11 research outputs found
Analysis and representation of test cases generated from LOTOS
Cataloged from PDF version of article.This paper presents a method to generate, analyse and represent test cases from protocol specification. The language of temporal ordering specification (LOTOS) is mapped into an extended finite state machine (EFSM). Test cases are generated from EFSM. The generated test cases are modelled as a dependence graph. Predicate slices are used to identify infeasible test cases that must be eliminated. Redundant assignments and predicates in all the feasible test cases are removed by reducing the test case dependence graph. The reduced test case dependence graph is adapted for a local single-layer (LS) architecture. The reduced test cases for the LS architecture are enhanced to represent the tester's behaviour. The dynamic behaviour of the test cases is represented in the form of control graphs by inverting the events, assigning verdicts to the events in the enhanced dependence graph. © 1995
Slicing approach to specification for testability in LOTOS
Ankara : Department of Computer Engineering and Information Science and Institute of Engineering and Science, Bilkent Univ., 1993.Thesis (Master's) -- Bilkent University, 1993.Includes bibliographical references leaves 119-123With the recent increase in the use of formal methods in specification of
communication protocols, there is a need to base the conformance testing of
protocol implementations on formal specifications. This brings in the problem
of finding out special design issues to be used in the specification of such
systems that facilitate test generation. This aspect is called Specification For
Testability, and it is investigated in this study for the particular formal description
technique LOTOS. Specification for testability is approached from
the perspective of designing formal base protocol specifications, and then deriving
functional specifications from base specifications in order to use in test
generation. The method utilized for the derivation of functional specifications
is Ccdled slicing. As inspired from previous work in software engineering,
slices of protocol specifications are obtained systematically according to the
hierarchically designed test suite structures, where each slice corresponds to a
particular tunction of the protocol, and subsequent test generation is based on
the obtained slices. The techni(|ues developed are demonstrated on the simple
state-oriented specifications of INRES and ACSE protocols along with a
real base specification of the OSI Transport Protocol written in the constraintoriented
specification style. The results indicate that tests derived from functional
specifications have some remarkable properties with respect to test case
analysis and representation.AteