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blockchain.html
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<!DOCTYPE html>
<html>
<head>
<title>Containers-pres</title>
<meta charset="utf-8">
<style>
@import url(https://fonts.googleapis.com/css?family=Yanone+Kaffeesatz);
@import url(https://fonts.googleapis.com/css?family=Droid+Serif:400,700,400italic);
@import url(https://fonts.googleapis.com/css?family=Ubuntu+Mono:400,700,400italic);
body { font-family: 'Droid Serif'; }
h1, h2, h3 {
font-family: 'Yanone Kaffeesatz';
font-weight: normal;
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.remark-code, .remark-inline-code { font-family: 'Ubuntu Mono'; }
</style>
</head>
<body>
<textarea id="source">
class: center, middle
# Blockchain
---
# Intro
George Angel
Infrastructure Architect
---
# What is it?
*Trusted distributed ledger*
Current model:
```
+---+ +---+ +---+
| A | <---> | B | <---> | C |
+---+ +---+ +---+
```
Unit: money, titles, deeds, music, art, scientific discoveries, intellectual property, and even votes
---
# What is it? (II)
With blockchain:
```
+---+ +---+
| A | <---> | C |
+---+ +---+
(bc) (bc)
```
Unit: money, titles, deeds, music, art, scientific discoveries, intellectual property, and even votes
---
# Background
Bitcoin (digital asset and payment system)
- decentralised
- peer-to-peer
- verified public distributed ledger
---
# Components
- Units (bitcoin)
- Blockchain (public ledger) [distributed database]
- Ownership (private/public keys)
- transactions (transfer of ownership)
- hashing of blocks (immutability)
- proof of work (mining [solve difficult arithmetic problems, to create a cost of establishing consensus])
---
# Smart Contracts - after the bitcoin
- Units (bitcoin)
- Blockchain (public ledger) [distributed database]
- Ownership (private/public keys)
- **transactions (transfer of ownership [and more])**
- hashing of blocks (immutability)
- proof of work (mining [solve difficult arithmetic problems, to create a cost of establishing consensus])
---
# Smart Contracts (II)
* data (code of the contract)
* permissions (ownership of contract/asset)
* workflow (order of acting/chain of contracts)
---
# Examples
* multichain (simple, a lot of people hack on it)
* ethereum (smart contract, popular in banking)
* Eris/Tendermint
* hyperledger - started by IBM, donated to Linux Foundation
* R3 Corda - over 50 banks + exchanges that a part of consirtium
- Wrote their own version from the ground up, the contracts are only held by the parties transacting
* BigChainDB [github](https://github.com/bigchaindb/bigchaindb)
---
# Ethereum
*Bitcoin 2.0*
- Built by the people who worked on bitcoin
- Uses smart contracts
- Platform currency: ether
---
# The Good Stuff
- no central control
- redundancy
- immutable
- secure
- visable
- pseudo-anonymous
- open source
- Two levels of trust:
* participants id
* transaction integrity
---
# Risks
- The DAO
* kickstarter in ethereum (my poor approximation)
* Raised 150Mil (the most successful crowfunding ever)
* 3.6 mil ether (~ $72 mil at the time of the hack) currently frozen
More info on the DAO hack: [link](https://medium.com/@pullnews/understanding-the-dao-hack-for-journalists-2312dd43e993#.90e7y8j6w)
---
# Limitations
- Size
* current size of bitcoin blockchain: ~ 88 GB (https://bitinfocharts.com/) [2016-06-29]
* size of ethereum blockchain: 16 GB [2016-06-10]
- Fixes
* Side channel (another blockchain along side that gets "folded" into the main blockchain)
* Sharding (distribute the blockchain between the participants)
---
# How can we use it?
*Ethereum is a solution in search of a problem*
</textarea>
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