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CRYPTOCURRENCYfor Artists &
Social ChangeThe Critical Engineering Working GroupWeise7 Studio | Berlin-NeuköllnAUGUST 2017
Summary
In this 2-day workshop, students will receive an introduction to the cryptocurrency ecosystem and how "programmable money" can be a valuable tool – or even source of inspiration – for art, activism and beyond. They will also learn about potential use cases beyond money and the socioeconomic implications of decentralised, algorithmic governance. Infrastructural and environmental costs of cryptocurrencies will be addressed and compared, with a view to sustainable futures.
https://criticalengineering.org/intensives/2017/crypto
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WORKSHOP SCHEDULE
● Cryptocurrency 101▪ The History of Cryptocurrency▪ Cryptographic primitives, Merkle trees,
and Public Key Infrastructure▪ Centralised vs. Distributed vs.
Decentralised Networks▪ Crypto-Economics
Activity: How to use cryptocurrencies▪ Installing wallets▪ Making back-ups▪ Acquiring cryptocurrencies▪ Sending & receiving transactions▪ Purchasing goods and services▪ Setting up a full node (video)
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● Crypto-Artists▪ Visual Art (memes, comics, etc)▪ Music▪ Puzzles
● Social Change▪ Implications for…
▫ Banking▫ Employment (esp. salary)▫ Academic Research▫ Identity & Governance▫ Internet Content (esp. art and
investigative journalism)▫ Environment & Renewable Energy
Activity: Creating World Citizen IDs
▪
Disclosure: This presentation contains no paid product placement, promotion, or endorsement.
Chris EllisFounder of ProTipCommunity Liaison at Bitfinex
@MrChrisEllis
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▹ Microentrepreneur, developer, photographer, investigative journalist
▹ ProTip, a open source micropayment wallet “by artists, for artists”
Janine RömerApplied crypto, information security acolyte & researcher
@J9Roem
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▹ Writes about privacy, counter-surveillance, cryptocurrencies, wandering
▹ Coined “revision-controlled journalism”
Cryptocurrency 1011. The History of Cryptocurrency “Global Disruption” by @cryptograffiti
How do we make a private, secure, decentralised, digital currency?
Private: Not issued or controlled by a governmentSecure: “Coins” aren’t easily counterfeited or stolen; transactions can’t be reversed or double-spentDecentralised: No centralised authority (public or private) who controls all ownership, issuance, participation, or transaction activityDigital: No physical manifestation, fully electronic, interoperable, but at the same time scarce
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“
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Cypherpunks● Variant of “cyberpunk” (origin: ‘60s/’70s) -‘The underground of the electronic society’● Related: “crypto-anarchist” (origin: late ‘80s)
1990s: advocates for the use of cryptography as a tool for social change and expression“Cypherpunks Mailing List” (1992)
Fought export controls which regarded crypto as ‘weaponry’ (U.S.: “auxiliary military equipment”)
“ … Privacy in an open society requires anonymous transaction systems. Until now, cash has been the primary such system. An anonymous transaction system is not a secret transaction system. An anonymous system empowers individuals to reveal their identity when desired and only when desired; this is the essence of privacy.
We the Cypherpunks are dedicated to building anonymous systems. We are defending our privacy with cryptography, with anonymous mail forwarding systems, with digital signatures, and with electronic money.
“A Cypherpunk’s Manifesto” by Eric Hughes (March 1993)10
Cryptocurrencies are the latest innovation to come out of more than 40 years of cryptography research…
▪ “New Directions in Cryptography” by Whitfield Diffie & Martin E. Hellman (1976)
▪ “Secure Communications Over Insecure Channels” by Ralph C. Merkle (1978)
▪ “Untraceable Electronic Mail, Return Addresses, and Digital Pseudonyms” by David Chaum (1981)
▪ “Elliptic Curve Cryptosystems” by Neal Koblitz (1987)▪ “Pretty Good Privacy” by Phil Zimmermann (1991)▪ “How to Leak A Secret” by Ron Rivest, et al. (2001)
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“Bitcoin’s Academic Pedigree” by Arvind Narayanan & Jeremy ClarkVolume 15, Issue 4 of ACMQueue - August 29th 2017
Some time ago one of us returned from a brief vacation, only to find 241 messages in our reader. While junk mail has long been a nuisance in hard (snail) mail, we believe that electronic junk mail presents a much greater problem. In particular, the ease and low cost of sending electronic mail, and in particular the simplicity of sending the same message to many parties, all but invite abuse. In this paper we suggest a computational approach to combatting the proliferation of electronic mail. ▪ “Pricing via processing or combatting junk mail”
(1992) by Cynthia Dwork & Moni Naor13
Hashcash - Adam Back (March 1997) A proof-of-work system used to limit email spam▪ An “anti-spam exemption mechanism” & “plugin
software for mailers which adds hashcash stamps to sent email” headers as proof.
