Abstract In contrast to traditional business models, digital business ecosystems (DBEs) have several distinctive features—heterogeneity of involved actors, symbiosis in the exchange of resources, co-evolution of their interactions, and self-organisation. Designing DBEs is a task demanding a well-defined DBE’s scope, roles and responsibilities of the actors, their interactions and dependencies, as well as versatile technologies and data. The study focuses on two DBEs—Marispace-X and Skippo in the maritime domain to capture the tenets of the blue economy with dataspaces. Because the design approaches to DBE are scarce due to the paradigm’s novelty, the study aims to evaluate a model-based design method, DBEmap. The evaluation results concerning practitioners’ perceived usefulness of the DBEmap and its support for integrating DBE-related perspectives and benchmarking DBE resilience are presented. Reflections on the applicability of DBEmap and its implications for organisational support, highlighting the systematic guidance and actionable outcomes observed in the two case workshops, are discussed alongside the study’s limitations and directions for future research.

A Mix Net is a cryptographic protocol that unlinks the correspondence between its inputs and its outputs. In this paper, we formally analyse a Mix Net using the process algebra CSP and its associated model checker FDR. The protocol that we verify removes the reliance on a Web Bulletin Board: rather than communicating via a Web Bulletin Board, the protocol allows the mix servers to communicate directly, exchanging signed messages and maintaining their own records of the messages they have received. Mix Net analyses in the literature are invariably focused on safety properties; important liveness properties, such as deadlock freedom, are wholly neglected. This is an unhappy omission, however, since a Mix Net that produces no results is of little use. In contrast, we verify here that the Mix Net is guaranteed to terminate, with each honest mix server outputting the decrypted vector of plaintexts alongside a chain proving that each re-encryption/permutation and partial decryption operation was performed correctly, under the assumption that there is an honest majority of them acting according to the protocol.

Software artifacts are subject tomany sources of evolutionary pressure, which range from technical changes due to rapidly evolving technology platforms, to modifications caused by new requirements and insights emerging from the business domain. These modifications include changes at all levels, from requirements through architecture and design, to source code, documentation and test suites, and might affect any kinds of models. Therefore, adopting models, techniques, and tools for coping with and managing changes that accompany the evolution of software models is an essential discipline of Software Engineering.

Services offer the possibility to describe the functionality of a system exceeding the limited modularization supplied by component-based approaches. For that reason, service-based systems engineering has traditionally proven useful in the development of telecommunication systems, by separating individual services – or features – with high degree of interaction between the components of the system and describing the complete behavior of the system when combined. Due to their modular character, services are especially suited for the development of configurable or extendable systems, supporting product lines as well as incremental development. Thus, beyond telecommunication, especially the notion of web services has received a lot of interest as a means for publishing and accessing software functions via web standards to yield flexibly configurable systems. For similar reasons, increasingly the notion of a service is also gaining ground in other application domains, such as spontaneous networks, ubiquitous computing, and even safety critical systems from the automotive or avionics domain. Precise specification and correct implementation of requirements for services are essential in most of these application domains. Many notions of service refer only to syntactic interfaces. Typical examples include the service notions inherent in WSDL/SOAP and technologies such as .NET/J2EE building on these service notions. This is inadequate for more elaborate service specifications that include, for instance, quality-of-service properties. In many approaches, services are not treated as first-class modeling elements, say, in UML/UML-RT and SDL. Therefore, especially in the application domains mentioned above, a suitable notion of service is needed to support service-based software engi-