The document discusses various topics related to blockchain including definitions of blockchain and how it differs from traditional databases. It also discusses key challenges related to identity, privacy and trust on blockchain networks. Specific topics covered include pseudonymity, permissioned blockchains, homomorphic encryption, smart contracts, distributed autonomous organizations, and potential future applications of blockchain such as international payments, voting systems, and medical records storage.

1. BLOCKCHAIN – FINTECH & BEYOND

2. Blockchain – Definition
● Pseudonmity- The ability that
users are not easily identified
Source : Consensus : Immutable Agreement for Internet of Value - KPMG

3. Blockchain – Definition (contd)

4. Blockchain or Database (question of ACID vs BASE)
“You can have at most two of these properties for any shared-data system… the
choice of which feature to discard determines the
nature of your system.” – Eric Brewer

5. Blockchain – unique question of Consensus
Source : Consensus : Immutable Agreement for Internet of Value - KPMG

6. Blockchain – ecosystem (a recent snapshot)
Source : Consensus : Immutable Agreement for Internet of Value - KPMG

7. Blockchain – usecases
Source : Consensus : Immutable Agreement for Internet of Value - KPMG

8. Blockchain – key challenges
● Identity- General approach has been to
support pseudonyms
● Privacy – Blockchain as a paradigm
expects all data to be available
● Trust – Question of trust in a
decentralised system

9. Privacy
● Permissioned Blockchain – having Blockchain
which has permission
● Homomorphic encryption – Allowing
operations with out revealing content

10. Homomorphic Encryption
● Homomorphic Encryption – the challenge of
processing without knowing what is being
asked
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11. Homomorphic Encryption
● Homomorphic Encryption – Oct 2008 Craig
Gentry came up with solution
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12. Blockchain and graph analysis

13. Identity
● Identity- General approach has been to
support pseudonyms
● Identity verification – strength of
verification of identity is as good as on
boarding

14. Smart Contracts
● “The basic idea behind smart contracts is that many kinds of
contractual clauses (such as collateral, bonding, delineation of
property rights, etc.) can be embedded in the hardware and
software we deal with, in such a way as to make breach of
contract expensive (if desired, sometimes prohibitively so) for
the breacher.”
● “Smart contracts combine protocols, user interfaces, and
promises expressed via those interfaces, to formalize and secure
relationships over public networks. This gives us new ways to
formalize the digital relationships which are far more functional
than their inanimate paper-based ancestors”
● “Smart contracts reduce mental and computational transaction
costs.”
– “Formalizing and Securing Relationships on Public Networks,” Nick Szabo

15. DISTRIBUTED AUTONOMOUS
ORGANISATIONS (DAOs)

17. Smart Contracts – security challenges (moritorium)

18. Smart Contracts – security challenges (contd)

19. Smart Contracts – future evil side (contd)

20. Smart Contracts – future (evil side)
● Allows validation of conditions and
implement actions, whether legal or illegal
● Ransom smart contract – a smart contract
that would trigger an action if a ransom is
not paid

21. GIBSON
21
“THE FUTURE IS ALREADY HERE,
IT”S JUST NOT EVENLY DISTRIBUTED (YET)”
– William Gibson

22. Anish Mohammed
@anishmohammed
QUESTIONS

23. Blockchain – the real uses
International payments
Contracts
Transaction logs
Voting systems
Micro-transactions
Registries
Multi-signatory contracts
DACs
DAP
DAO
2
3
Distributed Censorship resistance
Distributed Identity verification
Decentralised Governance Services
Blockchain Dispute resolution
Futarchy
Genetic information storage
File storage
EMR
Crowdsourcing
Smart property

24. Bitcoin – Byzantine Agreements
● Anonymous Byzantine Agreements are
vulnerable to Sybil attacks
● Moderately-Hard Puzzles(a.k.a Proof-of-
Work) as anonymous identity tools were
proposed since mid 90s
● Finally, an approach was used(along with
pretty informal definition) by “Satoshi
Nakamoto”

25. Bitcoin/Blockchain – Proof of Stake
● Anonymous Byzantine Agreement with
internal tokens as identity tools
● No mining. Right to generate a block
depends on stake
● So a bunch of oracles (hit < target)
● Cumulative difficulty is the chain quality
measure(in a blocktree)
● E.g. Tendermint,Hyperledger,SCP

26. Bitcoin – Timeline
● Anonymous Byzantine Agreement with
internal tokens as identity tools
● No mining. Right to generate a block
depends on stake
● So a bunch of oracles (hit < target)
● Cumulative difficulty is the chain quality
measure(in a blocktree)
● E.g. Tendermint,Hyperledger,SCP

27. Bitcoin/Blockchain – Reading List
● Anonymous Byzantine Consensus from
Moderately-Hard Puzzles: A Model for Bitcoin
(A. Miller / J. LaViola)
● Research Perspectives and Challenges for
Bitcoinand Cryptocurrencies (J. Bonneau, A.
Miller et al)
● The Bitcoin Backbone Protocol: Analysis and
Applications
(https://eprint.iacr.org/2014/765.pdf )