Choreographies and Cost Semantics for Reliable Communicating Systems

Communicating systems have become ubiquitous in today\u27s society.Unfortunately, the complexity of their interactions makesthem particularly prone to failures such as deadlocked statescaused by misbehaving components, or memory exhaustion due to a surgein message traffic (malicious or not).These vulnerabilities constitute a real risk to users, withconsequences ranging from minor inconveniences to the possibility ofloss of life and capital.This thesis presents results that aim to increase the reliability of communicating systems.First, we implement a choreography language that can, by construction, only describe deadlock-free systems.Second, we develop a cost semantics to prove programs free of out-of-memory errors.Lastly, we improve both results by using novel semantic approaches that strengthen key theorems and facilitate further proof development.All of these results are formalized in the HOL4 theorem prover and integrated with the CakeML verified stack

Choreographies and Cost Semantics for Reliable Communicating Systems

Communicating systems have become ubiquitous in today\u27s society.Unfortunately, the complexity of their interactions makes themparticularly prone to failures such as deadlocked states causedby misbehaving components, or memory exhaustion due to a surge inmessage traffic (malicious or not). These vulnerabilitiesconstitute a real risk to users, with consequences ranging fromminor inconveniences to the possibility of loss of life andcapital. This thesis presents two results that aim to increasethe reliability of communicating systems. First, we implement achoreography language which by construction can only describesystems that are deadlock-free. Second, we develop a costsemantics to prove programs free of out-of-memory errors. Both ofthese results are formalized in the HOL4 theorem prover andintegrated with the CakeML verified stack