1. Introduction to CS447 Department of Computer Science Southern Illinois University Edwardsville Fall, 2015 Dr. Hiroshi Fujinoki E-mail: hfujino@siue.edu CS447 - Networks and Data Communications Introduction/000

2. CS447 - Networks and Data Communications Introduction/001 Agenda Types of networks this course will deal with Topics this course will discuss What this course is about What this course is NOT about Programming projects expected in this course

3. Applications (application software) System Software CS447 - Networks and Data Communications Introduction/002 Topics this course will discuss Three logical layers in computer networks Hardware E-mail Web-browser Streaming audio/video On-line banking Telephony Game Routers Cables Switches Modems Ethernet adapters Wireless transmitters Routing protocols HTTP TCP IP FTP UDP SSL Error control Flow control Compression Routing algorithms Computer Management Information System Electrical Engineering Computer Science The areas this course (CS447) will deal with Protocols Algorithms Algorithms = design/logics Protocols = implementation

4. CS447 - Networks and Data Communications Introduction/003 Types of networks this course will deal with Circuit-Switching Networks Packet-Switching Networks - Before you start transmission, you need to reserve network resources - You hold the resources until you complete your transmission - You can start transmission any time - Network resources are shared - Telephone networks - Internet Communication Networks - Data is transmitted as a stream of signals - Data is transmitted by packets

5. CS447 - Networks and Data Communications Introduction/004 Analog Switch Analog Signal Circuit-Switching Networks Example: Public telephone networks

6. CS447 - Networks and Data Communications Introduction/005 Example: Public telephone networks Circuit-Switching Networks Analog Switch Analog Signal

7. CS447 - Networks and Data Communications Introduction/006 Digital Switch Analog Signal 010 100 111 010 100 111 010 100 111 010 100 111010100 010100111 Analog Signal 010100111 Digitized data Sender PCReceiver PC Packet-Switching Networks Example: Internet

8. CS447 - Networks and Data Communications Introduction/007 Types of networks this course will deal with Circuit-Switching Networks Packet-Switching Networks - Before you start transmission, you need to reserve network resources - You hold the resources until you complete your transmission - You can start transmission any time - Network resources are shared - Telephone networks - Internet Communication Networks - Data is transmitted as a stream of signals - Data is transmitted by packets This course will mainly discuss packet-switching networks

9. CS447 - Networks and Data Communications Introduction/008 What this course is about 1. Understanding major components in computer networks 2. Understanding how the network hardware and software components work 3. Understanding how to make sure the things work as expected 4. Understanding fundamental network programming skills

10. CS447 - Networks and Data Communications Introduction/009 1. Understanding components in computer networks - What are the major network hardware components? - What are the major network software components? Data transmitting devices (NICs) Switching devices (Repeaters, Hubs, Switches and Routers) Network Cables (Copper wire, Optical fiber) Data transmission protocols Network application software Various data transmission and routing algorithms

11. CS447 - Networks and Data Communications Introduction/010 2. Understanding how the network hardware and software components work Design Concepts Implementation 3. Understanding how to make sure the things work as expected Performance Evaluation Performance Prediction - What are the purposes of the network system software? - How are the network system software designed? - How can we (our network application software) develop the system software or network application programs? - We cover this by programming assignments - How can we measure the performance of the system software? - How can we predict the performance?

12. CS447 - Networks and Data Communications Introduction/011 4. Understanding fundamental network programming skills Almost all network applications that use TCP/IP depend on “socket interface” to perform any network activity. Socket interface is provided as a set of functions (a. k. a., “API”) that application programs can call to perform network activities Each platform has its own socket interface = “winsock” library Windows UNIX/LINUX = socket library Have syntax-level compatibility - You can develop any network application using socket Most of the high-level programming languages have socket library included in it

13. CS447 - Networks and Data Communications Introduction/012 Understanding components in computer networks (lectures and quizzes) Design Concepts Performance Evaluation and Prediction Weight for subjects Implementation (programming assignments)

14. CS447 - Networks and Data Communications Introduction/013 What this course is NOT about Learning products from particular software/hardware venders - Learn DreamWeaver for developing web home pages - Learn how to set up routers from particular manufactures - Learn how to make a home page using HTML, PHP, MS ASP, etc. Preparing for particular network certificate - Understanding topics in this course will provide a foundation for those certificate After all, this course is never meant for particular network products Not for anything that does not require understanding of working of underlying networks

15. CS447 - Networks and Data Communications Programming projects expected in this course Application Layer System Software Layer Hardware Layer E-mail Streaming Audio/Video Game Telephony Tele-Conferencing Hardware (Network Adapter) TCP IP Socket Interface (as function calls) Device Drivers WWW Introduction/014 What programming project covers

16. CS447 - Networks and Data Communications Introduction/015 Definitions for academic dishonesty Can we do this? 1. Get a source code from somebody’s website and modify it. 2. Get a source code from a friend and modify it. 3. Work with your friend and create a source code. Then modify it. 4. Get source code given by a professor in another course and modify it. 5. Study example source code from a book and develop your own (instead of copying it).  Only “function-level” copy is allowed (up to 5 to 6 lines in the entire work)  Source must be mentioned  NO  YES