▪ Stamps are created using a “negligible” amount of CPU work to look for partial SHA1 hash collisions on strings created from recipient email addresses.
▪ CPU work not “negligible” for spammers.
More: http://www.cypherspace.org/adam/ 14
Conceptual precursors to Bitcoin ▪ “DigiCash” by David Chaum (1990-2002)▪ “b-money” by Wei Dai (November 1998)▪ “BitGold” by Nick Szabo (1998-2005)▪ “RPOW” by Hal Finney (August 2004)
Pegged to other currencies (dollar, euro) or commodities (gold)▪ “e-gold” by Gold & Silver Reserve Inc. (1996-2013)▪ “Liberty Reserve” by Arthur Budovsky (2006-2013)
“It would be very nice if there were a protocol whereby unforgeably costly bits could be created online with minimal dependence on trusted third parties, and then securely stored, transferred, and assayed with similar minimal trust.” - Nick Szabo
More: http://nakamotoinstitute.org/literature/ 15
RPOW - Hal Finney (August 2004) ▪ “This system receives hashcash as a Proof of Work
(POW) token, and in exchange creates RSA-signed tokens which I call Reusable Proof of Work (RPOW) tokens. RPOWs can then be transferred from person to person and exchanged for new RPOWs at each step. Each RPOW or POW token can only be used once but since it gives birth to a new one, it is as though the same token can be handed from person to person.
More: http://nakamotoinstitute.org/finney/rpow/faqs.html 16
itcoinA Peer-to-Peer Electronic Cash System
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“In this paper, we propose a solution to the double-spending problem using a peer-to-peer distributed timestamp server to generate computational proof of the chronological order of transactions. The system is secure as long as honest nodes collectively control more CPU power than any cooperating group of attacker nodes.” - Satoshi Nakamoto
https://bitcoin.org/bitcoin.pdf
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A transaction within block #138725 (July 30th 2011) includes a tribute to Len Sassaman and an ASCII art image of Ben Bernanke, the former Chairman of the Federal Reserve.
The OP_RETURN script opcode (added in March 2014) is used to “burn” bitcoins - i.e. render them unspendable - and store arbitrary data such as messages or links.
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BitBonkers A Bitcoin Blockchain Transaction Visualisation
by @Pigloo
A Next-Generation Smart Contract and Decentralized Application Platform
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“What Ethereum intends to provide is a blockchain with a built-in fully fledged Turing-complete programming language that can be used to create ‘contracts,’ that can be used to encode arbitrary state transition functions, allowing users to create any of the systems described above, as well as many others that we have not yet imagined, simply by writing up the logic in a few lines of code.” - Vitalik Buterin
https://github.com/ethereum/wiki/wiki/White-Paper
Ethereum
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Privacy-Focused Cryptocurrencies
CryptoNote ring signatures forring confidential transactions
Stealth addresses (dual-key for either spending or “viewing,” i.e. removing unlinkability protection)
RingCTs will be mandatory after the upcoming Sept. hard fork.
Dynamic block size & dynamic fee transaction fee system based on demand
“Excessive” block size increases are penalised based on a quadratic function
Zero-knowledge proofs called zk-SNARKs (“zero-knowledge succinct non-interactive arguments of knowledge”)
Shielded addresses (optional) hide: sender, receiver, balance
Can also be made transparent later
More: zk-SNARKs - Under the Hood
2. Cryptographic Primitives, Merkle Trees, and Public Key Infrastructure
Cryptocurrency 101
“Pot o’ Bitcoin” by @phneep
What is a cryptocurrency?
