure than Windows

• Invulnerably secure

• Always suitable

Myths debunked✗ Without cost

A few distros free, most are commercial. Support is important

✗ Difficult to learn

Linspire is easy for anyone to learn & use

✗ Only for servers

Linspire well-proven on laptops, desktops

✗ Less secure than Windows

Linux has secure alternatives to IE, Outlook, and the registry – 3 of the buggiest virus propagators around. Still should follow good security practices

✗ Always suitable

Works very well for surfing/email/Word

Requirements for a Desktop Linux

• Compatible with your data

• Popular applications• Secure• Easy to use• Plays all media• Paid support• Reasonably priced• Easy to install

What is Linspire?What is Linspire?

Linspire facts:●Linux distro focusing exclusively on the Desktop●85-person company; HQ in San Diego, CA●Offices & partner-offices worldwide (Japan, Europe,

Mexico, South America, Australia)●Formed 4 years ago

Mission statement:●“To provide the world's easiest-to-use affordable personal computing solutions.”

Press Comments on Linspire

Worldwide Linspire “Light-ups”

Linspire

Linspire applications

• Email• Web browser • Office suite

• DVD playing• Cd burning• Image editing• Photos, MP3s, etc

Popular Linux Apps

• Lsongs Music Manager - Rip your favorite music, organize it, play it, sync it to portable music players, and burn

• Lphoto Photo Manager - Download, organize, edit, save, and share your entire photo collection.

• Nvu Web Authoring - Create web pages and manage their web site with no technical expertise or knowledge of HTML

• And more!

Office Suite

You don’t need to spend more for a complete office solution. Linspire comes with an Office Suite, included.

• Word processing

• Spreadsheets

• Presentations

Compatibility - 100% compatible with other suites including MS Office and Corel Wordperfect.

Demo Microsoft PPT and .doc file.

.doc

.xls

.ppt

What is the Click N' Run Service?

• CNR means “Click and Run”

• Online software warehouse with more than 2,000 Linux programs

• Easy, one-click installation• Automatic updates for

your software and PC

The 3 Big Wins of Linspire Linux

• Desktop focus, with commercial support

• Click N'Run Service for easy apps install

• Superb customer forums

http://forum.linspire.com

Next steps

• Live CD

• zero-effort experiment

• demo boot

• Try Linspire!http://tinyurl.com/9ax45

http://afu.com/

Linux vs. Windows

LinuxLinux WindowsWindows

Linux has different versions, depending on which vendor develops and runs it. Linux vendors include: Linspire, Linspire, Red HatRed Hat, , SuSESuSE, Ubuntu, Mandriva, , Ubuntu, Mandriva, Knoppix, Knoppix, SlackwareSlackware, , Caldera, DebianCaldera, Debian

Windows has different versions. It started with Win3.x, Win9x, WinME, WinNT, Win2000, WinXP. It is a proprietary software produced by Microsoft.

LinuxLinuxCost

WindowsWindowsCostCost

Linux is cheap or free to run. It can be downloaded from various Linux vendors.

Linux may run off a server so numerous computers may have access to the program.

Windows is expensive to run. The price to purchase a full version of Windows XP Professional is about USD400. Only one copy of Windows may be used on a computer. Activation with Microsoft is needed.

LinuxLinuxCost

WindowsWindowsCostCost

Linux is an open source software. Source codes are freely distributed to the public, of which programmers had reviewed to improve performance, eliminate bugs and strengthen security.

Windows is a proprietary closed source software. Codes are not released to the public.

LinuxLinuxOS Stability

WindowsWindowsOS OS Stability

When properly configured, Linux will run until the hardware fails or if the system is shut down. Linux claims that it may continuously run up to more than a year without freezing or shutting down. It is not as prone to bugs and viruses as most are geared towards Windows.

It is known to crash easily, and be infected by bugs and viruses. .

LinuxLinux Technical Support

WindowsWindowsTechnical Support

As source codes are easily accessible, solving technical problems are effective and efficient. Linux users rely on installation guides, or Linux forums to receive advice and suggestions from other users on technical problems. Very few businesses have trained staff to solve Linux bugs.

