AdHocPairing Spontaneous audio based secure device pairing for - - PowerPoint PPT Presentation

Information Systems Architecture Science Research Division

AdHocPairing

Spontaneous audio based secure device pairing for Android mobile devices

Stephan Sigg, Ngu Nguyen, An Huynh and Yusheng Ji

iwssi 2012, 18.06.2012, Newcastle

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

possible messages X possible codewords C

x c′

Decoding Encoding

c

C

Generation of Audio fingerprints1 Utilise Fuzzy cryptography to obtain identical keys at devices2

• 1J. Haitsma and T. Kalker, A highly robust audio fingerprinting system, ISMIR 2002
• 2P. Tuyls, B. Skoric, T. Kevenaar, Security with noisy Data, Springer, 2007

Stephan Sigg | AdHocPairing | 2

Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

AdHocPairing: Android-App for secure ad-hoc device pairing

Stephan Sigg | AdHocPairing | 3

Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

AdHocPairing: Android-App for secure ad-hoc device pairing

Stephan Sigg | AdHocPairing | 4

Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

Case study with up to four Android devices 3 · Nexus S, 1 · Nexus One Dominant audio created by audio source Distance to audio source kept identical (15cm to 4m)

Stephan Sigg | AdHocPairing | 5

Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

50 100 150 200 250 300 350 400 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1

Distance between devices [cm] Fraction of identical bits in fingerprints (median)

Distance of fingerprints at remote devices

With distance, similarity in fingerprints decreases Security sphere of about 2 meters Confirms earlier experiments in other settings

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Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Conclusion

Implementation on android Case study with mobile phones Synchronisation of context without data transmission

Stephan Sigg | AdHocPairing | 7

Information Systems Architecture Science Research Division

Questions?

Stephan Sigg sigg@nii.ac.jp

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Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

Hardware-originated synchronisation offset

Stephan Sigg | AdHocPairing | 9

Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

Hardware-originated synchronisation offset

s 1

i,j

M

k,j−1

M

k,j

M pi−1

. . .

p1

. . .

s j−1

. . . . . .

s j s M M Mi−1,j

i,j−1

i−1,j−1

pi p n k

Audio sequence Audio Pattern

. . . . . . . . . . . . . . . . . . . . . . . .

Minimum cost in row k

Approximate pattern matching with arbitrary sequence3

• 3T. F. Smith and M. S. Waterman. Identification of common molecular subsequences. Journal of molecular biology,

147(1):195ˆ a197, Mar. 1981 Stephan Sigg | AdHocPairing | 10

Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

Hardware-originated synchronisation offset4 Synchronisation in the order of 3ms possible No additional data transmitted among devices

4Ngu Nguyen, Stephan Sigg, An Huynh, Yusheng Ji, Using ambient audio in secure mobile phone communication, PerCom 2011 Stephan Sigg | AdHocPairing | 11

Information Systems Architecture Science Research Division

Motivation and Problem statement Case study Conclusion

Security from environmental stimuli

Hardware-originated synchronisation offset

Stephan Sigg | AdHocPairing | 12

Information Systems Architecture Science Research Division