A digital currency that utilizes cryptographic technologies such as hash functions, digital signatures, and public key infrastructure to provide security & anti-counterfeiting measures.
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- The Oxford English Dictionary
24 Source: https://en.oxforddictionaries.com/definition/cryptocurrency
“Bitcoin does not use encryption… [it] is not an essential part of Bitcoin’s technology.
- Pieter Wuille (@pwuille), Bitcoin Core developer
25 Source: https://www.quora.com/How-does-Bitcoin-encryption-work
Challenging Questions:Bitcoin as an anchor for defining “cryptocurrency”
1. Should pre-Bitcoin digital currencies, such as Chaum’s “DigiCash,” still be considered cryptocurrencies?
2. Should post-Bitcoin cryptocurrencies which don’t use a blockchain, such as IOTA, still be considered cryptocurrencies?
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The Cryptographic Primitives - Hash Functions
One-way, key-less cryptographic algorithms that create message digests or digital fingerprintsExample: echo engineer | openssl sha256 produces the following hash value...
37279d6adeb3647a9332573137de80e56a07ff18dec3a09cbb0bea18a5a1452c
Provides a measure of the string’s or file’s integrity
Useful in a commitment scheme (“commit now, reveal later”) or in the secure storage of user credentials
28Image: © Edward W. Felton from “Bitcoin and Cryptocurrency Technologies” via Coursera Prof. Computer Science at Princeton University - Assistant Professor: Arvind Narayanan
Comparison - Hash Functions
CRYPTOCURRENCY HASH FUNCTION CRYPTOCURRENCY HASH
FUNCTION
Bitcoin SHA-256RIPEMD-160 Ethereum Keccak-256
(Mining: Ethash)
Litecoin Scrypt(“S-Crypt”) Monero CryptoNight
Zcash Blake2b(Mining: Equihash) IOTA Curl
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30Image: © Edward W. Felton from “Bitcoin and Cryptocurrency Technologies” via Coursera Prof. Computer Science at Princeton University - Assistant Professor: Arvind Narayanan
Because the hash of the previous block is always included in the next block, this effectively creates a tamper-evident log - where a block which does not correctly reference the hash of previous blocks will be seen as invalid and discarded.
31 Images: © Edward W. Felton; Satoshi Nakamoto
“Transactions are hashed in a Merkle Tree, with only the root included in the block's hash. Old blocks can then be compacted by stubbing off branches of the tree. The interior hashes do not need to be stored.” - Satoshi Nakamoto
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The Cryptographic Primitives - Digital SignaturesA cryptographic scheme where a signing algorithm uses a secret key to generate an electronic signature of a given plaintext message
A signature verifying algorithm is used to confirm authenticity.
S = encrypt(sha256(M), Kpriv)
Example: Formula for generating signatures (S). Bitcoin implements digital signing of transactions with the Elliptic Curve Digital Signature Algorithm (ECDSA) - specifically the secp256k1 curve.
Comparison - Digital Signature Algos
CRYPTOCURRENCY SIGNATUREALGORITHM CRYPTOCURRENCY SIGNATURE
ALGORITHM
Bitcoin ECDSA(secp256k1 curve) Ethereum ECDSA
(secp256k1 curve)
Litecoin ECDSA(secp256k1 curve) Monero EdDSA
(Ed25519)
Zcash EdDSA(Ed25519) IOTA Lamport*
(Winternitz)
33*Hash-based one-time signatures
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Public key cryptography
Bob sends locks to his friends. Anyone can have a copy.Bob sends his public key to friends. Anyone can have a copy.
PublicPrivate
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Public key cryptography
Bob’s friends use the locks to securely close the boxes.Bob’s friends use his public key to encrypt messages.
PublicPrivate
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Public key cryptography
Bob’s friends ship the locked boxes to him.Bob’s friends send the encrypted messages to him.
PublicPrivate
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Public key cryptography
Only Bob has the key to unlock the box & see the items.Only Bob has the secret key to decrypt & read the messages.
PublicPrivate
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Public key cryptography
If Bob has their locks, he sends locked boxes back.If Bob has their public keys, he sends encrypted messages back.
