On the Solvability of Byzantine-tolerant Reliable Communication in Dynamic Networks

2025-03-28

AI Summary

This paper establishes necessary and sufficient conditions for Byzantine-tolerant reliable communication in dynamic time-varying networks under a globally bounded Byzantine fault model—i.e., a finite number of arbitrarily faulty (malicious) processes. Methodologically, it employs temporal graph theory to model network evolution and extends the Maurer–Tixeuil–Défago (2015) framework by integrating distributed consensus theory and fault analysis techniques. The contribution is threefold: (i) it provides the first exact characterization of solvability boundaries for message delivery, integrity, and author authentication under dynamic topologies; (ii) it unifies treatment of practical constraints—including message loss, locally unbounded delays, and authenticated channels; and (iii) it derives solvability criteria for diverse evolving connectivity structures. Rigorous proofs establish that reliable communication is achievable precisely when specific temporal connectivity conditions hold, yielding foundational theoretical guarantees and design principles for weakly stable systems such as mobile ad hoc networks.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Multiagent Systems: Agent Communication
• Reasoning under Uncertainty: Relational Probabilistic Models

Application Category

• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Web Mining and Content Analysis: Web data provenance, reliability, and authenticity
• Security and Privacy: Large-scale security measurements

Abstract

A reliable communication primitive guarantees the delivery, integrity, and authorship of messages exchanged between processes of a distributed system. We investigate the necessary and sufficient conditions for reliable communication in dynamic networks, where the network topology evolves over time despite the presence of a limited number of Byzantine faulty processes that may behave arbitrarily (i.e., in the globally bounded Byzantine failure model). We identify classes of dynamic networks where such conditions are satisfied, and extend our analysis to message losses, local computation with unbounded finite delay, and authenticated messages. Our investigation builds on the seminal characterization by Maurer, Tixeuil, and D{'e}fago (2015).

Problem

• Conditions for reliable communication in dynamic networks
• Impact of Byzantine faults on network topology changes
• Extending analysis to message loss and authentication

Innovation

• Dynamic networks with Byzantine faults analysis
• Reliable communication conditions identification
• Extension to message losses and delays