Requirement Model of School Management System for Adult Commercial Secondary School in Somalia (ACSSMS)

To develop a system, it is necessary for the system's analyst to provide a model. In order to produce this model, the analyst must identify the user’s requirement first. Requirement model is one of the techniques used to model out the user’s requirement for a specific system before the development of that system. In other words, requirement model gives a view of the user’s requirement for a particular system. The purpose of this study is to create a requirement model as a basis to develop school management system for Adult Commercial Secondary School in Somalia. So, during this study, the UML graphical notation was used to model out the requirement model of the proposed school management system, and the requirement model was designed and presented using different UML tools (e.g., use case diagram, use case specifications, activity diagram, sequence diagram, collaboration diagram and class diagram), and supporting textual information. Also, a small prototype was then developed and presented in this study, which covers some of the main functional requirements, so as to assist the school in managing their daily operations effectively and more efficiently. Thus, this study is believed to be a step forward and very crucial guidance for Adult School in Somalia to be able to give this model to system developers to build the proposed school management system

Generalising Projection in Asynchronous Multiparty Session Types

Multiparty session types (MSTs) provide an efficient methodology for specifying and verifying message passing software systems. In the theory of MSTs, a global type specifies the interaction among the roles at the global level. A local specification for each role is generated by projecting from the global type on to the message exchanges it participates in. Whenever a global type can be projected on to each role, the composition of the projections is deadlock free and has exactly the behaviours specified by the global type. The key to the usability of MSTs is the projection operation: a more expressive projection allows more systems to be type-checked but requires a more difficult soundness argument. In this paper, we generalise the standard projection operation in MSTs. This allows us to model and type-check many design patterns in distributed systems, such as load balancing, that are rejected by the standard projection. The key to the new projection is an analysis that tracks causality between messages. Our soundness proof uses novel graph-theoretic techniques from the theory of message-sequence charts. We demonstrate the efficacy of the new projection operation by showing many global types for common patterns that can be projected under our projection but not under the standard projection operation

Modelling Smart Card Security Protocols in SystemC TLM

Smart cards are an example of advanced chip technology. They allow information transfer between the card holder and the system over secure networks, but they contain sensitive data related to both the card holder and the system, that has to be kept private and confidential. The objective of this work is to create an executable model of a smart card system, including the security protocols and transactions, and to examine the strengths and determine the weaknesses by running tests on the model. The security objectives have to be considered during the early stages of systems development and design, an executable model will give the designer the advantage of exploring the vulnerabilities early, and therefore enhancing the system security. The Unified Modeling Language (UML) 2.0 is used to model the smart card security protocol. The executable model is programmed in SystemC with the Transaction Level Modeling (TLM) extensions. The final model was used to examine the effectiveness of a number of authentication mechanisms with different probabilities of failure. In addition, a number of probable attacks on the current security protocol were modeled to examine the vulnerabilities. The executable model shows that the smart card system security protocols and transactions need further improvement to withstand different types of security attacks

Modelling Smart Card Security Protocols in SystemC TLM

Smart cards are an example of advanced chip technology. They allow information transfer between the card holder and the system over secure networks, but they contain sensitive data related to both the card holder and the system, that has to be kept private and confidential. The objective of this work is to create an executable model of a smart card system, including the security protocols and transactions, and to examine the strengths and determine the weaknesses by running tests on the model. The security objectives have to be considered during the early stages of systems development and design, an executable model will give the designer the advantage of exploring the vulnerabilities early, and therefore enhancing the system security. The Unified Modeling Language (UML) 2.0 is used to model the smart card security protocol. The executable model is programmed in SystemC with the Transaction Level Modeling (TLM) extensions. The final model was used to examine the effectiveness of a number of authentication mechanisms with different probabilities of failure. In addition, a number of probable attacks on the current security protocol were modeled to examine the vulnerabilities. The executable model shows that the smart card system security protocols and transactions need further improvement to withstand different types of security attacks

SpecSatisfiabilityTool: A tool for testing the satisfiability of specifications on XML documents

We present a prototype that implements a set of logical rules to prove the satisfiability for a class of specifications on XML documents. Specifications are given by means of constrains built on Boolean XPath patterns. The main goal of this tool is to test whether a given specification is satisfiable or not, and justify the decision showing the execution history. It can also be used to test whether a given document is a model of a given specification and, as a by-product, it permits to look for all the relations (monomorphisms) between two patterns and to combine patterns in different ways. The results of these operations are visually shown and therefore the tool makes these operations more understandable. The implementation of the algorithm has been written in Prolog but the prototype has a Java interface for an easy and friendly use. In this paper we show how to use this interface in order to test all the desired properties.Comment: In Proceedings PROLE 2014, arXiv:1501.0169

Automated reasoning for attributed graph properties

Graphs are ubiquitous in computer science. Moreover, in various application fields, graphs are equipped with attributes to express additional information such as names of entities or weights of relationships. Due to the pervasiveness of attributed graphs, it is highly important to have the means to express properties on attributed graphs to strengthen modeling capabilities and to enable analysis. Firstly, we introduce a new logic of attributed graph properties, where the graph part and attribution part are neatly separated. The graph part is equivalent to first-order logic on graphs as introduced by Courcelle. It employs graph morphisms to allow the specification of complex graph patterns. The attribution part is added to this graph part by reverting to the symbolic approach to graph attribution, where attributes are represented symbolically by variables whose possible values are specified by a set of constraints making use of algebraic specifications. Secondly, we extend our refutationally complete tableau-based reasoning method as well as our symbolic model generation approach for graph properties to attributed graph properties. Due to the new logic mentioned above, neatly separating the graph and attribution parts, and the categorical constructions employed only on a more abstract level, we can leave the graph part of the algorithms seemingly unchanged. For the integration of the attribution part into the algorithms, we use an oracle, allowing for flexible adoption of different available SMT solvers in the actual implementation. Finally, our automated reasoning approach for attributed graph properties is implemented in the tool AutoGraph integrating in particular the SMT solver Z3 for the attribute part of the properties. We motivate and illustrate our work with a particular application scenario on graph database query validation.Peer ReviewedPostprint (author's final draft