What is your opinion on directed acyclic graphs (DAGs) and whether they can achieve the same level of decentralisation, security, and censorship resistance? DAGs are not vaporware, but the cryptocurrency projects using them mostly employ proof-of-stake (PoS) or proof-of-authority consensus mechanisms, which cannot be compared to proof-of-work (PoW) yet because they have not been tested at the same scale. PoW in Bitcoin, with a thermodynamic cost, will be hard to replace. Even though IOTA employs a PoW-type mechanism, they technically use proof-of-authority because IOTA is currently reliant on one special "Coordinator" node, run by their Foundation, to verify all transactions; if they were to shut it off today, we have no idea whether the other 'sub nodes' would be able to maintain its current level of security. We can begin to make real comparisons once it is no longer centralised. This is a question from the patron-only live Q&A which took place on January 27th 2018. If you want early-access to talks and a chance to participate in the monthly live Q&As with Andreas, become a patron: https://www.patreon.com/aantonop RELATED: Altcoins and the scaling debate - https://youtu.be/slbpdW-H3yk Do altcoins threaten to replace bitcoin? - https://youtu.be/w-V_5EWyU5c The Scaling Rites of Passage - https://youtu.be/rZi86_ovB3Y Scaling, trust, and trade-offs - https://youtu.be/vCxmHwqyJWU Scaling complex systems - https://youtu.be/dm9m1oQr6Ks Governance trade-offs in decentralised systems - https://youtu.be/dtwaW79Fj7c Governance and the transaction fee market - https://youtu.be/gdknUUVOdHU Unstoppable code - https://youtu.be/AQx3E3F8Kz4 We all started as critics - https://youtu.be/-jvefuVRwYA Why running a node is important - https://youtu.be/oX0Yrv-6jVs The new experimental science of consensus algorithms - https://youtu.be/6N5XlU7Iajk Security in proof-of-work vs. proof-of-stake - https://youtu.be/dstjlfW4-g8 Proof-of-Work (PoW), Proof-of-Stake (PoS), Delegated Proof-of-Stake (DPoS) - https://youtu.be/3W_3AQrQEOM Consensus with decentralized oracles and real-world variables - https://youtu.be/8bYmK6sZL00 Intrinsic vs. extrinsic assets - https://youtu.be/KDtfFNZy9xg What is mining? - https://youtu.be/t4p4iMqmxbQ Energy consumption - https://youtu.be/2T0OUIW89II Solar energy and mining in space - https://youtu.be/cusakcpa8AM What is the biggest threat? - https://youtu.be/1-XUbH1F0Os Immutability and Proof-of-Work: The Planetary Scale Digital Monument - https://youtu.be/rsLrJp6cLf4 Bitcoin: "Failing to Scale" - https://youtu.be/bFOFqNKKns0 Ethereum, ICOs, and Rocket Science - https://youtu.be/OWI5-AVndgk The Lion and the Shark: Divergent Evolution in Cryptocurrency - https://youtu.be/d0x6CtD8iq4 Andreas M. Antonopoulos is a technologist and serial entrepreneur who has become one of the most well-known and respected figures in bitcoin. Follow on Twitter: @aantonop https://twitter.com/aantonop Website: https://antonopoulos.com/ He is the author of two books: “Mastering Bitcoin,” published by O’Reilly Media and considered the best technical guide to bitcoin; “The Internet of Money,” a book about why bitcoin matters. THE INTERNET OF MONEY, v1: https://www.amazon.co.uk/Internet-Money-collection-Andreas-Antonopoulos/dp/1537000454/ref=asap_bc?ie=UTF8 [NEW] THE INTERNET OF MONEY, v2: https://www.amazon.com/Internet-Money-Andreas-M-Antonopoulos/dp/194791006X/ref=asap_bc?ie=UTF8 MASTERING BITCOIN: https://www.amazon.co.uk/Mastering-Bitcoin-Unlocking-Digital-Cryptocurrencies/dp/1449374042 [NEW] MASTERING BITCOIN, 2nd Edition: https://www.amazon.com/Mastering-Bitcoin-Programming-Open-Blockchain/dp/1491954388 Subscribe to the channel to learn more about Bitcoin & open blockchains! Music: "Unbounded" by Orfan (https://www.facebook.com/Orfan/) Outro Graphics: Phneep (http://www.phneep.com/) Outro Art: Rock Barcellos (http://www.rockincomics.com.br/)