1. A Double-Efficient Integrity Verification Scheme to Cloud Storage Data Deng Hongyao, Song Xiuli, Tao jingsong 2014 TELKOMNIKA Indonesian Journal of Electrical Engineering Presenter : 陳昱安 Date : 2014/10/6

2. Outline Introduction Schnorr Signature Scheme Safety Integrity Verification Scheme Based on Schnorr Signature Efficient Integrity Verification Scheme Based on Schnorr Signature Security and Performance Analysis Conclusion 2

3. Outline Introduction Schnorr Signature Scheme Safety Integrity Verification Scheme Based on Schnorr Signature Efficient Integrity Verification Scheme Based on Schnorr Signature Security and Performance Analysis Conclusion 3

4. Introduction This paper proposed two integrity verification schemes based on Schnorr Signature Scheme. 4 Safety integrity verification scheme (SIVS). Efficient integrity verification scheme (EIVS).

5. Outline Introduction Schnorr Signature Scheme Safety Integrity Verification Scheme Based on Schnorr Signature Efficient Integrity Verification Scheme Based on Schnorr Signature Security and Performance Analysis Conclusion 5

6. Schnorr Signature Scheme (1/3) 6

7. Schnorr Signature Scheme (2/3) 7

8. Schnorr Signature Scheme (3/3) 8 ?

9. Outline Introduction Schnorr Signature Scheme Safety Integrity Verification Scheme Based on Schnorr Signature Efficient Integrity Verification Scheme Based on Schnorr Signature Security and Performance Analysis Conclusion 9

10. Safety Integrity Verification Scheme Based on Schnorr Signature USER message

11. Safety Integrity Verification Scheme Based on Schnorr Signature USER Challenge Response

12. Safety Integrity Verification Scheme Based on Schnorr Signature USER Request Response

13. Safety Integrity Verification Scheme Based on Schnorr Signature (1/8) 13

14. Safety Integrity Verification Scheme Based on Schnorr Signature (2/8) 14

15. Safety Integrity Verification Scheme Based on Schnorr Signature (3/8) 15

16. Safety Integrity Verification Scheme Based on Schnorr Signature (4/8) 16

17. Safety Integrity Verification Scheme Based on Schnorr Signature (5/8) 17

18. Safety Integrity Verification Scheme Based on Schnorr Signature (6/8) 18 ?

19. Safety Integrity Verification Scheme Based on Schnorr Signature (7/8) 19

20. Safety Integrity Verification Scheme Based on Schnorr Signature (8/8) 20

21. Outline Introduction Schnorr Signature Scheme Safety Integrity Verification Scheme Based on Schnorr Signature Efficient Integrity Verification Scheme Based on Schnorr Signature Security and Performance Analysis Conclusion 21

22. Efficient Integrity Verification Scheme Based on Schnorr Signature (1/3) 22

23. Efficient Integrity Verification Scheme Based on Schnorr Signature (2/3) 23

24. Efficient Integrity Verification Scheme Based on Schnorr Signature (3/3) 24

25. Outline Introduction Schnorr Signature Scheme Safety Integrity Verification Scheme Based on Schnorr Signature Efficient Integrity Verification Scheme Based on Schnorr Signature Security and Performance Analysis Conclusion 25

26. Security and Performance Analysis 26

27. Security Analysis (1/4) 27

28. Security Analysis (2/4) 28

29. Security Analysis (3/4) 29

30. Security Analysis (4/4) 30

31. Performance Analysis 31

32. Outline Introduction Schnorr Signature Scheme Safety Integrity Verification Scheme Based on Schnorr Signature Efficient Integrity Verification Scheme Based on Schnorr Signature Security and Performance Analysis Conclusion 32

33. Conclusion 33 In view of communication costs and computation costs of current integrity verification schemes are too high, this paper proposes two integrity verification schemes SIVS and EIVS based on Schnorr Signature. If the files need to be stored in cloud for a long time, SIVS scheme will be used to verify the integrity of the file. But in short term, EIVS scheme will be used.