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Software that is used to control machines and robots must be predictable and reliable. Model-Driven Design (MDD) techniques are used to comply with both the technical and business needs. This paper introduces a CSP meta-model that is suitable for these MDD techniques. The meta-model describes the structure of CSP models that are designed; using this meta-model it is possible to use all regular CSP constructs when constructing a CSP model. The paper also presents a new tool suite, called TERRA, based on Eclipse and its frameworks. TERRA contains a graphical CSP model editor (using the new CSP meta-model), model validation tools and code generation tools. The model validation tools check whether the model conforms to the meta-model definition as well as to additional rules. Models without any validation problems result in proper code generation, otherwise the developer needs to address the found problems to be sure code generation will succeed. The code generation tools are able to generate CSPm code that is readable by FDR and to generate C++/LUNA code that is executable on embedded targets. The meta-model and the TERRA tool suite are tested by designing CSP models for several of our laboratory setups. The generated C++/LUNA code for the laboratory setups is able to control them as expected. Additionally, the paper contains an example model containing all supported CSP constructs to show the CSPm code generation results. So it can be concluded that the meta-model and TERRA are usable for these kind of tasks.

The aims of this workshop are to develop a range of interesting practical demonstrators showing the benefits and advantages to systems engineering of Com- municating Process Architectures (CPA). Examples range from essential, basic cases towards the challenging ones. Also, benchmark cases – or cases that are used so often that they grow towards a benchmark, like the commstime example – will be developed.

Many security protocols are built as the composition of an application-layer protocol and a secure transport protocol, such as TLS. There are many approaches to proving the correctness of such protocols. One popular approach is verification by abstraction, in which the correctness of the application-layer protocol is proven under the assumption that the transport layer satisfies certain properties, such as confidentiality. Following this approach, we adapt the strand spaces model in order to analyse application-layer protocols that depend on an underlying secure transport layer, including unilaterally authenticating secure transport protocols, such as unilateral TLS. Further, we develop proof rules that enable us to prove the correctness of application-layer protocols that use either unilateral or bilateral secure transport protocols. We then illustrate these rules by proving the correctness of WebAuth, a single-sign-on protocol that makes extensive use of unilateral TLS. In this thesis we also present a full proof of the model's soundness. In particular, we prove that, subject to a suitable independence assumption, if there is an attack against the application-layer protocol when layered on top of a particular secure transport protocol, then there is an attack against the abstracted model of the application-layer protocol. In contrast to existing work in this area, the independence assumption consists of eight statically-checkable conditions, meaning that it can be checked statically, rather than having to consider all possible runs of the protocol. Lastly, we extend the model to allow protocols that consist of an arbitrary number of layers to be proven correct. In this case, we prove the correctness of the intermediate layers using the high-level strand spaces model, by abstracting away from the underlying transport-layers. Further, we extend the above soundness results in order to prove that the multi-layer approach is sound. We illustrate the effectiveness of our technique by proving the correctness of a couple of simple multi-layer protocols.

There are many approaches to proving the correctness of application-layer protocols that are layered on secure transport protocols, such as TLS. One popular approach is verification by abstraction, in which the correctness of the application-layer protocol is proven under the assumption that the transport layer satisfies certain properties. Following this approach, we adapt the strand spaces model in order to analyse application-layer protocols that depend on unilaterally authenticating secure transport protocols, such as unilateral TLS. We develop proof rules that enable us to prove the correctness of application-layer protocols that use either unilateral or bilateral secure transport protocols, and illustrate them by proving the correctness of WebAuth, a single-sign-on protocol that makes extensive use of unilateral TLS. © 2012 Springer-Verlag.