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FinTech Lecture 12 : DeFi : Decentralized Finance

Kenji Saito
December 17, 2021

FinTech Lecture 12 : DeFi : Decentralized Finance

Slides I used for Lecture 12 of FinTech - Financial Innovation and the Internet 2021 Fall at Graduate School of Business and Finance, Waseda University on December 17, 2021.

Kenji Saito

December 17, 2021
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  1. Changes in the economy and labor.
    FinTech — Financial Innovation and the Internet 2021 Fall
    Lecture 12 : DeFi : Decentralized Finance
    Kenji Saito, Graduate School of Business and Finance, Waseda University
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.1/39

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  2. This class is recorded
    Camera ON is recommended, but not required
    Zoom names : change your names to whatever you want to be called
    Please link your Zoon names to your real names in your reports
    Zoom names are important, because if you choose to be called by your real names, still I don’t know whether I
    should call you by your given or family names
    You do need to speak often (we are going to have a lot of dialogues)
    We will use breakout rooms a lot, but those won’t be recorded unless you do it yourselves (need to be allowed)
    Keep your Zoom client updated!
    We might use latest features
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.2/39

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  3. The lecture slides can be found at :
    https://speakerdeck.com/ks91
    Recording and chat text will be posted at Moodle and Discord
    Trial automatic transcription will be posted at Discord
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.3/39

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  4. Schedule (provisional)
    Lecture 1 9/24 Overview of FinTech (1) •
    Lecture 2 10/1 Overview of FinTech (2) •
    Lecture 3 10/8 Internet Technology and Governance (1) •
    Lecture 4 10/15 Internet Technology and Governance (2) •
    Lecture 5 10/22 Internet Governance and the World of Apps •
    Lecture 6 10/29 The World of Apps - continued •
    Lecture 7 11/12 Basics of Cryptography and Blockchain •
    Lecture 8 11/19 Blockchain •
    Lecture 9 11/26 Blockchain and Smart Contracts •
    Lecture 10 12/3 Smart Contracts •
    Lecture 11 12/10 Further Smart Contracts •
    Lecture 12 12/17 DeFi : Decentralized Finance •
    Lecture 13 1/7 Cyber-Physical Society and Future of Finance
    Lecture 14 1/14 FinTech Ideathon
    Lecture 15 1/21 Presentations and Conclusions
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.4/39

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  5. Last Week, We Did. . .
    Overview of Ethereum
    With demo
    Smart Contract Programming
    Understanding Applications of Blockchain
    Assignment
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.5/39

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  6. Today’s Topics
    Smart Contract Programming Demo
    Let’s sell and buy land rights with digital tokens
    Understanding Applications of Blockchain (revisited)
    Assignment Review — The DAO Attacked
    Discussion on the DAO Attack
    Blockchain and Anonymity — How to Disappear
    Assignment
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.6/39

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  7. Demonstration : Automated Escrow
    An attempt to automate real-estate brokerage, banking, and Legal Affairs Bureau
    (or judicial scrivener)
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.7/39

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  8. ex. Automated Escrow to Purchase Land (automation of centers)
    %FpOFEb"JS`
    SFUVSOMBOE
    1VSDIBTF$POUSBDU
    -BOE"TTFU
    MBOE
    EFQPTJU
    USBOTGFSMBOESJHIUTUPCVZFS USBOTGFSQBZNFOUUPTFMMFS
    QBZNFOU
    EFQPTJU
    %JHJUBM5PLFO
    DSFBUFBOEpYJOUIFBJS
    FJUIFSDBOEPUIJT
    DSFBUFBOEpYJOUIFBJS
    DBOGSFFMZKPJOBOEMFBWF
    DBOGSFFMZKPJOBOEMFBWF
    4FMMFS
    #VZFS
    JOUFSOBM
    TUBUF
    SFUVSONPOFZ
    TFUUMF
    USBOTGFS
    JOUFSOBM
    TUBUF
    USBOTGFS
    JOUFSOBM
    TUBUF




    1. Purchase contract is fixed in the air to prevent taking away of land or money (both parties can verify the contract)
    2. Deposit land rights and purchase money in the contract (if they change their minds, they can take them back)
    3. When settled (anyone can do it if both right and money are deposited), the rights and money for the property are
    transferred simultaneously
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.8/39

