Blockchain Overview

Blockchain計財 15 楊佑濬經濟 16 吳羿蓁

Blockchain?

Let‘s start from a transaction

http://spectrum.ieee.org/image/MjA3NDM1OA

Three steps of issuing a transaction Identify the as-yet unspent Bitcoin that you want to move Prove that you are entitled to move it Set the next private & public keys for the next owner of these

specified BTCs

Blockchain???

Coinbase

Transactions

Hash Link

Hash Link

Mining / Confirming Block & TxReceive TxWrite on block

Underlying Assumptions Coinbases are random distributed Encrypting methods are unbreakable in reality

51% attack Mining-Hacking Dilemma People want to use Bitcoins

Benefits Fast confirmation Decentralization

Eliminate human control Remove the need for middleman

Good protection to privacy but still traceable Low probability of faking No default risk Information contains in block

does not limited to transactions

Coinbase

Information

Application Implementations New Cyber-coins(or altcoin)

Namecoin Ethereum Litecoin …

Based on Bitcoin Blockchain Counterparty Protocoll Sidechains

Application Implementations

Using Bitcoin Using Other Cyber-currency

Using Bitcoin Blockchain Bitcoin Mastercoin,

Counterparty

Using Separate Blockchain Sidechain Namecoin,

Ethereum

https://www.coingecko.com/en

Other Cyber-currencies(Altcoins)

Beyond the Original Blockchain

http://www.coindesk.com/blockchain-application-stack/

Counterparty Protocol Change BTC to XCP as a token

Burn BTC in exchange a XCP Create divisible and callable assets Broadcast everything to Bitcoin Blockchain

So everything here have the benefits of blockchain

http://blockscan.com/

Bitcoin Blockchain

BTC

XCP

Burn BTC

AssetsIssue

Dividends

DistributeBro

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Broadcast

Sidechains Use the standard bitcoin “three-step” transaction.

Immobilize bitcoins whilst they’re “on” the sidechain. The rules can be whatever those running that sidechain want

them to be. Whoever is holding these coins on the sidechain can send

them back to the Bitcoin network By creating a special transaction on the sidechain that immobilizes the

bitcoins on the sidechain.

Frozenmessage

Blockchain Sidechain

Sidechains One-way pegging

Two-way pegging

blockchain sidechain

blockchain sidechain

Some Application Examples Namecoin in domain name ownership recording IoT using Blockchain NASDAQ using Blockchain in private shares transaction

Namecoin A decentralized open source information registration.

Based on the Bitcoin cryptocurrency. Different from the blockchains of Bitcoins.

Securely record and transfer arbitrary names (keys). Attach a value (data) to the names

up to 520 bytes, more in the future Transact namecoins, the digital currency (ℕ, NMC).

IoT using Blockchain

NASDAQ Linq Blockchain Used in part of the pre-IPO OTC market.

Relatively small market Originally using paper-pen-based or spreadsheet-based verified by lawyer

Powered by Chain Inc. Benefits

Fast settlement(10 mins) Transactions are clear

Limitations May exists some hackers simply want to destroy bitcoin

blockchain. Ten-minute Bitcoin’s block interval is too slow for some people

and may be longer in the future. Calculation power is depended on miners.

Conclusion It is hard to separate blockchain from Bitcoin Bitcoin would only be more and more important if we want to

build applications based on blockchain. Applications on blockchain are still far from complete, but on its

way. When the eco-system is large enough, no one sure if the Bitcoin

system is able to handle massive size of transactions.

http://www.appledaily.com.tw/appledaily/article/international/20160503/37193575/

References Bitcoin introduction

https://yowureport.com/%E5%85%A9%E5%B9%B42%E8%90%AC%E5%80%8D%E7%9A%84%E5%8D%87%E5%80%BC%EF%BC%8C%E6%9C%80%E5%88%92%E7%AE%97%E7%9A%84%E6%8A%95%E8%B3%87-%E6%B7%B1%E5%85%A5%E4%BA%86%E8%A7%A3-bitcoin/

http://www.soft4fun.net/tech/trend/bitcoin-mechanism.htm#axzz4489CyOkN

http://spectrum.ieee.org/image/MjA3NDM1OA Blockchain introduction

https://en.wikipedia.org/wiki/Block_chain_(database) https://en.bitcoin.it/wiki/Block https://bitcointalk.org/index.php?topic=112041.0

References Altcoins

https://www.coingecko.com/en Blochchain application

http://www.coindesk.com/blockchain-application-stack/ https://www.quora.com/What-are-non-Bitcoin-applications-of-blockchain-technology http://joel.mn/post/103546215249/the-blockchain-application-stack http://coinoutletatm.com/5-applications-of-the-blockchain-apart-from-currency/ https://azure.microsoft.com/en-gb/blog/ethereum-blockchain-as-a-service-now-on-azure/

Side-chain implementations https://

www.reddit.com/r/Bitcoin/comments/22vn4m/why_do_people_think_that_sidechains_are_going_to/cgqy5w6 https://www.blockstream.com/sidechains.pdf https://gendal.me/2014/10/26/a-simple-explanation-of-bitcoin-sidechains/ http://siliconangle.com/blog/2014/04/21/bitcoin-sidechains/ http://www.coindesk.com/bitcoin-core-developers-bitcoin-side-chains/

Reference Namecoin

http://namecoin.info/ IoT using Blockchain

http://postscapes.com/blockchains-and-the-internet-of-things NASDAQ Application

https://chain.com/about/ http://www.wsj.com/article_email/a-bitcoin-technology-gets-nasdaq-test-1

431296886-lMyQjAxMTE1MzEyMDQxNzAwWj http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-bl

ockchain-project/