fair blind signature based authentication for super peer p2p network authors: xiaoliang wang and...

Fair Blind Signature Based Authentication for Super Peer P2P Network

Authors: Xiaoliang Wang and Xingming SunSource: 2009, Information Technology Journal, vol. 8, issue. 6, pp. 887-894Speaker: Yi-Ru LinDate: 09/17/2010

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National Chung Hsing University

Outline

IntroductionRelated workProposed schemeSecurity analysisComment

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INTRODUCTION

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Two types of DRM mechanismFBST (Fair Blind Signature Trust)

Protect mechanismTrace mechanism

Two types of DRM mechanism

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Identity authenticityTraceabilityPrivacy protectionResilience to a large number of peer

FBST (Fair Blind Signature Trust)

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RELATED WORKS

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Fair blind signatureShamir secret sharing

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Related work – Fair blind signatureSender, Signer, Trusted entity

Sender

TrustedEntity

SignerBlind Signature

Message- signature pair Signature record

Trace

Trace

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Proposed Scheme(1/5)

Shamir’s threshold scheme

PT: prime number PT a≧ 0

t : degree of polynomial a0 : group key

Example:t=3 ; a0=1234 ; n = 6

g(x) = 94x2+166x+1234

(1,1494);(2,1942);(3,2578);(4,3402);(5,4414);(6,5614)

g(x)

= 94x2+166x+1234

g(0) = 1234

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Content DistributionGaussian elimination (高斯消去法 )

In the block, Music provider generates k(k>t) different UID value and distributes them in the p2p network. (UID, h0(UID))

Example H0(UID)’=a+b(UID)’H0(UID)’’=a+b(UID)’ ‘

2x+y-z=8-3x-y+2z=-11-2x+y+2z=-3

2 1 -1 | 8-3 -1 2 | -11-2 1 2 | -3

2 1 -1 | 8 0 1/2 1/2 | 1 0 0 -1 | 1

1 0 0 | 2 0 1 0 | 3 0 0 1 | -1

Assumption UID’=3, UID’’=2, H0(UID)’=10, and H0(UID)’’=5 10=a+3b 5=a+2b a=-5, b=5 => H0(UID)= -5+5(UID)

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Related work – Shamir secret sharing

PROPOSED SCHEME

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InitializationLocal signatureThreshold pair sharingAnonymous and authentication communicationTrace malicious peer

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Initialization

RP

u

SP

Choose: n=pqRSA-like keys:Public: ePrivate: de·d= 1(mod(p-1) ·(q-1))Secure hash function h(·)Publish:(e, n), h(·)

Choose:SRP(·)

Choose:Su(·)

hu(·)

……………

hx(·)………..

ID Hash function

u hu(·)

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Local signature

RP

u

SP

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Threshold pair sharing

RP

u

SP

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Anonymous and authentication communication

RP

u

SP

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Trace malicious peer

RP

u

SP

SECURITY ANALYSIS

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Fundamental security objectivesImpersonateTamperPeer compromiseAnonymityTraceability

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Comments

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Thanks for your listening