PublicPrivate
Private
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Difference between SKC, PKC, and Hash Functions
Image Source: Gary C. Kessler’s Overview ofCryptography - “Types of Cryptographic Algorithms”
“Realizing the Potential of Blockchain”
by Don Tapscott and Alex Tapscott (The Tapscott Group)
World Economic Forum © 2017 – All rights reserved40 Source: http://www3.weforum.org/docs/WEF_Realizing_Potential_Blockchain.pdf
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A two-key safety deposit box...
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Bitcoin Address≠
Public Key
Addresses are technically not public keys, even though they
are practically used as such.
They are hashes of the public key (using the SHA256 and RIPEMD160
hash algorithms), encoded in a Base58 format (alphanumeric) to make them more compact, easier to read or type.
Obfuscating the public key this way, until funds are spent, has security benefits (if ECDSA or the particular
ECDSA curve is cracked).Source: https://github.com/bitcoinbook/bitcoinbook/blob/second_edition/ch04.asciidoc
Chain Blocksof
43 Source: https://twitter.com/petertoddbtc/status/877580303279079424
What is a blockchain?
A state transition system in the form of a hash-linked data structure that is extended, verified, synchronized, and maintained through cryptographic puzzle-solving and game-theoretical consensus mechanisms.
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What about...
Decentralised Secure Immutable Censorship-Resistant ?
These words are often spoken of as inherent properties of blockchains.
But they are not inherent. They are emergent.45
Emergent properties
Complex systems are composed of simple, individual components which are free to (inter)act in nonlinear ways, without centralised controllers.
Emergent properties are the outcome of these individual components (inter)acting in a systematic way.
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Emergent properties
Bipedalism = several body systems evolving over time, responding to environmental changes
Decentralisation, etc. = several groups of people adhering to the same consensus mechanisms and (inter)acting as stewards of a particular public, open-source, open-access database
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3. Centralised vs. Distributed vs. Decentralised
Cryptocurrency 101Bitcoin Puzzle by @coin_artist
Topology: Decentralised vs. Distributed
▪ “On Distributed Communications” by Paul Baran (August 1964) Source: https://www.rand.org/content/dam/rand/pubs/research_memoranda/2006/RM3420.pdf
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Evolving TerminologyPaige Peterson (@ioptio)Communications at Zcash Companyformerly at MaidSafe
CC-BY-SA 4.050
Topology: Hybrid vs. Pure P2P
▪ Source: https://blog.maidsafe.net/2016/01/10/evolving-terminology-pt-2/
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Centralised Admin Points (Coordinating Entities)
▪ Registration▪ Peer Discovery
Open Access
Open Source
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A Game (Theory) About Trust - http://ncase.me/trust/ Art & Game by: Nicky Case (@ncasenmare) - Music: “Bleu” by Komiku (CC0)
4. Crypto-Economics
Cryptocurrency 101“Cryptocurrencies” by @cryptograffiti
“ Cryptocurrency is an impressive technical achievement, but it remains a monetary experiment. Even if cryptocurrencies survive, they may not fully displace fiat currencies… They provide an interesting new perspective from which to view economic questions surrounding currency governance, the characteristics of money, the political economy of financial intermediaries, and the nature of currency competition.”
- Eli Dourado and Jerry BritoThe New Palgrave Dictionary of Economics54
Image from: “Comparing the Cryptocurrency Bull Market & the Dotcom Bubble.”
The size of the cryptocurrency market is still relatively small…
Update: August 2017 All cryptocurrencies: $153 BBitcoin: $70 BEthereum: $30 BLitecoin: $2.5 BMonero: $1.3 BZcash: $470 million
Dotcom Bubble: $6.7 trillion
“ The great thing that came out of Bitcoin was the realisation that we (the people) could do our own money . It doesn’t matter who we are. We didn’t have to go and get permission. We didn’t have to run an ad, we didn’t have to pay a fee, we didn’t have to follow a rule-book… This is a huge opportunity to tell everybody that innovation belongs to us… if we can bring the community together to make it happen. That is a viable option now.”