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  9. Value of Automated Escrow
    From “My Father’s 100 Million Yen Debt Repayment Story” by Human Mao
    http://ningenmao.blog.jp/archives/6163807.html
    On the very day of repayment, they rented a place at a hotel and all the people involved
    gathered there
    There were more than 20 people in total, including real estate companies, bankers, and
    judicial scriveners
    Since the land was mortgaged by the bank, the mortgage had to be removed as soon as the
    money was repaid, and in order to make sure that this was done correctly, they got together
    and proceeded solemnly
    ↑ An example of non-automated version of the process
    Great human drama if you can read Japanese by the way
    Mao finds a photo of her father who went to India just three days after she was born, and learns that he had a debt
    of 100 million yen in the past, and that it was related to his trip to India
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.9/39

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  10. Sample Code and Demo
    git clone from GitHub
    $ git clone https://github.com/ks91/sample-smart-contracts.git
    Follow README
    1. Setup a sample token project with brownie
    Brownie is a Python-based Ethereum programming and test environment
    Javascript-based one is called Truffle, and an Ethereum remote procedure call client is called Ganache
    See? Engineers are fun people to work with!
    2. Copy the content of contracts, scripts and tests directories of this sample project into the
    corresponding directories of the token project
    3. Compile
    4. Test
    Today, I will demonstrate manually the test for automated escrow
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.10/39

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  11. settle() from OneTimeEscrow
    function settle() public returns (bool) {
    require(_token_.balanceOf(address(this)) >= _price_); /* ’this’ means this contract */
    require(_asset_.getOwner() == address(this));
    _token_.transfer(_seller_ , _price_);
    _asset_.transfer(_buyer_);
    emit Settled(); /* event log */
    return true;
    }
    Just to introduce the settle() part from the sample code
    Only if both the price and the asset are deposited with the contract,
    It transfers money to the seller and asset to the buyer
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.11/39

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  12. Open console and connect to Ropsten testnet
    Use brownie console
    >>> network.disconnect() # disconnect from the default, simulated environment of Ethereum
    >>> network.connect(’ropsten’)
    >>> len(accounts)
    0
    >>> accounts.add(paste the hexadecimal string of the private key here)

    >>> accounts[0].balace()
    Here is the ETH balance of the account
    We set up two accounts
    Once you have created multiple accounts, you can try to transfer ETH, for example as follows
    >>> accounts[0].transfer(accounts[1], "1 ether")
    But before that, you may want to feed the accounts with Ropsten ETH from some public faucet
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.12/39

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  13. Test Code (1)
    from brownie import *
    import pytest
    def test_deploy_and_settle(Token, IndivisibleAsset, OneTimeEscrow):
    asset = accounts[0].deploy(IndivisibleAsset, "5322 Endo", "mˆ2", 300)
    token = accounts[0].deploy(Token, "Test Token", "TEST", 18, "1000 ether")
    Deploying token and asset contracts
    The above is just the test code as it is, so in the console we will just type the inside of the function
    First, let’s do seller = accounts[0] and buyer = accounts[1] for readability
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.13/39

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  14. Test Code (2)
    token.transfer(accounts[1], 300, {’from’: accounts[0]})
    escrow = accounts[0].deploy(OneTimeEscrow, token, accounts[1], asset, accounts[0], 300)
    Sending 300 coins from seller (accounts[0]) to buyer (accounts[1]) to prepare
    Because the buyer has to cast a transaction that pays 300 coins
    Deploying Escrow Contracts
    Buyer is accounts[1], seller is accounts[0], and the price is 300 coins
    Since we are using the sample arguments of the baked Token as they are, 300 coins is actually a
    very small unit, like wei in ETH
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.14/39

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  15. Test Code (3)
    token.transfer(escrow, 300, {’from’: accounts[1]})
    asset.transfer(escrow, {’from’: accounts[0]})
    assert token.balanceOf(accounts[0]) == 999999999999999999700
    assert token.balanceOf(accounts[1]) == 0
    assert token.balanceOf(escrow) == 300
    assert asset.getOwner() == escrow
    Buyer (accounts[1]) deposits 300 coins in escrow, and
    Seller (accounts[0]) deposits the asset in escrow
    assert tests a statement, and fails the test if it turns out to be false
    But we are in console (not doing an automated test), so we just see the values
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.15/39

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  16. Test Code (4)
    escrow.settle({’from’: accounts[0]})
    assert token.balanceOf(accounts[0]) == 1000000000000000000000
    assert token.balanceOf(accounts[1]) == 0
    assert token.balanceOf(escrow) == 0
    assert asset.getOwner() == accounts[1]
    Calling settle() and closing the transaction
    In this code, it is called by seller (accounts[0]), but it is OK to call from either side
    Let’s see some transactions on an Ethereum Ropsten testnet explorer
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.16/39

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  17. Understanding Applications of Blockchain
    In one single diagram
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.17/39

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  18. Understanding Applications of Blockchain
    Token
    Smart Contract Provenance
    Fungible
    Non-redeemable
    Fungible
    Redeemable
    Non-fungible
    Redeemable
    Non-fungible
    Non-redeemable
    Certifying
    Identifying
    payment
    ID card
    security token
    last will
    logistics
    insurance claim
    Tracking
    Sensing
    fiat money
    crypto-pet
    Proves you are the one
    since you can handle
    the private key?
    Transfers numerical
    representations of
    debt / asset?
    Maintains authenticity
    of registered code, data
    and resulted states?
    (Authority) issues
    certificates about
    some content?
    Updates records about
    sustained presences?
    Is data still valid even
    if the subject is gone?
    Many think we implement token and provenance apps with smart contracts, but. . .
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.18/39

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  19. Assignment Review
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.19/39

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  20. Assignment 5. “The DAO Attacked”
    In 2016, an autonomous decentralized investment fund “The DAO” leaked
    3.5M ETH in an attack that exploited a bug in a smart contract, but this
    incident was made to look like it never happened, by the hard fork of Ethereum
    (1) Choose between A) public policy position (of a country with many victims), or
    B) management position at The DAO
    (2) Discuss briefly what would have been the best thing to do from your position
    Deadline and how to submit
    December 14, 2021 at 17:59 JST
    From Moodle (mandatory) — this time, we are using a Q&A forum
    So that your classmates can read your report, refer to it, and comment on it
    Optionally, you can also post to #assignments channel at Discord
    So that anyone in our Discord can read your report, refer to it, and comment on it
    Just plain text, and be concise, please
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.20/39

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  21. Trends and Measures
    Trends . . . of your reports Measures . . . how to improve the class
    21 out of 29+α students submitted (always better late than never)
    Your choices of positions :
    public policy position : 12; business management position : 9
    Your opinions on the hard fork :
    positive : 9; negative : 4; neither : 8
    I think your opinions were well thought out from each standpoint
    Many of you could have written your answers a little shorter
    Try to use bullet points or other ways to make it easier for the reader to
    read and get your point across
    I will let you discuss with your thoughts
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.21/39

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  22. Discussion
    cf. “The History of the DAO and Lessons Learned”
    https://blog.slock.it/the-history-of-the-dao-and-lessons-learned-d06740f8cfa5
    This is still a one-sided view, but it is useful to know the details of the incident and response
    We will breakout and use miro mind map
    Connect your thoughts to the node of your breakout room
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.22/39

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  23. How to Disappear
    Blockchain and Anonymity
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.23/39

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  24. ZoE (Zcash on Ethereum)
    In Ethereum, too, an “address” is a public key digest
    In Ethereum, which manages account status (balance, etc.) rather than UTXO
    (coin with destination), it’s difficult to adopt the Bitcoin-like method of changing
    the receiver’s address from transaction to transaction
    Which is not a perfect way to hide themselves anyway
    zk-SNARKs, zero-knowledge proof algorithm used in Zcash, has also been
    implemented for Ethereum
    Can conceal transactions
    (Who sent it to whom ← not straightforward, and) how much?
    Deployed with Byzantium hard fork in 2017
    Gas (transaction cost) is expensive
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.24/39

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  25. zk-SNARKs
    Zero Knowledge - Succinct (compact) Non-interactive ARgument of Knowledge
    3 parts
    G is Generator : G(λ, C) → (pk, vk) where C is a circuit, λ is a secret
    Circuit (or function) C returns true or false; pk is the prover key, vk is the verifier key
    P is Prover : P(pk, x, w) → π
    where x is the public input of C, w (witness) is the secret input of C
    π is the proof
    V is Verifier : V (vk, x, π) = true ⇒ ∃w : C(x, w) = true
    Can perform in Ethereum by executing V inside smart contracts
    G and P (knows secret) are executed “off-chain” so to speak
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.25/39

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  26. C’s (circuits)
    to Conceal Balances and Remittances
    Use the cryptographic hash function H
    The contract manages H(a’s balance) for all accounts a
    C
    s
    (x, w) for sender :
    x is [H(pre-tx balance), H(post-tx balance), H(remittance)], w is [pre-tx balance, remittance]
    Confirm pre-tx balance ≥ remittance
    Apply H to w to verify that H(pre-tx balance) and H(remittance) in x are correct
    Verifies that H(post-tx balance) in x equals H(pre-tx balance − remittance)
    C
    r
    (x, w) for receiver :
    x is [H(pre-tx balance), H(post-tx balance), H(remittance)], w is [pre-tx balance, remittance]
    Apply H to w to verify that H(pre-tx balance) and H(remittance) in x are correct
    Verifies that H(post-tx balance) in x equals H(pre-tx balance + remittance)
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.26/39

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  27. Contract to Conceal Balances and Remittances
    Accepts the following as arguments
    (sender address is self-evident as the caller of the contract)
    Receiver address, H(remittance), H(post-tx balance
    s
    ), H(post-tx balance
    r
    )
    π
    s
    , π
    r
    obtained by applying P in advance
    Verifies sending by V (vk
    s
    , [H(balances
    ), H(post-tx balances
    ), H(remittance)], π
    s
    )
    Verifies receiving by V (vk
    r
    , [H(balancer
    ), H(post-tx balancer
    ), H(remittance)], π
    r
    )
    Replaces both H(balance) with their H(post-tx balance)
    Sender and receiver need to communicate off-chain
    They cannot tell how much each other had and has now
    Others cannot tell, in addition to the above, how much was sent
    But they can tell who sent money to whom
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.27/39

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  28. In One Picture
    Fact that Alice sent
    some money to Bob is
    known
    To avoid preimage at-
    tacks, balances and re-
    mittances should contain
    many digits below deci-
    mal point
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.28/39

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  29. How to Disappear Completely
    Let’s think of a method of remittance using zk-SNARKs that conceals the
    following
    Who sends money? ← NEW!
    To whom? ← NEW!
    How much?
    How much were the balances of those before remittance, and how much
    afterward?
    Is our solution perfect? What problems are there?
    ↑ This was an assignment for the class for the past couple of years
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.29/39

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  30. Kenji’s Solution (second receiver as sender agent) (may be a known solution)
    H′ can be any arbitrary
    function, but linkability
    remains a problem
    Balance’s digits below
    decimal point is like a
    private key, protected by
    H
    Carole can run verifiers
    prior to issuing a trans-
    action to verify if she can
    really receive the fee
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.30/39

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  31. Tor (The Onion Router)
    What is Onion Routing? → technology for anonymity
    Build a circuit that runs through multiple nodes from the user to the
    terminating node
    The user shares a shared key with each node that appears on the
    circuit
    (the user does not tell who they are)
    Data encryption is applied for the terminating node, and then for
    each node appearing in the circuit in reverse order, and finally the
    data is sent
    The relay peels off the encryption at each hop, as if it were an
    onion, and sends it to the next node
    The relay has no way of knowing what content is being sent from
    whom to whom
    Reference
    Tor : https://www.torproject.org
    There are concerns about its application to crimes, but it is also a tool for protecting citizens’
    privacy and enforcing human rights
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.31/39

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  32. More on Anonymity
    This may be a disturbing story, but. . .
    How do we share and transfer a request to Golgo 13 (assassin) while hiding
    his and the client’s identities. . .
    From each other and third parties?
    Of course, we want to keep secret the contents of the request and the
    amount of money in question
    What impact would this have on law enforcement?
    Is it good for society that this is possible?
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.32/39

