Support the show, consider donating: 14PRgGymfhzY19Jw7x3T9DrXD5Jjxo76JV (http://bit.ly/2hgRr1l) One of the shortcomings of decentralized smart contracts is their inability to retrieve information from the outside world. The deterministic nature of Etehreum-style blockchains makes it impossible for them to incorporate functions allowing them to do things such as make API calls to websites and data feeds. Though oracles are often cited as the solution to this problem, they require users to place a high level of trust in their operators, a model which would undermine the very nature of a decentralized smart contract. Ari Juels, a Professor at Cornell Tech (Jacobs Institute) and former Chief Scientist of RSA, joins us to discuss his work on Authenticated Data Feeds for Smart Contracts. These 'Town Crier' feeds would act as bridges between smart contracts and websites, srapping data over TLS and feeding to to a smart contract. Relying on sophisticated hardware enclave technology (Intel SGX), one who uses a Town Crier feed would not need to trust its operator as code execution would be guaranteed signed by the hardware. Topics discussed in this episode: - Ari's background in cryptography and cryptocurrencies - The pain points with oracles as we describe them today - The idea behind Authenticated Data Feeds - The hardware and software architecture of the Authenticated Data Feed model and how hardware isolation works - How Authenticated Data Feeds could be used to create criminal smart contracts - The differents ways in which criminals could use Authenticated Data Feeds to release bounties for crimes such as private key theft or even murder - Countermeasures which may prove effective in fighting criminal smart contracts - The Initiative For Cryptocurrencies & Contracts (IC3) and its raison d'être Links mentioned in this episode: - Ari Juels' website: http://www.arijuels.com - Town Crier: An Authenticated Data Feed for Smart Contracts (white paper): http://www.initc3.org/files/tc.pdf - The Ring of Gyges: Investigating the Future of Criminal Smart Contracts (white paper): http://www.initc3.org/files/Gyges.pdf - IC3 - The Initiative For Cryptocurrencies & Contracts: http://www.initc3.org/ Sponsors: - Jaxx: Wallets that Unify the Blockchain Experience Across Devices - http://jaxx.io Watch or listen, Epicenter is available wherever you get your podcasts. Epicenter is hosted by Brian Fabian Crain, Sébastien Couture & Meher Roy.

Today our guest is Mike Hearn who many of you are familiar with. He's one of the first Bitcoin users and the developer of BitcoinJ, a Java library used by a number of popular Bitcoin wallets such as the Android wallet, Multibit and Hive. Until recently he was working at Google and is now working full-time on Bitcoin, including an interesting crowdfunding platform called Lighthouse. Links: - Lighthouse: http://bit.ly/1nmV81R - Assurance contracts: http://bit.ly/1yovAIN - Arianna Simpson - Game Theory, Assurance Contracts, and Crowdfunding with Bitcoin: http://bit.ly/1lF1ziq - Venumeris: http://bit.ly/1icVLh7 - Mike Hearn talk at Coinscrum 2014 in London: http://bit.ly/1icVQRO - BitcoinJ: http://bit.ly/TaRzT0 - BitcoinJ on Github: http://bit.ly/1lCHcnp Show notes: http://epicenterbitcoin.com/eb-025 Running time: 1:17:34 Epicenter Bitcoin is hosted by Brian Fabian Crain & Sébastien Couture and is available on iTunes, SoundCloud, Mixcloud, Stitcher and other podcast aggregators. Website: http://epicenterbitcoin.com Subscribe: http://feed.epicenterbitcoin.com Subscribe to our Friday newsletter: http://epicenterbitcoin.com/newsletter Twitter: http://twitter.com/epicenterbtc Tip the show: http://epicenterbitcoin.com/tips