- Ian Grigg in Ulterior States56
Comparison - Size of Blockchain
CRYPTOCURRENCY CURRENTSIZE CRYPTOCURRENCY SUPPLY
CAP
Bitcoin(Genesis: 2009-01-09)
153 Gb Ethereum(Genesis: 2015-07-30)
117.6 Gb
Litecoin(Genesis: 2011-10-08)
8.77 Gb Monero(Genesis: 2014-04-08)
24.08 Gb
Zcash(Genesis: 2016-10-28)
6.16 Gb IOTA* ?
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*IOTA uses a “blockless” distributed ledger.Date: August 25th 2017 Source: https://bitinfocharts.com/
Comparison - Supply Cap
CRYPTOCURRENCY SUPPLYCAP CRYPTOCURRENCY SUPPLY
CAP
Bitcoin 21 million Ethereum none
Litecoin 84 million Monerosomewhat
(18.3 million, then <1% decreasing emission
rate onwards)
Zcash 21 million IOTA ~2.78 billion
58Source: https://coinmarketcap.com/
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Why 21 million bitcoins?Block time + decreasing block reward cycle1 block every 10 minutes (avg) = 6 blocks every hour
144 blocks every day
~52,560 blocks every yearx 4 years per block reward cycle
-------------------------------~210,000
x 100 (sum of block reward amounts)= 21 million bitcoins
Image from: “Peer to Peer - Since the Beginning” by @rockbarcellos
ACTIVITY:1. Install wallets2. Make backups3. Buy / receive
cryptocurrencies4. Send transactions5. Buy goods & services6. Setting up a full node
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Social Change
“Mobile Seurat” by @phneep - remix of Georges Seurat
The implications of cryptocurrencies for...
▪ Banking▪ Employment (esp. Salary)▪ Academic Research▪ Internet Content (esp. journalism)▪ Environment & Renewable Energy
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Banking● Central(ised) banks will have significantly less power to…
○ Control transactions & savings (regardless of socioeconomic status)
○ Force economic stimulus & contraction○ Export national / regional interests & influence via
financial neocolonialism● Increased ability and necessity for ordinary people to...
○ Have financial autonomy○ Establish basic understanding of the financial system○ Adopt informational & operational security practices
● The “un-banked” / “under-banked” could enter national & global economies sooner (permissionless access to finance)
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The WikiLeaks Banking Blockade
“Since 7th December 2010 an arbitrary and unlawful financial blockade has been
imposed by Bank of America, VISA, MasterCard, PayPal and Western Union.”
● Excerpt from ‘Ulterior States’● WikiLeaks’ Mastercard Commercial Parody● Satoshi Nakamoto on WikiLeaks adopting bitcoin (analysis)● Bitcoin in ‘Cypherpunks, Freedom, and the Future of the Internet’● WikiLeaks takes donations in Bitcoin, Litecoin, Zcash, and Monero
“Bitcoin is the first truly successful implementation of a classic cypherpunk concept: the cryptographic digital currency.”
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“Insecurities and Misconceptions on Privacy-Enhancing Tools,” on mobile device & network security regarding cryptocurrencies
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Employment (esp. Salary)
● Better payment terms for suppliers & remote workers○ Monthly or weekly time-scale for distribution of salaries
could be replaced with daily, hourly, or minute-by-minute micropayments
○ International transfers to remote workers less complicated (re: identity documentation) & with faster clearance times
● Smaller fees & commission taken from remittance payments○ Western Union would lose monopoly
● New multi-disciplinary jobs created○ Finance + Tech + Economics + Law / Dispute Resolution
● Organisational structure (DAOs)
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Academic Research● Greater incentive to explore:
○ Applied cryptography○ Consensus algorithms &
dispute resolution○ Market behaviour,
macroeconomics (esp. with real-time data)
○ New funding models for academic research
“Peer-to-Peer Review: The State of Academic Bitcoin Research 2015” by Brett Scott (@Suitpossum)
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Internet Content● No 3rd party services needed for subscriptions or donations● No need for either sender or receiver to provide identity● More secure, less invasive than ad + surveillance revenue model● Micropayments: no minimum threshold (unlike credit cards)
Uses Beyond Money
● Timestamping of documents; proof-of-concept & ownership
ex. Revision-controlled journalism ex. Academic certificates on the Bitcoin blockchain
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“Brave Browser, BATs, and the Attention Economy”
Our Interview with Brendan Eich
Brave Payments is a ‘centralised but open-source reconciliation system.’