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  33. Bitcoin and Anonymity — Pseudonymity
    “Address” is the digest of a public key
    Must equal the digest derived from the public key
    presented by the certifier, and
    Digital signature by the certifier must be verified with
    the public key
    ⇒ Has corresponding private key ⇒ authorized user
    Existence of an entity can be inferred if the
    same “address” is used more than once
    However, it is not known which specific
    individual the subject is (no linkability)
    Once it is linked somewhere, anonymity is
    stripped
    Ex : tied to a bank account at an exchange
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.33/39

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  34. Bitcoin and Anonymity — Linkability
    Just one-time use of the same “address” is
    encouraged
    They try to minimize the extent to which they are
    identified when an address is linked to some
    identity. . .
    Since “address” is actually referred to as TX
    input, a series of addresses can be clustered
    to estimate the existence of a subject by
    analyzing the appearance distribution
    Ex : D.Ron and A.Shamir, “Quantitative Analysis of
    the Full Bitcoin Transaction Graph”
    https://eprint.iacr.org/2012/584.pdf
    Ex : S.Meiklejohn et al., “A Fistful of Bitcoins:
    Characterizing Payments Among Men with No
    Names”
    http://conferences.sigcomm.org/imc/2013/papers/
    imc182-meiklejohnA.pdf
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.34/39

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  35. Mixing (Concealing Recipients)
    "
    #
    4IBSFE8BMMFU
    BEESFTT
    BEESFTT
    BEESFTT
    BEESFTT
    #5$
    #5$
    #5$
    #5$
    "DDPSEJOHUPUIFVTFST`JOTUSVDUJPOT
    UIFNPOFZJTUSBOTGFSSFEGSPN"UP#
    $UP% BOEDPNNJTTJPOJTDIBSHFE
    CVUUIFSFMBUJPOTIJQTCFUXFFO"BOE#
    $BOE%BSFVOLOPXOGSPNUIFUYIJTUPSZ
    %
    $
    Mixing operators know the secret . . . is there any possibility of undercover investigations in which law enforcement is in
    fact in charge of mixing?
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.35/39

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  36. TumbleBit
    Eliminates trust in mixing in Bitcoin
    Assumes “tumbler” for mixing (but you can’t trust them)
    Protocol to send 1 BTC from Alice to Bob
    (1) Tumbler makes time-limited deposit of 1 BTC on blockchain (upon Bob’s request)
    Bob’s signature and the solution of a puzzle will release this 1 BTC
    (2) Bob blindfolds (like multiplies by a random number) the puzzle (that tumbler can still solve, but they don’t
    know for whom it was made), and sends it to Alice
    (3) Alice blindfolds the sent puzzle once again (tumbler can still solve it)
    (4) Alice makes a time-limited deposit of 1 BTC on blockchain
    This 1 BTC can be obtained with tumbler’s signature and the solution to the double-blindfolded puzzle
    (5) Tumbler gets the 1 BTC with signature and solution to the double-blindfolded puzzle
    This solution is a double-blindfolded version for the original puzzle, and cannot unlock the payment to Bob
    (6) Alice takes away one blindfold from the solution, and sends it to Bob
    (7) Bob takes away one more blindfold from the solution, gets the real solution to the original
    puzzle, and gets 1 BTC
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.36/39

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  37. Assignment
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.37/39

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  38. Assignment 6. “Cyber-Physical”
    Briefly describe your idea of combining self-driving cars with smart contracts
    A smart contract is the code and data stored and maintained on a
    censorship-resistant ledger (not necessarily a (legally valid) contract)
    Begin with 4 sentences (problem, why it is a problem, your startling
    sentence, its consequence)
    Deadline and how to submit
    Janurary 4, 2022 at 17:59 JST
    From Moodle (mandatory) — this time, we are using a Q&A forum
    So that your classmates can read your report, refer to it, and comment on it
    Optionally, you can also post to #assignments channel at Discord
    So that anyone in our Discord can read your report, refer to it, and comment on it
    Just plain text, and be concise, please
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.38/39

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  39. See You in 2022!
    Have a nice rest of 2021
    Chatting on Discord is always welcome!
    Lecture 12 : DeFi : Decentralized Finance — FinTech — Financial Innovation and the Internet 2021 Fall — 2021-12-10 – p.39/39

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