Year: 2025
Type: article
Abstract: Session types provide a typing discipline for message-passing systems. However, their theory often assumes an ideal world: one in which everything is reliable and without failures. Yet this is in stark contrast with distributed systems in the real world. To address this limitation, we introduce a new asynchronous multiparty session types (MPST) theory with crash-stop failures, where processes may crash arbitrarily and cease to interact after crashing. We augment asynchronous MPST and processes with crash handling branches, and integrate crash-stop failure semantics into types and processes. Our approach requires no user-level syntax extensions for global types, and features a formalisation of global semantics, which captures complex behaviours induced by crashed/crash handling processes. Our new theory covers the entire spectrum, ranging from the ideal world of total reliability to entirely unreliable scenarios where any process may crash, using optional reliability assumptions. Under these assumptions, we demonstrate the sound and complete correspondence between global and local type semantics, which guarantee deadlock-freedom, protocol conformance, and liveness of well-typed processes by construction, even in the presence of crashes. Comment: arXiv admin note: substantial text overlap with arXiv:2305.06238
Institutions: University of St Andrews, University of Oxford
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: diamond
Awards: From Data Types to Session Types---A Basis for Concurrency and Distribution, Turtles: Protocol-Based Foundations for Distributed Multiagent Systems, Session Types for Reliable Distributed Systems (STARDUST), Conversation-Based Governance for Distributed Systems by Multiparty Session Types, Morello-HAT: Morello High-Level API and Tooling, Border Patrol: Improving Smart Device Security through Type-Aware Systems Design, Exploiting Parallelism through Type Transformations for Hybrid Manycore Systems, Verified Simulation for Large Quantum Systems (VSL-Q), AppControl: Enforcing Application Behaviour through Type-Based Constraints, POST: Protocols, Observabilities and Session Types
OpenAlex ID: W4409564932