1. Computer Networks Sanjeewa HMC B.Sc(Hons(Ruh)) Reading MIT(Col) sanjihmc@yahoo.com

2. Objectives Brief introduction to computer networks & understanding sub netting to utilize ip address block in efficient manner.

3. Out lines What is a computer network? Components of a network. Advantages of a computer network. IP Sub netting IP address Subnet mask Purposes of sub netting Example for sub netting References

4. What is a computer network? A computer network is a set of interconnected network devices that allows them to share data, information, software, hardware devices and processing power.

5. Components of a network Server – to provide services Ex: file servers, web servers, data base servers Client - to get services from those servers. Ex: web client Protocols - A protocol is an agreement (rules) between the communicating parties on how communication is proceed. Ex: TCP/IP suite Transmission media – to transfer data between two network devices.

6. Transmission Media Guided Media Unguided Media

7. Guided media Physically connect two devices using wired connection. Ex: Twisted Pair (UTP,STP) Coaxial cable Optical fiber

8. Unguided Media Physically not connected using wired connection. use wireless technology to communicate with each other. Ex: wi-fi Infra red

9. Advantages of computer netwoks Provides a way to share data, programs, computing power and information. Online credit card checking, e-commerce and Electronic fund transfer are possible. Easily administered. Provides an efficient means of communication such as e-mail, voice mail, and video conferencing. Provides data security.

10. IP sub netting IP address Is a unique address (number) to identify each network devices. Is 32 bit binary number with 4 octal Ex:192.168.2.4 There is two parts in an ip address Network part Host part

11. IP sub netting cont……. IP Classes Class A 1.0.0.1 – 126.255.255.254 Class B 128.0.0.1 -191.255.255.254 Class C 192.0.1.1-223.255.255.254

12. IP sub netting cont……. Sub net mask We can get subnet mark for a ip number by each network bit value set to 1. It helps to identify whether the network is sub netted or not. Ex: subnet mask for a class C ip is 255.255.255.0 Purposes of sub netting. Eliminate ip wast Fine tune network by utilizing ip in efficient manner.

13. IP sub netting cont……. Ex: You have an ip ranage 192.168.1.0/24. there is two labs to network with 50 and 25 terminals.

14. References. Tanebaum, Andrew S.,2003,Computer networks - 2003 -Pearson Education ; Delhi - xx,891 p. : 4th ed. (modified on 19/04/2010) Meijer,Anton,1982,Computer network architectures -Computer Science Press ; Maryland - xi,396 p. (modified on 19/04/2010)

15. Thank you!!!!!!!!!!!!!