비트코인: 금융의 인터넷 (bitcoin: the internet of money)

비트코인:�� 금융의�� 인터넷 (Bitcoin: The Internet of Money)

2015. 4. 23.

Prof. Sangkyu RhoGraduate School of Business

Seoul National University

http://www.slideshare.net/srho/bitcoin-the-internet-of-money-47354175

(CC BY-SA 3.0) Sangkyu Rho, SNU Business School

Who’s Sangkyu Rho?

Profession: • 서울대 경영대 교수 since 1995• 서울대 경영대 MBA부학장 from 2013 to 2014• 오가닉미디어랩(www.organicmedialab.com) 공동 운영 since 2013Interests: • Data & Knowledge• Social & Network Contacts: • [email protected] • Facebook: sangkyu.rho• LinkedIn: Sangkyu Rho• Twitter: @srho77

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“Bitcoin is Evil!”

http://krugman.blogs.nytimes.com/2013/12/28/bitcoin-is-evil/

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“It’s about the platform, not the currency, stupid!”

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http://thenextweb.com/insider/2014/02/15/bitcoin-platform-currency/


Bitcoin

Future of money?

What is mining?

Anonymous?

Why does it matters?

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Future of Money?

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What is Bitcoin?

Digital Currency• bitcoin

Fully distributed and decentralized payment network• We are the bank! (Peer-to-peer network)

Platform (OS) for financial innovations• Internet of Money

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Digital Currency

Bitcoin is a chain of digital signatures*

Is bitcoin money?

• A medium of exchange?

• A unit of account?

• A store of value?

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* Sathoshi Nakamoto, “Bitcoin: A Peer-to-Peer Electronic Cash System,” 2008


“We are the Bank!”

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Miner

UserOrganic Media Lab 2014

http://organicmedialab.com/2014/02/22/we-are-a-bank-in-bitcoin/


Internet of Money

Mechanism to prevent double spending without trusted 3rd parties such as banksContainers to store value (e.g., money, signatures, contracts, stocks, bonds, even cars)New ways to collaborateOpen sourced

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What is Mining?

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Trust By ComputationBlockchain • The public ledger of bitcoin transactions• A chain of blocks (beginning from the genesis block)• Can be browsed by blockchain browsers (e.g., http://

blockchain.info)

Proof of works• What miners do• To prevent bad guys from modifying blockchain

Public key encryption

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Block

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Organic Media Lab 2014


Bitcoin Mining: Proof of Work

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Finding nonce that satisfies the difficulty target

http://organicmedialab.com/2014/01/11/virtuous-cycle-of-bitcoin-mining/


Two Sides of Mining

To secure the blockchain• If good guys > bad guys

To supply new bitcoins• As awards to miners who first provide proof of

work.

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Virtuous Cycle of Bitcoin Mining

16http://organicmedialab.com/2014/01/11/virtuous-cycle-of-bitcoin-mining/


Anonymous?

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Bitcoin Transactions in Blockchain

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Bitcoin is a Link

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Bitcoin is a Link


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Bitcoin is a Network

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Bitcoin is a network


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Bitcoin Transactions are Pseudonymous

사적인 익명성• No private information is shared

공적인 투명성• Every transaction is traceable from the beginning

to the end.

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Why does it matter?

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Bet with a Friend


Me Friend

Another Friend

$100over a billiard game

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Can I trust my friends?


Solution in Bitcoin: Multi-signature Transactions*


Me Friend

Another Friend (Arbitrator)

2-of-3 signature account 1 BTC 1 BTC

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* https://bitcoinmagazine.com/11108/multisig-future-bitcoin/


Bitcoin as Platform (OS) for Innovation

“PC in 1975, the Internet in 1993, and Bitcoin in 2014” – Marc Andreessen

It is a “transport layer” for finance.

“Programmable money”

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Applications for BitcoinPayment Network

• International money transfer

• Banking the unbanked

• Microtransactions

Platform for Innovation

• Decentralized exchange for currencies and assets (e.g., Bitshares)

• Decentralized application platform (e.g., Ethereum)

• Bitcoin + IoT (e.g., IBM ADEPT)

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Conclusion

More than digital money

Much more transparent than we think

Disruptive innovation in financial industry

Innovative way of economic mass-collaborations

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Bonus: How Can I Use?

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What you need to knowBitcoin Exchange• Bitstamp, Mt. Gox (now bankrupt), …• Korbit

Bitcoin Wallet• Client: Multibit• Service: Coinbase, Blockchain

Bitcoin Transactions• Public key encryption• Digital signature

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Bitcoin Transactions


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Bitcoin Transactions

Bitcoin addresses are public keys

Bitcoin transactions are digital signatures

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(CC BY-SA 3.0) Sangkyu Rho, SNU Business School 34

http://organicmedialab.com/2014/02/20/bitcoin-addresses-transactions-and-wallets/

(CC BY-SA 3.0) Sangkyu Rho, SNU Business School 35

http://organicmedialab.com/2014/02/20/bitcoin-addresses-transactions-and-wallets/


What you have in your wallet?

Bitcoin?

Essentially, bitcoin addresses and matching private keys• Protect your wallet with a secure password• Backup your wallet data

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Recommended Readings노상규, “비트코인은 버블인가, 파괴적 혁신인가?,” http://organicmedialab.com/2014/01/06/bitcoin-as-disruptive-innovation/

윤지영, “연결이 지배하는 세상, 화폐의 필연적 진화,” http://organicmedialab.com/2014/02/05/inevitable-evolution-of-money/

윤지영, “비트코인, 우리가 은행이다,” http://organicmedialab.com/2014/02/22/we-are-a-bank-in-bitcoin/

노상규, “비트코인 채굴과 선순환 구조,” http://organicmedialab.com/2014/01/11/virtuous-cycle-of-bitcoin-mining/

노상규, “비트코인 주소, 거래, 그리고 지갑,” http://organicmedialab.com/2014/02/20/bitcoin-addresses-transactions-and-wallets/

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Any Questions?Visit: www.organicmedialab.com

E-mail: [email protected]: sangkyu.rhoLinkedIn: Sangkyu Rho

Twitter: @srho77

비트코인: 금융의 인터넷 (bitcoin: the internet of money)

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