Chronolock: Causal Time-Ordering with Blockchain Smart Contracts

Abstract

Distributed systems struggle with synchronization, especially when components must agree on the order of events across application or trust boundaries. Without clear causal ordering, systems can become vulnerable to inconsistencies, coordination failures, and auditability issues.

This thesis presents \textbf{Chronolock}, a blockchain-hybrid system that enforces causal-time ordering across distributed components. Chronolock combines on-chain dependency verification through a blockchain smart contract with a developer-focused SDK that abstracts away blockchain complexity. Messages are published with explicit dependencies, which must be verified on-chain before the message is accepted, ensuring a tamper-proof and verifiable event sequence.

Chronolock is designed as a proof-of-concept that prioritizes ordering integrity over raw throughput. Through controlled experiments, we evaluate its performance and limitations, including throughput constraints and deployment complexity. While not suited for high-throughput applications, Chronolock is a viable coordination mechanism for scenarios where traceability, causality, and correctness are more important than speed or flexibility.

Distributed systems struggle with synchronization, especially when components must agree on the order of events across application or trust boundaries. Without clear causal ordering, systems can become vulnerable to inconsistencies, coordination failures, and auditability issues.

This thesis presents \textbf{Chronolock}, a blockchain-hybrid system that enforces causal-time ordering across distributed components. Chronolock combines on-chain dependency verification through a blockchain smart contract with a developer-focused SDK that abstracts away blockchain complexity. Messages are published with explicit dependencies, which must be verified on-chain before the message is accepted, ensuring a tamper-proof and verifiable event sequence.

Chronolock is designed as a proof-of-concept that prioritizes ordering integrity over raw throughput. Through controlled experiments, we evaluate its performance and limitations, including throughput constraints and deployment complexity. While not suited for high-throughput applications, Chronolock is a viable coordination mechanism for scenarios where traceability, causality, and correctness are more important than speed or flexibility.