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Introduction to Blockchain Technologies
Sarah Azouvi (University College London)
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Privacy International Forum - 19/10/2017
Introduction to Blockchain Technologies Sarah Azouvi (University - - PowerPoint PPT Presentation
Introduction to Blockchain Technologies Sarah Azouvi (University - - PowerPoint PPT Presentation
Introduction to Blockchain Technologies Sarah Azouvi (University College London) Privacy International Forum - 19/10/2017 1 Outline Outline How it works Outline How it works Privacy? Outline How it works Privacy? New applications
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Outline
How it works
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Outline
How it works Privacy?
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Outline
How it works Privacy? New applications
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Bitcoin
- Bitcoin: decentralised cryptocurrency
- No central authority, no banks, no government,
no censorship, no international fees
- Removes the need for a trusted third party
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How does it work?
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How does it work?
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How does it work?
pkB pkA
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How does it work?
tx(pkA pkB) pkB pkA
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How does it work?
tx(pkA pkB) pkB pkA
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How does it work?
tx(pkA pkB) pkB pkA
- Append-only
- Transparent
- Pseudonyms
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How does it work?
tx(pkA pkB) pkB pkA
- Append-only
- Transparent
- Pseudonyms
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How does it work?
tx(pkA pkB) tx(pkA pkA)
?
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How does it work?
Proof of work
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How does it work?
Proof of work
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How does it work?
Proof of work
tx(pkA pkB) tx(pkC pkD) tx(pkE pkF) Previous hash
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How does it work?
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How does it work?
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How does it work?
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How does it work?
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How does it work?
Proof of work
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How does it work?
Proof of work
Longest chain wins
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Why does it work?
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Why does it work?
=
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Why does it work?
=
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What does it guarantee?
- A network of peers that do not trust each other
agree on a set of transactions
- Auditability
- Immutability *
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What it does not guarantee
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What it does not guarantee
- Privacy
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What it does not guarantee
- Privacy
- Solve every problem
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Privacy
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Privacy
- Transparent
- Transactions are linked
- Traceable!
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Privacy
- Transparent
- Transactions are linked
- Traceable!
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Privacy
pkA pkB pkB pkC pkD pkD pkE pkF
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Privacy
- Solution: mixing service
pkA pkB pkC pkD pkE pkF
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Privacy
- Solution: mixing service
pkA pkB pkC pkD pkE pkF
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Privacy
- Solution: mixing service
pkA pkB pkC pkD pkE pkF
- New currency: Zcash (ZKP), Monero (ring
signatures)
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Extensions
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Extensions
- Ethereum
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Extensions
- Ethereum
- Identity management system
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Extensions
- Ethereum
- Identity management system
- Permissioned blockchains, no currencies
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Extensions
- Ethereum
- Identity management system
- Permissioned blockchains, no currencies
- Privacy preserving blockchains
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Extensions
- Ethereum
- Identity management system
- Permissioned blockchains, no currencies
- Privacy preserving blockchains
- Many others decentralised applications!
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Ethereum
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Ethereum
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Ethereum
Smart Contract
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Ethereum
Smart Contract tx(pkB smart contract )
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Ethereum
- ICO: Decentralised Kick-starter
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Ethereum
- ICO: Decentralised Kick-starter
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Identity Management
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Identity Management
- Control over your data
- Standardise identity management
- Less complex
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Identity Management
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Identity Management
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Identity Management
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Identity Management
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Industry application
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Industry application
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Industry application
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Industry application
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Research
- Privacy
- Sustainability
- Scalability
- New applications: decentralized versions of identity
management, DNS and public-key infrastructures, notary publics, and file storage
- Usability
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