Formal modular reasoning for cryptography-dependent distributed systems

Develop a formal and modular reasoning framework for distributed systems that rely on cryptographic primitives beyond the simple assumptions modeled in Sync, enabling such systems to be expressed and verified (e.g., by extending the Sync denotational semantics and Async operational semantics to incorporate cryptographic operations and their guarantees).

Background

In the design of Sync, the authors deliberately restrict the language to exclude branches/loops and cryptographic primitives. As a result, distributed systems that depend on sophisticated cryptographic mechanisms cannot currently be expressed or reasoned about within their framework.

They explicitly note that handling cryptography is a separate challenge and leave support for specific primitives to future work. This establishes a clear gap: while the twin languages Sync/Async provide a path for compositional functional reasoning about asynchrony and faults, they do not yet address protocols whose correctness critically depends on cryptographic operations.