Powerpoint for data communication
- 2. WHAT IS A COMPUTER NETWORK? • A Computer network is a number if computers interconnected by one or more transmission paths. • The transmission path often is the telephone line, due to its convenience and universal preserve.
- 3. DATA COMMUNICATION • Data Communication is the exchange of data (in the form of Os and 1s) between two devices via some form of transmission medium (such as a wire cable).
- 4. TYPES OF DATA COMMUNICATION • Data Communication is considered • Local – if the communicating device are in • the same building. • Remote – if the device are farther apart.
- 5. THE DIFFERENCE BETWEEN DATA AND INFORMATION • Data: is a representation of facts, concepts and instructions presented in a formalized manner suitable for communication, interpretation or processing by human beings or by automatic means. • Information: is currently assigned to data by means by the conventions applied to those data.
- 6. FUNDAMENTAL CHARACTERISTICS OF DATA COMMUNICATION • The effectiveness of a data communication system depends on three characteristics. • 1. Delivery: The system must deliver data to the correct destination. • 2. Accuracy: The system must deliver data accurately. • 3. Timeliness: The system must deliver data in a timely manner.
- 8. FIVE COMPONENT OF DATA COMMUNICATION
- 9. THE MESSAGE This is the information (Data) to be communicated; it may be an image, text, number, Audio, or Video.
- 10. THE SENDER The sender is device or person that sends the data. It can be sent using a computer, telephone, or camera.
- 11. THE RECEIVER The receiver is device or person that receives the data. It can be received whether by using a telephone, computer , television.
- 12. Transmission media The physical path by which massage travel from source to destination (sender to receiver) example -twisted pair, coaxial cable, fiber optic, radio waves.
- 13. Protocol A protocol is set of rules that govern data communication. It provide agreement between sender and receiver devices
- 15. SYNTAX Structure or format of the data; for example, fist 8bits are flag, 2nd 8bits are destination address, other 32 bits for massage and last 8bits are for source address
- 16. SEMANTICS this refers to the meaning of each section of bits, how the particular pattern to be interpreted is and what action to be taken. For example 10101010, pattern as a flag (start of data stream)
- 17. TIMING when the data sending ,how fast they can send for example sender is send data at 100 mbps speed, receiver is receive data at 10 mbps what will happen, data will be lost !
- 18. IN DATA COMMUNICATION FOUR BASIC TERMS ARE FREQUENTLY USED • In data communication four basic terms are frequently used. They are: • Data : A collection of facts in raw forms that become information after processing. Signals : Electric or electromagnetic encoding of data. • Signaling : Propagation of signals across a communication medium. • Transmission : Communication of data achieved by the processing of signals.