zkLedger: privacy-preserving auditing for distributed ledgers Narula et al., NSDI'18 Somewhat similarly to Solidus that we looked at late last year, zkLedger (presumably this stands for zero-knowledge Ledger) provides transaction privacy for participants in a permissioned blockchain setting. zkLedger also has an extra trick up its sleeve: it provides rich and fully privacy-preserving auditing capabilities. ... Continue Reading

Towards a design philosophy for interoperable blockchain systems Hardjono et al., arXiv 2018 Once upon a time there were networks and inter-networking, which let carefully managed groups of computers talk to each other. Then with a capital "I" came the Internet, with design principles that ultimately enabled devices all over the world to interoperate. Like ... Continue Reading

A quantitative analysis of the impact of arbitrary blockchain content on Bitcoin Matzutt et al., FC’18 We’re leaving NDSS behind us now, and starting this week with a selection of papers from FC’18. First up is a really interesting analysis of what’s in the Bitcoin blockchain. But this isn’t your typical analysis of transactions, addresses, ... Continue Reading

Settling payments fast and private: efficient decentralized routing for path-based transactions Roos et al., NDSS’18 Peer-to-peer path-based-transaction (PBT) networks such as the Lightning Network address scalability, efficiency, and interoperability concerns with blockchains through off-chain transactions. They work by establishing decentralised chains of participants through which payments are routed. A PBT network builds on top of ... Continue Reading

Zeus: Analyzing safety of smart contracts Kalra et al., NDSS’18 I’m sure many readers of The Morning Paper are also relatively experienced programmers. So how does this challenge sound? I want you to write a program that has to run in a concurrent environment under Byzantine circumstances where any adversary can invoke your program with ... Continue Reading

Decentralization in Bitcoin and Ethereum networks Gencer et al., FC’18 I thought it would be fitting to round off this week’s selections by looking at the state of Bitcoin and Ethereum in practice. Today’s paper presents the results of a series of measurements of the respective networks, taken through 2016 and 2017. Ongoing research explores ... Continue Reading

SoK: Research perspectives and challenges for Bitcoin and cryptocurrency Bonneau et al., IEEE Security and Privacy, 2015 Part 2 : modifications, extensions, anonymity. Here’s the map for what we’ll be talking about today. We’ll discuss considerations for modifying and/or upgrading the way Bitcoin works, the world of altcoins, and uses beyond cryptocurrency. We’ll also touch ... Continue Reading

SoK: Research perspectives and challenges for Bitcoin and cryptocurrency Bonneau et al., IEEE Security and Privacy, 2015 Part 1 : core technology and the question of stability. Yesterday we took a look at consensus for blockchain-based systems. Together we’re going back in time a little further to 2015, where we find a broader survey of ... Continue Reading