class: center, middle # LINGI 2401 : Open Source strategy for software development Lionel Dricot lionel.dricot@uclouvain.be lionel@ploum.net @ploum - @ploum@mamot.fr --- class: center, middle #Blockchains (and why it's important) --- class: center, middle #Lemma 1 (technical) : merkle tree  ??? https://en.wikipedia.org/wiki/Merkle_tree --- class: center, middle #Lemma 2 (sociology) : intersubjective reality - Yuval Noah Harari : Sapiens and Homo Deus - Objective reality vs subjective reality - Examples of intersubjective reality: religions, countries, money… --- class: center, middle #Classical story of money - Limited supply - Fongibility - No double spending/creating money --- #Historical examples - Gold - Rai stones - Fiat money - Bank bills  ??? https://en.wikipedia.org/wiki/Rai_stones --- class: center, middle #Virtual money - Paypal - Every bank account ??? We are working just to increase a number in a a database, hoping that this number has some value. --- class: center, middle #Money vs Debt - Debt: the first 5000 years, by David Graeber ??? https://en.wikipedia.org/wiki/Debt:_The_First_5000_Years --- class: center, middle #How to implement decentralised virtual money? - Using lemma 1 --- class: center, middle #Blockchain - Distributed Ledger - Consensus algorithm - Need to be opensource by design ??? If not opensource, it is not a true blockchain. It cannot be distributed if not opensource. --- class: center, middle  --- class: center, middle #What should be the next block ? - Code is law --- class: center, middle #Governance --- class: center, middle #Forks - Accidental forks should be avoided - Voluntary forks should be possible --- class: center, middle #The Byzantine generals problem Lamport, Shostak et Pease 82 ??? https://people.eecs.berkeley.edu/~luca/cs174/byzantine.pdf --- class: center, middle #Sybil attacks --- class: center, middle #Proof of work (mining) Changing the Nonce in the block: 000000000000000000520aea43a637615c5ada8a2ef96a4d3a23a9bdd73c12d5 --- class: center, middle #Other consensus algorthim - Proof Of Stake - Delegated Proof Of Stake - Proof of space - … ??? Currently, none have been demonstrated as reliable and secure consensus algorithms. --- class: center, middle #Permissioned vs Permissionless ??? Permissioned blockchains are mainly marketing bullshit. Think about a huge excel spreadsheet which is very hard to maintain. --- class: center, middle #How to create value? - Using lemma 2 ??? If people start to see value in a virtual currency, it becomes the value. --- class: center, middle #Bitcoin - Satoshi Nakamoto, 2009 - The 15,000 BTC pizza, 2010 - First bubble to 30$ in 2011 - Second bubble to 1200$ in 2013 - Third bubble to 19000$ in 2017 --- class: center, middle #A word about the price - Market fixes the price. Market is a crowd. - Bear vs bull - Short vs long - HODL, trading, scalping ??? All of that applies to any exchanged value --- class: center, middle #Cryptocurrency vs ERC20 token ??? Cryptocurrency has its own blockchain (BTC, LTC, ETH,…) ERC20 is a standard smart-contract based on the Ethereum blockchain. --- class: center, middle #The vertical database problem - There's always a need for a human "translator" ??? Anecdote with containers, with administration (my own diploma here at University), with Proximus at home. --- class: center, middle #Blockchain is the first horizontal database --- class: center, middle #Consequences - Transparence - Accountability - Decentralisation ??? Accountability because having a private key is a synonym to an identity (even if that identity might be anonymous) --- class: center, middle #A world about decentralisation --- class: center, middle #Uncentralisability --- class: center, middle #Impact on the world? - Blockchains are a way to take a decentralised decision --- class: center, middle #Human institutions… …are only a way to take a decision ??? Families, countries, student cercles, sport team, federation… All are just intersubjective reality group built in order to take collective decisions in the name of the group. --- class: center, middle #Example 1 : Namecoin --- class: center, middle #Example 2 : ZeroNet --- class: center, middle #Example 3 : Ethereum and smart contracts --- class: center, middle #Example 4 : supply chain --- class: center, middle #Example 5 : project management ??? Colony.io, Aragon… --- class: center, middle #Example 6 : identity ??? What's identity anyway ? https://medium.com/humanizing-the-singularity/a-brief-history-of-digital-identity-9d6a773bf9f5 --- class: center, middle #Example 7 : democracy ??? Democracy.earth Liquid democracy --- class: center, middle #Bitcoin's blockchain The billions dollars bounty --- class: center, middle #Complex equilibrium - Developers - Nodes (users) - Miners - Business (exchanges) --- class: center, middle #An ecological disaster? --- class: center, middle #It might not be the case - Most mined electricity comes from wasted source - It might change the dynamic of the power market - What's the value of a distributed database ? ??? Currently, it is still an experiment. It's not about how much electricity it consumes but about the ratio CO2 emitted/usefulness. Which is currently very hard to quantify. --- class: center, middle #You cannot have no question --- class: center, middle #Let's imagine use cases together --- class: center, middle # Discussion time