1. Data communication 1 C31102 IT 2 Computer Center Pluakdaengpittayakom

2. Data Communication Role Make efficiency on resource using Many processer can processing parallel

3. Network range Processor distance areanamed 0.1 mSame circuitDataflow 1 m1 mSame systemMulti processor 10 mSame roomMulti processor 100 mSame buildingLocal Area 1 kmSame organizeLocal Area 10 kmSame cityLocal Area 100 kmSame countryWide area 1000 kmInternationalWide area 10000 kmInter planetSuper Wide area

4. Advantage of Data Communication Fast Communicate Valid of data Work speed Economic

5. Fast Communication Easy to save data Not write it again

6. Valid of Data Check system between transmit

7. Parity bit or Check bit 2 format Even Parity number of 1 bit must have even number Odd Parity number of 1 bit must have add number 1 1 1 0 0 0 1 0 1 1 0 1 0 1 0 1 1 0 0 0 1 1 1 1 0 1 0 1

8. Work speed In general electron can move same speed as light You can find data from other side of the world

9. Economic Can share data on low cost

10. OSI standard OSI : Open System Interconnection 7 layers

11. OSI standard

12. 7 OSI layers application layer presentation layer session layer transport layer network layer data link layer physical layer

13. Application layer Connect user directly

14. presentation layer Format data for present

15. Session layer Initiate communication Simplex, half duplex or full duplex

16. Transport layer Define port to transmit

17. Network layer Define route

18. data link layer Divide data to package

19. physical layer Media to transmit

20. summation