A high-level overview of blockchain. Discuss use cases, smart contracts and chaincode, consensus, and types of blockchain.

1. @horeaporutiu
Horea Porutiu
Developer Advocate, Emerging Tech
First Steps with Blockchain

2. Slides
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1. Go to my twitter - @horeaporutiu
2. Link to my slide share is the first pinned tweet

3. Agenda
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1. Blockchain overview
2. Hyperledger overview

4. What is blockchain?
• Blockchain - a continuously growing list of
records, called blocks, which are linked and
secured using cryptography.
• A digital ledger that is replicated across all
network participants
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• Network participants collaborate to maintain the
ledger

5. Imagine
• Walk into your favorite grocery
• You have two options
$5.99/lb $9.99/lb
Farm-raised
🤔 🤔🤔
WildVs.
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6. Problem
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Fisherman Processor Distributor Plate
• There are so many parties involved
• Different parties have different incentives
• Hard to trust that your fish is actually
organic
Traceability of fish from ocean to plate

7. Traceability
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Fisherman Processor Distributor Plate
Insert grocery here
Traceability of fish from ocean to plate

8. Trust
Trust - firm belief in the
reliability, truth, ability, or
strength of someone or
something.
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9. Blockchain and trust
Blockchain helps establish
trust between different
participants in a business
network
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10. Proof of traceability
• What if we
can see on a
map exactly
where the fish
was caught
via a sensor?
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11. Proof of traceability
• What if we can see the fish changing hands from
fisherman, to processor and so on
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12. Proof of traceability
• And then see
the journey it
took to get to
the shelf?
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13. Traceability
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Fisherman Processor Distributor Plate
Traceability of fish from ocean to plate
• Every year, 1 in 10 people
fall ill and 400,000 die
due to contaminated food

14. IBM + Walmart = traceability
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http://www-03.ibm.com/press/us/en/pressrelease/53013.wss

15. Break
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• Any questions up to this point?

16. Shared database?
• A common question is: why can’t I just use a
shared database?
• A shared database does not take care of the trust
aspect and immutability.
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• You can think of blockchain as a database with
some very special characteristics.

17. Identify blockchain use-cases
• If data is used only by one organization, then it’s
most likely not a good use of blockchain
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Distributed Ledger
Distributed
Smart ContractsImmutable
Share data across
multiple companies
Permanent record of
transactions
No central point of
ownership
Business rules visible
to all members

18. Problem
Bank
records
Party A’s
records
Party C’s
records
Auditor
records
Party B’s
records
Party D’s
records
• Today’s business networks: inefficient,
expensive, vulnerable
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19. Solution
Bank
records
Party A’s
records
Party C’s
records
Auditor
records
Party B’s
records
Party D’s
records
Shared, replicated, permissioned ledger
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• Blockchain benefits: consensus, provenance,
immutability, and finality

20. Bitcoin
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21. Types of blockchain
Public Private
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• Open to anyone
• Large computational
requirement
• Participants
incentivized with
cryptocurrency
• Bitcoin
• Need permission to
join the network
• Walmart solution
• Less computational
power required
• Cryptocurrency is
typically not involved
• Transactions can be
kept private

22. Smart Contracts a.k.a chaincode
• Rules agreed
by all parties
within a
network before
the genesis
block
• Provide controlled access to ledger
• Can execute automatically
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23. Sample Smart Contract Code
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24. Blocks
• Set of transactions
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https://www.ybrikman.com/writing/2014/04/24/bitcoin-by-analogy/
• Pointer to previous
block

25. Consensus
• Process to keep all
ledgers on the
network consistent
• Ensures all
participants have
blocks in the same
order
•Implementation
varies
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26. Consensus
• All peers specified by verification policy must have
matching blocks on the ledger for consensus
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https://www.youtube.com/watch?v=2_RgCfjunEU&t=29s

27. IBM + blockchain = BaaS
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• BaaS (Blockchain as a service) based
on Hyperleder Fabric
• Open source software project with over
185 organizations contributing
• IBM Blockchain Starter Plan is free -
used for developing and testing
networks

28. IBM + blockchain = BaaS
@horeaporutiu
• BaaS (Blockchain as a service) based
on Hyperleder Fabric
• Open source software project with over
185 organizations contributing
• IBM Blockchain Starter Plan is free -
used for developing and testing
networks

29. IBM Blockchain Starter Plan Logs
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30. Log Details
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31. Contact
• Questions: horea.porutiu@ibm.com
• Social: Tweets @horeaporutiu
• Site: https://horeaporutiu.github.io/
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32. Questions?
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