This Week in Blockchain Research Issue #85
|zk Capital||Dec 2, 2020|
Paper of the Week:
In a universally composable framework, a global setup is intended to capture the ideal behavior of a primitive which is accessible by multiple protocols, allowing them to share state.
The ledger implemented by blockchain protocols such as Bitcoin is a representative example of such global setup, since the Bitcoin ledger is known to be useful in various scenarios.
Therefore, it has become increasingly popular to capture such ledgers as a global setup. One would hope that this allows one to make security statements about protocols that use such a global setup, e.g., a global ledger, which can then be automatically translated into the setting where the setup is replaced by a protocol implementing it, such as Bitcoin.
This work shows that the above reasoning is flawed and such a generic security-preserving replacement can only work under very (often unrealistic) strong conditions on the global setup.
For example, the composable security of Bitcoin, cast as realizing an ideal ledger such as the one by Badertscher et al., is not sufficient per se to allow us to replace the ledger by Bitcoin when used as a global setup and to expect that security statements that are made in the global ledger-hybrid world would be preserved.
On the positive side, this work provides characterizations of security statements for protocols that make use of global setups, for which the replacement is sound.
The results can be seen as a first guide on how to navigate the very tricky question of what constitutes a “good” global setup and how to use it in order to keep the modular protocol-design approach intact.
1. Paper Title: Robust Subgroup Multi-Signatures for Consensus.
Summary: This work points out that the traditional security model for multi- signatures is insufficient for consensus protocols, as it assumes that every party in the set participates in the multi-signature computation phase and is honest.
Authors: David Galindo*† and Jia Liu*,
2. Paper Title: On the Serverless Nature of Blockchains and Smart Contracts.
Summary: This work analyzes how the blockchain technology and smart contracts fit into the serverless picture and derives a set of scenarios in which they act as different component types in serverless architectures.
Affiliations: * University of Stuttgart.
3. Paper Title: General Purpose Atomic Crosschain Transactions.
Summary: This paper introduces and empirically examines a protocol that provides atomic, synchronous, inter-contract function calls across blockchains.
4. Paper Title: Verification of recursive Bitcoin contracts.
Summary: This work addresses the problem of verifying liquidity on BitML, a DSL for smart contracts with a secure compiler to Bitcoin, featuring primitives for currency transfers, contract renegotiation and consensual recursion.
1. Paper Title: Delegated RingCT: faster anonymous transactions.
Summary: A modification to RingCT protocol with stealth addresses that makes it compatible with Delegated Proof of Stake based consensus mechanisms called Delegated RingCT.
Affiliations: * University of Beira Interior.
Summary: A simple and efficient Plasma system leveraging the power of trusted execution environments (TEE).
Affiliations: * TU Darmstadt.
1. Paper Title: Malicious Security Comes for Free in Consensus with Leaders.
Summary: This work removes the so far quadratic bit communication cost of three desirable properties of consensus protocols with leaders: Responsiveness with Optimal latency, Optimistic Fast Track and Strong Unanimity.
Authors: Matthieu Rambaud*,
Affiliations: * Telecom Paris.
2. Paper Title: Close Latency–Security Trade-off for the Nakamoto Consensus.
Summary: This paper describes a continuous-time model for blockchains and develops a rigorous analysis that yields very close latency (or confirmation time) and security bounds.
Summary: This work investigates the relationship between underlying blockchain mechanism of cryptocurrencies and its distributional characteristics.
Conferences, Journals, & CFPs:
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