Proprietary software requires technicians to rely on Microsoft for technical information to fix bugs and problems. Numerous businesses have on site technicians that are Microsoft Certified Professionals.

There is a catch.

• Any modifications made to any programs must be Any modifications made to any programs must be released to the public. This is known as “Copyleft”released to the public. This is known as “Copyleft”

• According to Richard Stallman, software developers According to Richard Stallman, software developers have the right to make changes, share codes, use have the right to make changes, share codes, use and redistribute, but are not and redistribute, but are not bound to give away any bound to give away any derived work.derived work.

Installation, Installation, technical technical supportsupport

Transition Transition PeriodPeriod

SoftwareSoftwareapplicabilityapplicability

SoftwareSoftwarerequirementrequirement

HardwareHardwarerequirementrequirement

CostCost

Linux Linux and and

EducationEducation

The positive and negative implications of Linux on Education.

Linux and EducationLinux and Education

Problem/Question Possible Solution Expensive to purchase proprietary software licenses.

Linux can be obtained for free or at a low cost.

Expensive to upgrade proprietary software.

Software upgrades or modifications to programs are offered to the public at no cost.

Edu. Inst. have a tight technology budget and are limited to the number of licenses they can purchase. As a result, not all systems in a lab will run the same kinds of programs.

Linux runs on a server.Linux runs on a server.

Linux and EducationCost

Linux and Education Hardware Requirement

Problem/Question Possible Solution Due to budget constraint, many schools still run on 486, Pentium I, II, III. This is evident in many inner-city schools where the communities cannot afford to upgrade technology. Expensive to upgrade hardware for proprietary software.They are slow, and incompatible with the new versions of Windows or other current software applications that require more RAM.

Linux runs on networked servers and so may continue to use the 486, Pentium I, II, III.The community can also donate their old systems to their neighborhood school. Linux runs on minimal hardware requirements. Linux forums recommend that the minimal system requirements to function with decent performance is Pentium III, 128MB memory, 3Gb hard drive space, and bootable CD drive.

Linux and EducationSoftware Requirement

Problem/Question Possible Solution Expensive to purchase proprietary software licenses.

Linux can be obtained for free or at a low cost.

Expensive to upgrade proprietary software.

Software upgrades or modifications to programs are offered to the public at no cost. Old systems without graphical interface and minimum applications will not be compatible with recent Linux versions.

Edu. Inst. have a tight technology budget and are limited to the number of licenses they can purchase. As a result, not all systems in a lab will run the same kinds of programs.

Linux runs on a server and Linux runs on a server and computers can be networked to computers can be networked to all run on the same programs.all run on the same programs.

Linux and EducationSoftware Applicability

Problem/Question Possible Solution Many Edu. Inst. had spent millions of dollars in purchasing software licenses. This includes Windows, Microsoft Office and Educational games. If the movement of Linux is successful, the investment of these licenses are non-refundable.

There are Linux software programs similar to the function of Windows Microsoft. This includes Open Office, Star Office, KOffice.

In the future, when the student needs to use Windows in the workforce, and not Linux-they would lack the knowledge and training.

No Solution Very few game editors publish Linux versions of their games. Schools will have no choice other than to stay with Windows.

Linux and EducationInstallation and Technical Support

Problem/Question Possible Solution As the majority of Edu. Inst. owned computers do not run on Linux, they lack on-site trained and experienced technicians to install and provide technical support. There is already a shortage of technicians hired by the school board due to budget constraint.

Design professional-development workshops to train existing and new technicians with Linux, as well as teach teachers so they may educate their students in return. It takes fewer people to manage the Linux machines than Windows machines.

Linux and EducationTransition Period

Problem/Question Possible Solution Windows and Linux operating system do not work similarly. Users need to invest time to adapt to the change in OS.

Some Windows applications may run on Linux, when an emulator is used. A common emulator is called Wine. Install Windows and Linux on the same computer, which may act as an easier transition for beginners or those who are fans of both OS.