The idea of using the Bitcoin blockchain to represent and track the ownership of off-chain assets is almost as old as Bitcoin itself. One of the startups that is pursuing this vision is Berlin-based Ascribe, which allows creators to register (‘ascribe’), transfer and archive digital art. Ascribe CTO joined us for a fascinating discussion of their ambitious goals to enable a so-far elusive secondary market for digital art, help creators monetize their work and ultimately retrofit an entire ownership layer to the internet. Topics covered in this episode: Why ownership in the internet is broken How Ascribe wants to realize the vision of Project Xanadu of an internet with bi-directional links and baked-in copyrights How the SPOOL (Secure Public Online Ownership Ledger) protocol works The components of the Ascribe tech stack How Ascribe will crawl and similarity-match the entire internet to retrofit an internet of ownership Why Ascribe focuses first on the digital art market Episode links: Ascribe SPOOL Protocol Cointemporary Project Xanadu Wikipedia Rewiring the Internet for Ownership with Big Data and Blockchains Slides This episode is hosted by Brian Fabian Crain and Sébastien Couture. Show notes and listening options: epicenter.tv/078

Bitcoin’s approach to solving the double spending problem is to make a collusion and attack on the network prohibitively expensive. One of the main factors that will determine Bitcoin’s chance of survival in the long-term is whether the behavior that maximizes the profits of miners contributes to or sabotages the health of the network. The game theory that determines this is complex and our understanding of it still incomplete. But research is increasing and two people who have been at the forefront of this work are , a professor in computer science at Cornell University, and Ittay Eyal, a post-doc at the same department. They joined us for a fascinating discussion of their work on ‘selfish mining’, the incetive structure that underlies Bitcoin and their recent positive conclusions from the Miner’s Dilemma. Topics covered in this episode: Emin Gün Sirer’s early interest in cryptocurrencies and work on a cryptocurrency to incentivize bittorrent users in 2004 What selfish mining is and how miners could profit from withholding blocks How an attacker would execute a selfish mining attack Why the miner’s dilemma implies that the equilibrium might be small mining pools Why the lack of security of clients and servers is holding back adoption Episode links: Selfish Mining paper (PDF) Miner's Dilemma blog post Miner's Dilemma paper (PDF) Hacking, Distributed Meni Rosenfeld's paper on mining pool reward systems (PDF) This episode is hosted by Brian Fabian Crain and Sébastien Couture. Show notes and listening options: epicenter.tv/076