By Omar Y. Tahboub

Multimedia and Networking Lab MediaNetComputer Science Department

Kent State University

Omar Y. Tahboub Department of Computer ScienceKent State UniversityKent, Ohio 44242 Office: (330)-672-7825Email: otahboub@cs.kent.eduURL: http://www.cs.kent.edu/~otahboub

Education

Ph.D. in Computer Science, Kent State University, 2010(expected)

M.S. in Computer Science, University of Jordan, 2004

B.S. in Computer Science, Jordan University of Science and Technology, 2002

Research Interests

Scheduling-based Routing in Predictable Intermittent Networks

Scheduling-based Routing in Disruptive/Delay Tolerant Networks

Internet2 Network Backbone Architectural Design

Internet2 Network Protocol Architectural Design

Dynamic Circuit Networking at MPLS Protocol (DCN@MPLS)

Design of Multi-Party Communication Architectures for Enterprise Space Explorations

Introduction

Part 1:Modern Information Systems: “The Big Picture”

Part 2: Introduction to Operating Systems

Summary

Introduction

Part 1:Modern Information Systems: “The Big Picture”◦ Reference Model◦ Architectural Model◦ Networking and Internet Evolution

Part 2: Operating Systems◦ Operating System (OS)◦ The Functions of OS◦ The Organization of OS◦ Types of OS ◦ Design Issues of OS

Summary

In this talk, we aim to achieve two main goals:1. Presentation of the “Big Picture” of modern

information systems.

2. Answer some interesting questions related to operating systems:

What are they? How they work? In what types they come? How do they evolve?

Introduction

Part 1:Modern Information Systems: “The Big Picture”◦ Components◦ Architecture◦ Interconnectivity

Part 2: Operating Systems

Summary

Information Systems (ISs) have become a central element in modern organizations.

Generally, ISs are studied in in terms of their:◦ Components◦ Architecture ◦ Interconnectivity

Introduction

Part 1:Modern Information Systems: “The Big Picture”◦ Reference Model◦ Architectural Model◦ Network and Internet Evolution

Part 2: Operating Systems

Summary

People Procedures Software Hardware Data

Procedures Software Hardware Data

People

Teacher/Students

Banker

Stock Broker

Operator

People Software Hardware Data

Procedures

Installation Manual

Software Training Kit

User Manual

People Procedures Hardware Data

Software

System Software

(Operating System)

Application Software

People Procedures Software Data

Hardware

Mouse

KeyboardTower

Monitor

Microcomputer

MinicomputerSupercomputer

People Procedures Software Hardware

Data

Text

Image

Video

Audio

Introduction

Part 1:Modern Information Systems: “The Big Picture”◦ Reference Model◦ Architectural Model◦ Networking and Internet Evolution

Part 2: Operating Systems

Summary

Information System Architectural Model

Local Area Network

Wide Area Network

The Internet

Modern ISs incorporate various types of computers scaling from handheld gadgets to supercomputers.

The software component represents a central component in modern ISs.

Further, system software (OS) forms a key element in the IS software component

Hence, it is the heart of the IS.

Introduction

Part 1:Modern Information Systems: “The Big Picture”

Part 2: Operating Systems◦ Operating System (OS)◦ The Functions of OS◦ The Organization of OS◦ Types of OS ◦ Design Issues of OS

Summary

Introduction

Part 1:Modern Information Systems: “The Big Picture”

Part 2: Operating Systems◦ Operating System (OS)◦ The Functions of OS◦ The Organization of OS◦ Types of OS ◦ Design Issues of OS

Summary

Operating systems are:◦ No universally accepted definition

◦ “Everything a vendor ships when you order an operating system” is good approximation But varies wildly

◦ “The one program running at all times on the computer” is the kernel. Everything else is either a system program (ships with the operating system) or an application program.

Operating systems is:◦ system software, which operates the computer hardware.

◦ A virtual machine shell, which provided a logical representation of the underlying physical computer hardware.

◦ An intermediary between a user of a computer and the computer hardware.

◦ A set of system and application and utility software that manage, allocate and coordinate the underlying hardware resources including: Processor (CPU) Graphic Processor (GPU) Memory Storage Network Communication

Introduction

Part 1:Modern Information Systems: “The Big Picture”

Part 2: Operating Systems◦ Operating System (OS)◦ The Functions of OS◦ The Organization of OS◦ Types of OS ◦ Design Issues of OS

Summary

Execute user programs and make solving user problems easier

Make the computer system convenient to use

Use the computer hardware in an efficient manner.

Introduction

Part 1:Modern Information Systems: “The Big Picture”

Part 2: Operating Systems◦ Operating System (OS)◦ The Functions of OS◦ The Organization of OS◦ Types of OS ◦ Design Issues of OS

Summary

Computer-system operation◦ One or more CPUs, device controllers connect

through common bus providing access to shared memory

◦ Concurrent execution of CPUs and devices competing for memory cycles

I/O devices and the CPU can execute concurrently

Each device controller is in charge of a particular device type

Each device controller has a local buffer

CPU moves data from/to main memory to/from local buffers

I/O is from the device to local buffer of controller

Device controller informs CPU that it has finished its operation by causing an interrupt

Introduction

Part 1:Modern Information Systems: “The Big Picture”

Part 2: Operating Systems◦ Operating System (OS)◦ The Functions of OS◦ The Organization of OS◦ Types of OS ◦ Design Issues of OS

Summary

Mainly there are five types of Operating Systems:1. Multi/Single-User Operating Systems2. Multi/Single-Tasking Operating Systems3. Real-Time Operating Systems4. Distributed Operating Systems5. Embedded Operating Systems

1. Multi/Single User Operating Systems:

◦ Allow multiple users to access a computer system concurrently.

◦ Time-sharing systems can be classified as multi-user systems.

◦ Single-user operating systems, are usable by a single user at a time.

◦ Multi-user operating systems

◦ Single-user operating systems

2. Multi/Single Tasking Operating Systems:

◦ Single Tasking: only one program is allowed to run at a time.

◦ Multi-Taking OS: Multi programs are allowed to run concurrently. Pre-emptive : OS slices CPU time and dedicate a

slice for each program.

Cooperative: relying on each process to give time to the other processes in a defined manner

3. Real-Time Operating Systems (RTOS):

◦ Multitasking operating system that aims at executing real-time applications.

◦ Quick and predictable response to events.

◦ Use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. Event-driven time-sharing design.

◦ ChibiOS/RT, BeRTOS and LynxOS

4. Distributed Operating Systems (DOS):

◦ Manages a group of independent computers and makes them appear to be a single computer.

◦ When computers in a group work in cooperation, they make a distributed system.

◦ Amoeba Operating System, and E1 DOS

5. Embedded Operating Systems :

◦ Used in embedded computer systems are known as embedded operating systems.

◦ Operate on small machines like PDAs with less autonomy.

◦ Operate with a limited number of resources.

◦ Windows CE, FreeBSD, and Minix 3.

Introduction

Part 1:Modern Information Systems: “The Big Picture”

Part 2: Operating Systems◦ Operating System (OS)◦ The Functions of OS◦ The Organization of OS◦ Types of OS ◦ Design Issues of OS

Summary

Development of faster and more robust hardware.

Demand for better performance coping with emerging hardware technologies.

Scalability.

Security.

Communication and Internet Evolution

Gave a brief demonstration of modern information systems highlighting operating systems.

Operating system forms the heart of an information system.

Gave a holistic introduction to operating systems answering a number interesting questions:◦ What are they?◦ What they do?◦ How they are organized?◦ What are their types?◦ What are the their design issues?