this page is a dynamically changing index of all our posts, it’s one more place to start reading Decentralized Thoughts

Basics, Foundations, and Classics

Start with the definition of Consensus and Agreement. Then learn about the network model, the threshold adversary model, and the power of the adversary. Finally, many protocols need a trusted setup phase.

You can learn more about Partial Synchrony and about different relaxations of Broadcast.

One of the classic protocols of distributed computing is the Dolev-Strong Authenticated Broadcast protocol.

State Machine Replication

We begin by defining State Machine Replication (SMR) and talk about different degrees of SMR fault tolerance. The scalability and performance of a State Machine Replication system is not just about Consensus, but also about Data and Execution.

We start with a simple SMR for crash failures. We later extend this to omission failures. First via single shot.

Lower Bounds

• Consensus with Ommsion failures requires $f<n/2$.

• Byzantine Consensus in Partial Synchrony requires $f<n/3$.

• Byzantine Consensus with no PKI (or more generally when the adversary can simulate) requires $f<n/3$.

• Consensus often needs a quadratic number of messages.

• Consensus is challenging because some initial state must be uncommitted and this imples executions with at least $f+1$ rounds in Synchrony and non-terminating executions in Asynchrony (the FLP impossibility).

Blockchains

• The first blockchain (or how to timestamp a digital document).

• Setup assumptions in Bitcoin and Ethereum and the notion of checkpointing a blockchain.

• Security analysis of Nakamoto Consensus

• Blockchain Selfish Mining.

• Payment Channels

Cryptography

The basics:

• Cryptographic hash function

• Polynomials over a finite field

• Polinomial secret sharing.

More advanced:

• Bilinear Accumulators and range proofs.

• Private set intersection: part 1 and part 2

Research

• What is the difference between PBFT, Tendermint, SBFT, and HotStuff ?

• Survay of modern Authenticated Synchronous BFT protocols

• Sync HotStuff

• Streamlet

• Optimal Optimistic Responsivness

• Encrypted Blockchain Databases part 1 and part 2.

• Asynchronous Fault-Tolerant Computation with Optimal Resilience

• Resolving the Availability-Finality Dilemma

• BFT Protocol Forensics