Be Prepared When Network Goes Bad: An Asynchronous View-Change Protocol

The popularity of permissioned blockchain systems demands BFT SMR protocols that are efficient under good network conditions (synchrony) and robust under bad network conditions (asynchrony). The state-of-the-art partially synchronous BFT SMR protocols provide optimal linear communication cost per decision under synchrony and good leaders, but lose liveness under asynchrony. On the other hand, the state-of-the-art asynchronous BFT SMR protocols are live even under asynchrony, but always pay quadratic cost even under synchrony. In this paper, we propose a BFT SMR protocol that achieves the best of both worlds -- optimal linear cost per decision under good networks and leaders, optimal quadratic cost per decision under bad networks, and remains always live.

[1]  Jing Xu,et al.  Dumbo: Faster Asynchronous BFT Protocols , 2020, IACR Cryptol. ePrint Arch..

[2]  Nancy A. Lynch,et al.  Impossibility of distributed consensus with one faulty process , 1985, JACM.

[3]  Elaine Shi,et al.  PiLi: An Extremely Simple Synchronous Blockchain , 2018, IACR Cryptol. ePrint Arch..

[4]  Ittai Abraham,et al.  Revisiting Fast Practical Byzantine Fault Tolerance: Thelma, Velma, and Zelma , 2018, ArXiv.

[5]  Victor Shoup,et al.  Optimistic Asynchronous Atomic Broadcast , 2005, ICALP.

[6]  Kartik Nayak,et al.  Sync HotStuff: Simple and Practical Synchronous State Machine Replication , 2020, 2020 IEEE Symposium on Security and Privacy (SP).

[7]  Qiang Tang,et al.  Bolt-Dumbo Transformer: Asynchronous Consensus As Fast As the Pipelined BFT , 2021, CCS.

[8]  Jonathan Katz,et al.  Network-Agnostic State Machine Replication , 2020, IACR Cryptol. ePrint Arch..

[9]  Alexander Spiegelman,et al.  In Search for a Linear Byzantine Agreement , 2020, ArXiv.

[10]  Ittai Abraham,et al.  HotStuff: BFT Consensus with Linearity and Responsiveness , 2019, PODC.

[11]  Michael K. Reiter,et al.  Fault-scalable Byzantine fault-tolerant services , 2005, SOSP '05.

[12]  Tal Moran,et al.  Combining Asynchronous and Synchronous Byzantine Agreement: The Best of Both Worlds , 2018, IACR Cryptol. ePrint Arch..

[13]  Klaus Kursawe,et al.  Optimistic Byzantine agreement , 2002, 21st IEEE Symposium on Reliable Distributed Systems, 2002. Proceedings..

[14]  Miguel Oom Temudo de Castro,et al.  Practical Byzantine fault tolerance , 1999, OSDI '99.

[15]  Elaine Shi,et al.  Thunderella: Blockchains with Optimistic Instant Confirmation , 2018, IACR Cryptol. ePrint Arch..

[16]  Vitalik Buterin,et al.  Casper the Friendly Finality Gadget , 2017, ArXiv.

[17]  Chen Feng,et al.  Fast-HotStuff: A Fast and Resilient HotStuff Protocol , 2020, ArXiv.

[18]  Dominic Williams,et al.  DFINITY Technology Overview Series, Consensus System , 2018, ArXiv.

[19]  Kartik Nayak,et al.  Flexible Byzantine Fault Tolerance , 2019, CCS.

[20]  Kartik Nayak,et al.  Communication complexity of byzantine agreement, revisited , 2018, Distributed Computing.

[21]  Kartik Nayak,et al.  On the Optimality of Optimistic Responsiveness , 2020, IACR Cryptol. ePrint Arch..

[22]  Jonathan Katz,et al.  Synchronous Consensus with Optimal Asynchronous Fallback Guarantees , 2019, IACR Cryptol. ePrint Arch..

[23]  Elaine Shi,et al.  The Honey Badger of BFT Protocols , 2016, CCS.

[24]  Guiling Wang,et al.  Dumbo-MVBA: Optimal Multi-Valued Validated Asynchronous Byzantine Agreement, Revisited , 2020, IACR Cryptol. ePrint Arch..

[25]  Ramakrishna Kotla,et al.  Zyzzyva , 2007, SOSP.

[26]  Jason Paul Cruz,et al.  Hybrid-BFT: Optimistically Responsive Synchronous Consensus with Optimal Latency or Resilience , 2020, IACR Cryptol. ePrint Arch..

[27]  Ethan Buchman,et al.  Tendermint: Byzantine Fault Tolerance in the Age of Blockchains , 2016 .

[28]  Marko Vukolic,et al.  The next 700 BFT protocols , 2010, EuroSys '10.

[29]  Alexander Spiegelman,et al.  ACE: Abstract Consensus Encapsulation for Liveness Boosting of State Machine Replication , 2019, OPODIS.

[30]  Dahlia Malkhi,et al.  Asynchronous Distributed Key Generation for Computationally-Secure Randomness, Consensus, and Threshold Signatures. , 2020, CCS.

[31]  Victor Shoup,et al.  Secure and Efficient Asynchronous Broadcast Protocols , 2001, CRYPTO.

[32]  Benny Pinkas,et al.  SBFT: A Scalable and Decentralized Trust Infrastructure , 2018, 2019 49th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN).

[33]  Nancy A. Lynch,et al.  Consensus in the presence of partial synchrony , 1988, JACM.

[34]  Damian Lesniak,et al.  Aleph: Efficient Atomic Broadcast in Asynchronous Networks with Byzantine Nodes , 2019, AFT.

[35]  Ittai Abraham,et al.  Asymptotically Optimal Validated Asynchronous Byzantine Agreement , 2019, PODC.