Use of B method for dynamic structures in S2OPC

The software B method has so far been mainly used in the industrial world to develop safety critical software with very basic memory management limited to arrays of fixed size defined at compilation time.

We present here an alternative approach for modelling software based on a more classic memory management with dynamically allocated complex data structures accessed through pointers.

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An overview of the GPR technology

GPR diagram

Implementing the various components of a software project can be a tedious task. This is why, for many years, a set of tools has been developed to facilitate, secure and systematize it.

This article is an introduction to one of the existing solutions named GNAT GPR (Gnat PRoject).

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Certificate trust chain validation in OPC UA


OPC UA client/server protocol security is based on application certificates, each application shall trust each other. Determining if a certificate is trusted might include verification of a trust chain in cases that were not expected at first sight. This article explains how to validate a certificate to pass OPC UA certification 1 and hence how to configure correctly certificate validation to ensure your application certificate is accepted.

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Porting an Ada legacy software

Ada Lovelace

Porting an Ada legacy software can be a delicate task despite the intrinsic qualities of the Ada language such as, for example, its true portability. This article identifies the main problems that may be encountered and how they can best be addressed.

This article is about the Ada language but, in terms of approach, some points are transposable to other languages.

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