A Formal Service Specification for the Internet Open Trading Protocol

Abstract

This paper presents our service specification for the Internet Open Trading Protocol (IOTP) developed using Coloured Petri Nets. To handle IOTP's complexity, we apply a protocol engineering methodology based on Open Systems Interconnection (OSI) principles consisting of five iterative steps: the definition of service primitives and parameters; the creation of an automaton specifying the local service language for each of the four trading roles of IOTP; the development of a CPN model synthesizing the local automata into a specification of the global service capturing the correlations between the service primitives at the distributed trading roles; the generation of the occurrence graph representing the global service language; and lastly a new step, language comparison to ensure the consistency between the specifications of the local service language and the global service language. The outcome is a proposed formal service specification for IOTP. Keywords: System verification using nets, Case studies, Higher-level net models, Internet protocols, E-commerce.