Crypto-Puzzles
▪ A new way to create, value, fund, and engage with art
▪ A creative way to educate people about abstract concepts in cryptography
“Digital treasure hunts using art” @coin_artist72
A piece of art in the form of a human-solvable puzzle or maze, hiding a cryptocurrency reward
via @Archillect
Music
▪ Ben Prunty
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Cipher: the Score for Banking on Bitcoin
Album Cover: Sylvia Ritter
Tinkerer’s Anthem▪ Proof-of-Beats
Bitcoin Jingle▪ Tatiana Moroz
Fashion
▪ Samson Mow
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Bitcoin Hats
Designer: Samson Mow
Cryptocurrency Apparel
▪ Cryptograffiti
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Environment & Renewable Energy
“Bitcoin Exahash Figures” by @phneep
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“Bitcoin Mining Documentary” (Satire) by @YourBTCC
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*Assuming those energy consumption estimates are accurate, and you squeezed the entire global BTC network & mining operations into Great Britain & Northern Ireland :P
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Environment & Renewable Energy● “Energy consumption” in Bitcoin mining is hard to measure
○ Mining industry operations not well known (anonymity)○ Efficiency of equipment varies & often improves○ Generation source of electricity varies
● Energy consumption in the traditional banking system is even harder to measure (particularly its externalities)○ ATMs; local, regional, and national banking branch buildings○ Ancillary support services (data centers, call centers, etc.)○ Stock exchanges & other trading hubs (high-speed)○ Financial management; identity fraud protection○ Mint bureaus (resources need to create notes & coins)○ Multi-decade conflict & wars, financed through debt system
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“As climate change becomes a more pressing concern for humanity every day, this huge level of energy use is difficult to justify for a currency wanting to improve on the current arrangement.”
Source: https://motherboard.vice.com/en_us/article/ae3p7e/bitcoin-is-unsustainable
80 Source: https://motherboard.vice.com/en_us/article/ae3p7e/bitcoin-is-unsustainable
Don’t bury the lead...
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“Three months living in a multi-petahash BTC mine in Kangding, Sichuan, China”
Eric Mu -- former CMO of HaoBTC (2015)
“Using cheap hydro-power and low-cost water-cooling system, this farm has achieved high ROI rate. Right now it generates 4.7 petahash/sec and according to our plan will max at 12P over the next three to four months period.”
Re-think this...Bitcoin is an incentive system...
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Bitcoin is a global, decentralised, open-access, thermodynamically-secured network, in which participants are incentivised through a game theoretical reward system to find the cheapest, most stable, and abundant energy sources.
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Operational costs of mining● Power supply● Internet service● Equipment: machines, racks, cables, cooling
system, maintenance and upgrades● Real-estate: buying or renting land & buildings ● Labor: training in cryptocurrency-related skills● Security (of building, of local network)
More: “Life Inside of China’s Massive and Remote Bitcoin Mines” by Quartz Media
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Proof-of-Work Cryptocurrencies - Incentives -
● Research into improving computer hardware efficiency & durability, microprocessing speed, & memory capacity
● Adoption & development of sustainable, renewable energy sources
Solar, hydro, wind…. geothermal?
ex. 14nm transistor extends shelf-life of mining equipment from months to years
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Geothermal Gold: Why Bitcoin Mines are Moving to Iceland
Anthony Cuthbertson -- for International Business Times (2014)
“Iceland, with its 100% renewable energy, perma-cool temperatures and data cable connections to both sides of the Atlantic, is a ‘sweet-spot’ location for companies to base their massive power-consuming, heat-producing machines. Among them are bitcoin miners.”
“ One of the really interesting opportunities is renewable energy that has cycles of demand in it. For example, you have production from solar or wind or hydro; that production is fixed, you get x megawatt hours coming out of your pipe all the time. But the consumption in the distribution network changes over the day. What do you do with the excess capacity?
-Andreas Antonopoulos
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Image from: “Digest of UK Energy Statistics - Chapter 5: Electricity”
Adoption of RenewablesUK Energy Stats “Renewables generation trebled since 2010” (pg 117).
