‹Programming› 2023
Mon 13 - Fri 17 March 2023 Tokyo, Japan

In programming, protocols are everywhere. Protocols describe the pattern of interaction (or communication) between software systems, for example, between a user-space program and the kernel or between a local application and an online service. Ensuring conformance to protocols avoids a significant class of software errors. Subsequently, there has been a lot of work on verifying code against formal protocol specifications. The pervading approaches focus on distributed settings involving parallel composition of processes within a single monolithic protocol description. However we observe that, at the level of a single thread/process, modern software must often implement a number of clearly delineated protocols at the same time which become dependent on each other, e.g., a banking API and one or more authentication protocols. Rather than plugging together modular protocol-following components, the code must re-integrate multiple protocols into a single component.

We address this concern of combining protocols via a novel notion of ‘interleaving’ composition for protocols described via a process algebra. User-specified, domain-specific constraints can be inserted into the individual protocols to serve as ‘contact points’ to guide this composition procedure, which outputs a single combined protocol that can be programmed against. Our approach allows an engineer to then program against a number of protocols that have been composed (re-integrated), reflecting the true nature of applications that must handle multiple protocols at once.

We prove various desirable properties of the composition, including behaviour preservation: that the composed protocol implements the behaviour of both component protocols. We demonstrate our approach in the practical setting of Erlang, with a tool implementing protocol composition that both generates Erlang code from a protocol and generates a protocol from Erlang code. This tool shows that, for a range of sample protocols (including real-world examples), a modest set of constraints can be inserted to produce a small number of candidate compositions to choose from.

As we increasingly build software interacting with many programs and subsystems, this new perspective gives a foundation for improving software quality via protocol conformance in a multi-protocol setting.

Wed 15 Mar

Displayed time zone: Osaka, Sapporo, Tokyo change

14:00 - 15:30
Research Papers 2Research Papers at Faculty of Engineering Building 2, Room 212
Chair(s): Sebastian Kloibhofer Johannes Kepler University Linz
14:00
30m
Talk
Continuation-Passing Style, Defunctionalization, Accumulations, and AssociativityVol. 6
Research Papers
Jeremy Gibbons Department of Computer Science, University of Oxford
Link to publication
14:30
30m
Talk
Consistency types for replicated data in a higher-order distributed programming languageVol. 5
Research Papers
Xin Zhao KTH Royal Institute of Technology, Philipp Haller KTH Royal Institute of Technology
Link to publication
15:00
30m
Talk
A Theory of Composing ProtocolsVol. 7
Research Papers
Laura Bocchi University of Kent, Dominic Orchard University of Kent, UK, A. Laura Voinea University of Kent, UK
Link to publication