Making Bitcoin Exchanges Transparent - TIK€¦ · James Guthrie | 24/09/15 | 16 Trust in Bitcoin...
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| | James Guthrie James Guthrie Christian Decker, Jochen Seidel, Roger Wattenhofer 24/09/15 1 Making Bitcoin Exchanges Transparent
Transcript of Making Bitcoin Exchanges Transparent - TIK€¦ · James Guthrie | 24/09/15 | 16 Trust in Bitcoin...
||James Guthrie
James Guthrie Christian Decker, Jochen Seidel, Roger Wattenhofer
24/09/15 1
Making Bitcoin Exchanges Transparent
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Introduction
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Introduction
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Introduction
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IntroductionPeer to Peer
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IntroductionPeer to Peer
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header
James Guthrie 7
Introduction
headerheader
Peer to Peer
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Introduction
header headerheader
Peer to Peer
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IntroductionPeer to Peer
Transaction History
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IntroductionPeer to Peer
Transaction History
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IntroductionPeer to Peer
Transaction History
Growth
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Sellers
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Bitcoin Exchanges
Exchange
Buyers
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Trust in Bitcoin Exchanges
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Trust in Bitcoin Exchanges
18 of 40 exchanges folded
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Trust in Bitcoin Exchanges
18 of 40 exchanges folded
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Trust in Bitcoin Exchanges
18 of 40 exchanges folded
650k bitcoins lost/stolen
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Trust in Bitcoin Exchanges
18 of 40 exchanges folded
650k bitcoins lost/stolen
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Trust in Bitcoin Exchanges
18 of 40 exchanges folded
650k bitcoins lost/stolen
No higher power
No help from law enforcement
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650k bitcoins lost/stolen
18 of 40 exchanges folded
No higher power
James Guthrie 19
Trust in Bitcoin Exchanges
No help from law enforcement
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Legitimacy of Bitcoin Exchanges
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Legitimacy of Bitcoin Exchanges
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Legitimacy of Bitcoin Exchanges
Third-party audit
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Legitimacy of Bitcoin Exchanges
Third-party audit
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Legitimacy of Bitcoin Exchanges
Third-party audit
Renowned third-party audit (PwC)
Trust in third party Cost Frequency Privacy
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Automated Software-Based Audit
Assets Liabilities
≥Solvency
Privacy
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Trusted Computing
Executable
Trusted Execution
Result + Proof of ExecutionOutput
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Overview of Audit Process
Value of Assets Value of Liabilities
≥
Blockchain Keys + Signatures Customer IDs + Balances
SolvencyBlockchain hash Customer data hash
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Customer Verification
Bob : 20Alice : 10 Cath : 15 David : 90
h(Bob : 20)h(Alice : 10) h(Cath : 15) h(David : 90)
h(A||B) h(C||D)
h(AB||CD)
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Customer Verification
Bob : 20Alice : 10 Cath : 15 David : 90
h(Bob : 20)h(Alice : 10) h(Cath : 15) h(David : 90)
h(A||B) h(C||D)
h(AB||CD)
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Customer Verification
Bob : 20Alice : 10 Cath : 15 David : 90
h(Bob : 20)h(Alice : 10) h(Cath : 15) h(David : 90)
h(A||B) h(C||D)
h(AB||CD)
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Customer Verification
Bob : 20Alice : 10 Cath : 15 David : 90
h(Bob : 20)h(Alice : 10) h(Cath : 15) h(David : 90)
h(A||B) h(C||D)
h(AB||CD)
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Limitations of Trusted Execution Platform
4 KB Stack
128 KB Heap
116 KB Input
512 KB Program
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Limitations of Trusted Execution Platform
4 KB Stack
128 KB Heap
116 KB Input
512 KB Program
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Limitations of Trusted Execution Platform
4 KB Stack
128 KB Heap116 KB Input
512 KB Program
Input space
Blockchain
Size
0GB 7.5GB 15GB 22.5GB 30GB
Input space
Address Balances
Size
0MB 40MB 80MB 120MB 160MB
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Limitations of Trusted Execution Platform
4 KB Stack
128 KB Heap116 KB Input
512 KB Program
Memory constraints
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Limitations of Trusted Execution Platform
4 KB Stack
128 KB Heap116 KB Input
512 KB Program
Memory constraints
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Limitations of Trusted Execution Platform
4 KB Stack
128 KB Heap116 KB Input
512 KB Program
Memory constraints
Time constraints • 200ms-1s overhead • 0.5-1s cooldown
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Overview of Audit Process
Value of Assets Value of Liabilities
≥
Blockchain Keys + Signatures Customer IDs + Balances
SolvencyBlockchain hash Customer data hash
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Overview of Audit Process
Value of Assets Value of Liabilities
≥
Keys + Signatures Customer IDs + Balances
SolvencyAddress Balance hash Customer data hash
Address Balances
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Iterative Customer Verification
Bob : 20Alice : 10 Cath : 15 David : 90
h(Bob : 20)h(Alice : 10) h(Cath : 15) h(David : 90)
h(A||B) h(C||D)
h(AB||CD)
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Iterative Merkle Tree
C
C
Õ
B
B
Õ
R
2
nentries 2
nentries
1 to 2
n+1entries
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Summary
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Summary
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Summary
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Summary
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Summary
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Summary
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Summary
Assets Liabilities
≥
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Summary
A Li≥
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Summary
A Li≥Value of Assets Value of Liabilities
≥
Blockchain Keys + Signatures Customer IDs + Balances
SolvencyBlockchain hash Customer data hash
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Summary
A Li≥ Valu Valu
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Summary
A Li≥ Valu Valu
Bob : 20Alice : 10 Cath : 15 David : 90
h(Bob : 20)h(Alice : 10) h(Cath : 15) h(David : 90)
h(A||B) h(C||D)
h(AB||CD)
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Summary
A Li≥ Valu Valu
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Summary
A Li≥ Valu Valu
Value of Assets Value of Liabilities
≥
Keys + Signatures Customer IDs + Balances
SolvencyAddress Balance hash Customer data hash
Address Balances
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Summary
A Li≥ Valu Valu
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Summary
A Li≥ Valu ValuC
C
Õ
B
B
Õ
R
2
nentries 2
nentries
1 to 2
n+1entries
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Summary
A Li≥ Valu Valu
C
C
Õ
B
B
Õ
R
2
nentries 2
nentries
1 to 2
n+1entries
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Thank you
Questions?