24.5% of electricity supply
“Domestic electricity generation by households with micro-generation units - such as solar photovoltaic panels - increased sharply… Self-produced electricity still accounts for only 1.3 per cent of domestic consumption” (pg 115).
“ This is also a strong point in the current Bitcoin blocksize debate where those against large blocksizes argue that the larger the bitcoin blockchain is, the more resources a node requires thus removing ability for some people to run them and effectively pushing it towards a less decentralized network and a greater potential for centralizing ownership.
-Paige Peterson
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89 ‘SegWit activating on Bitcoin’ by @coinsiglier
Segregated Witness
OPENDIMESmall, disposable, USB hardware wallets that can be used ‘like cash’
Stores private key, must be unsealed to spend on the Bitcoin blockchain
For direct hand-to-hand “off-chain” transactions
No limit or pre-defined amount needed to use
@OPENDIME
World Citizen IDsCreating Affordable Decentralised Passport Services Using Available Cryptographic Tools
91https://github.com/MrChrisJ/World-Citizenship
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“I wanted to create a voluntary ID system in which my proof of existence could be backed by a social network of my choosing.
- Chris Ellis, WIRED Magazine (October 2014)
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Malavika JayaramFellow at the Berkman Center for Internet and Society at Harvard University
Contrast:
Biometric ID Cards by the Billion Experiences with Aadhaar in India, or what possibly could go wrong #SHA2017 - Day 5
“A lot of people here see this as, ‘Well, it’s an Indian project. Who cares? What does this have to do with me?’ It has everything to do with you, because my government is going to be selling it to your government!”
Identity on a Blockchain?“Empower individuals to reveal their identity when desired and only when desired...”
▪ Pseudonymous - not tied to a public identity▪ Vanitygen addresses - embedding identity
into transactions via personalised addresses▪ Namecoin - fork of Bitcoin; identity systems,
DNS registration & track ownership of assets95
96 Proof-of-Visit digital souvenirs - https://proofofvisit.com/ @ProofofVisit | Created by @_myveryown
FINALE: Let’s Review Some ConceptsCypherpunkAn advocate for the use of cryptography as a tool for social change and expression(slide #8)
CryptocurrencyA digital currency that utilizes cryptographic technologies to provide security & anti-counterfeiting measures(slide #23)
Hash FunctionA one-way, key-less cryptographic algorithm that creates message digests or digital fingerprints (slide #27)
Digital SignatureA cryptographic scheme where a signing algorithm uses a secret key to generate an electronic signature of a given plaintext message; for verifying authenticity(slide #32)
Public Key CryptographyAn asymmetric, two-key cryptosystem where one key (public) encrypts the plaintext inputs & the other key (private) decrypts the ciphertext outputs(slide #34 - 39)
BlockchainA state transition system in the form of a hash-linked data structure that is extended, verified, synchronized, and maintained through cryptographic puzzle-solving and game-theoretical consensus mechanisms
(slide #43 - 47)97
CREDITS & RESOURCESThank you to Critical Engineering for hosting us!
▪ Slide templates: SlidesCarnival (CC-BY)▪ Crypto-Artists: @cryptograffiti, @phneep,
@coin_artist, @TomerKantor (Ulterior States), @rockbarcellos, @coinsiglieri, @btcArtGallery, @Pigloo, @benprunty, @queentatiana (music)
This presentation is licensed underFind us at: chrisellis.me/ einzelgaengerinmotte.wordpress.com
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CREDITS & OTHER RESOURCES Learn more about cryptocurrencies:
▪ “Mastering Bitcoin” by @aantonop▪ Third Key Solutions with @pamelawjd▪ News: Bitcoin Magazine @BitcoinMagazine▪ Blog: ‘Unenumerated’ by @NickSzabo4▪ Explainers: Coin Center @coincenter
▫ “How Cryptocurrencies Work” by @3Blue1Brown▫ “Bitcoin Explained (with Emoji)” by @_tessr
▪ Collection: Bitcoin Resources by @lopp▪ Edu: Introduction to Digital Currency - University of Nicosia
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DANKE / THANKS!Any questions?
If you would like to participate in any future Critical Engineering workshops, please subscribe to the mailing list.
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