Networking, Data Communication & Computer Networks [1] Data communication is the process of transmitting digital data between two or more points. It allows users to share information and resources over computer networks. [2] A terminal is a device that ends a telecommunication link and is the point where a signal enters or leaves a network. [3] The advantages of computer networks include sharing devices, files, data, information, high-speed internet connections, accessing centralized databases, and better communication using internet services like email.

1. NetworkingData Communication & Computer Networks
S.D.T.Kameera dissanayake

3. What is Data Communications
Is the process of communicating information in binary
form between two or more points.

4. Terminals

5. Definition
– In the context of telecommunications, a terminal is a device which
ends a telecommunications link and is the point at which a signal
enters and/or leaves a network.

6. Communication Networks
– Data Communication networks were developed to
allow users to share information and resources.

7. How is Data Communication
Used?
– Communicating with friends, relatives and associates
– Accessing information on the web. Controlling remote devices such as robots
over IP.
– VOIP
– Facebook,myspace
– Searching for information on Google rather than encyclopedias

8. Computer Networks
– A computer network is a set of interconnected computer & the
peripheral devices.
– For example, it many connected to computer , scanner, printer &
camera.

9. Advantages of Computer
Networks
– Sharing of devices such as printer & scanner.
– Sharing of program / software.
– Sharing of files.
– Sharing of data.
– Sharing of information.
– Sharing of signal high speed internet connection.
– Can access servers centered data base.
– Better communication using internet services such as email, mailing list and internet
Relate chat (IRC).

10. Establishment of
Communication
– Availability of a sender
– Availability of a Receiver
– Availability of a transmission medium
– Availability of response from the receiver.
– Availability of a set of protocols that governs the
communication.

11. Data Communication
– Communication of binary encoded data from one
place to another is known as Data
Communication.

12. A Simple Data Communication
System

13. Internet and Intranet
– The internet generally allows everyone to access all network resources.
– An intranet allows for restricted access to only members of an organization.
– An extranet expands that access by allowing non members such as suppliers
and customers to use company resources.

14. Differences
Internet Intranet Extranet

15. Internet
• This is a network that is accessible to a person
who knows their IP address.
• It is global communication accessed through the
web and literary world wide.

16. Intranet
• This is a network that is not available to the out side of the intranet.
• It is shared content accessed by members within a single organization

17. Extranet
• This is actually an intranet that is partially
accessible to authorized outsiders.
• It is shared content accessed by groups through
cross enterprise boundaries.

18. Network Diagram

19. Intranet-Extranet-Internet

20. Why we use the term internet and
extranets why not as internet?
– Cause this terms has benefits in todays business environment to
communicate more effectively ,both internally with employees
and externally with trading partners and customers
– An intranet enables employees to share information collaborate,
and improve their communications.
– Extranet enables in business to communicate and collaborate
more effectively with selected business partners, suppliers and
customers.

21. Questions

22. 01. What is the terminal?

23. 02. Advantages of Computer Networks?

24. 03. What is the intranet?