QUANTAS 2 An Abstract, Concrete and Byzantine Simulator

TL;DR

QUANTAS 2 is a versatile distributed algorithm simulator that supports abstract, concrete, and Byzantine fault simulations, enabling researchers to analyze various distributed systems efficiently.

Contribution

It extends the original QUANTAS by adding concrete execution and Byzantine fault modeling, facilitating comprehensive and flexible distributed algorithm testing.

Findings

Supported blockchain, consensus, DHT, and data link algorithms.

Performed extensive experiments including parasite-chain sweeps and fault injection.

Validated the platform's effectiveness across multiple distributed system scenarios.

Abstract

We present QUANTAS 2: a new distributed algorithm simulator and quantitative performance analysis tool. We use the original QUANTAS as a foundation. QUANTAS 2 can perform fast abstract exploration, concrete validation, and adversarial fault injection while preserving a compact implementation model for distributed algorithm researchers. The original QUANTAS was designed as an abstract, round-based simulator, which allows researchers to separate algorithmic behavior from the artifacts of a particular operating system, network stack, or physical deployment. QUANTAS 2 extends that design in two directions. First, QUANTAS 2 supports a concrete socket-based execution mode, allowing the same algorithm implementations and JSON experiment descriptions to run across local or distributed computers. Second, QUANTAS 2 adds a reusable Byzantine-fault interface in which Byzantine behavior is encoded as composable fault strategy that substitutes correct sends, receives, and local computation. This allows researchers to simulate crash, equivocation, selfish-mining, and other adversarial behaviors without rewriting the simulated algorithm. We demonstrate the resulting platform on blockchain, consensus, distributed hash table, and reliable data link algorithms. We perform parasite-chain sweeps for proof-of-work blockchains, PBFT equivocation experiments, Raft crash experiments, and Chord/Kademlia scale experiments over both abstract and concrete modes.