This Week in Blockchain Research Issue #55

Issue #55

Issue #55

Paper of the Week:

Paper Title: Twins: White-Glove Approach for BFT Testing.


  1. Byzantine behavior is unconstrained, hence, one can only implement a subset of such behaviors and the subset of Byzantine behaviors to be tested are chosen by system de- velopers, who are naturally tainted by having designed the system with certain limited Byzantine behaviors in mind.

  2. In addition, similar challenges arise when testing BFT protocols via formal specification and verification methods. Branching over Byzantine (arbitrary) behavior is unconstrained, leading to state explosion when modeling and model checking.

  3. Moreover, as a pragmatical consideration, developing test code that implements Byzantine attacks might be risky.

  4. This work proposes a new approach for systematically testing BFT systems. Instead of coding incorrect behavior, the proposed work runs faulty nodes in two (or generally, k) parallel universes in tandem. Both instances have the same credentials/signing-keys and run autonomously.

  5. The proposed work is based on the insight that most interesting Byzantine attacks can rely on a correct implementation of the protocol, such that a Byzantine node appears to be honest. Therefore, a message not generated by the correct implementation will not be generated. 

  6. Several famous attacks on BFT protocols are reinstated in this approach. In two of these attacks, it took the community more than a decade to discover protocol flaws that this work would have surfaced within minutes.

  7. The authors refer to their proposed work as a “white glove” approach: It is neither “block-box”, since it does modify the internal behavior of the tested system, nor is it “white-box”, because it does not open internal code modules.

  8. It minutely interacts with existing code to control message delivery and schedule various coarse-steps such as protocol rounds. Most importantly, it is practical to deploy in real systems as it uses existing correct node code. In fact, it can be implemented by thinly wrapping twin nodes with a network-scheduler acting as an adversary, easily keeping up with an evolving software project.

AuthorsShehar Bano*, Alberto Sonnino*, Andrey Chursin*, Dmitri Perelman*, Dahlia Malkhi*,

Affiliations: * Calibra.


1. Paper Title: Threshold ECDSA for Decentralized Asset Custody.

Summary: A new threshold ECDSA protocol that is designed with interoperability applications in mind and achieves several improvements over previous solutions.

Authors: Adam Gągol* and Damian Straszak*,

Affiliations* Cardinals.

2. Paper Title: Storing and Retrieving Secrets on a Blockchain.

Summary: This work uses a blockchain to achieve a functionality that is essentially equivalent to extractable witness encryption.

Authors: Vipul Goyal*, Abhiram Kothapalli*, Elisaweta Masserova*, Bryan Parno*, and Yifan Song*,

Affiliations* Carnegie Mellon University.


1. Paper Title: SEPAR: A Privacy-Preserving Blockchain-based System for Regulating Multi-Platform Crowdworking Environments.

Summary: A technical solution to the problem of imposing global constraints on distributed independent entities in the context of multi-platform crowdworking systems.

Authors: Mohammad Javad Amiri*, Joris Duguépéroux†, Tristan Allard†, Divyakant Agrawal*, and Amr El Abbadi*,

Affiliations* University of California Santa Barbara and † Univ Rennes.


1. Paper Title: JaxNet: Scalable Blockchain Network.

Summary: A scalable, decentralized cryptocurrency that is based on Proof of Work.

Authors: Iurii Shyshatsky*, Vinod Manoharan*, Taras Emelyanenko *, and Lucas Leger*,

Affiliations* JaxNet.


1. Paper Title: Proof-Carrying Data from Accumulation Schemes.

Summary: An accumulation scheme for a non-interactive argument, showing that this suffices to construct proof-carrying data (PCD), even if the argument itself does not have a sublinear-time verifier.

Authors: Benedikt Bünz*, Alessandro Chiesa†, Pratyush Mishra†, and Nicholas Spooner†,

Affiliations* Stanford University and † UC Berkeley.

2. Paper Title: Aggregatable Subvector Commitments for Stateless Cryptocurrencies.

Summary: This work formalizes aggregatable subvector commitment  (aSVCs), gives an efficient construction in prime-order groups from constant-sized polynomial commitments, and uses it to bootstrap a highly-efficient stateless cryptocurrency.

Authors: Alin Tomescu*, Ittai Abraham*, Vitalik Buterin†, Justin Drake†, Dankrad Feist†, and Dmitry Khovratovich†,

Affiliations* VMware Research and † Ethereum Foundation.


1. Paper Title: Account Management in Proof of Stake Ledgers.

Summary: A formal PoS wallet construction that enables delegation and stake pool formation.

Authors: Dimitris Karakostas*† and Aggelos Kiayias*† and Mario Larangeira†‡

Affiliations* University of Edinburgh, † IOHK, and ‡ Tokyo Institute of Technology.

2. Paper Title: From Byzantine Replication to Blockchain: Consensus is only the Beginning.

Summary: This paper discussed some misalignments between the state machine replication approach and the permissioned blockchain requirements and proposed several techniques to address them.

Authors: Alysson Bessani‡*, Eduardo Alchieri†, Joao Sousa*‡, Andre Oliveira‡*, Fernando Pedone‡,

Affiliations* Universidade de Lisboa, † Universidade de Brasılia, and Universita della Svizzera Italiana


1. Paper Title: Applying Blockchain Layer2 Technology to Mass E-Commerce.

Summary: The effect that layer2 technology can provide in reducing fee costs and improving transaction volumes.

AuthorsSijia Zhao* and Donal O’Mahony*,

Affiliations: * Trinity College Dublin.

2. Paper Title: Examining the National Security Implications of Cryptocurrencies.

Summary: This article argues that the United States government should embrace cryptocurrencies that are pseudonymous and should further study those which are considered anonymous.

Authors: Raffi Teperdjian*,

Affiliations* George Washington University.

Conferences & CFPs:

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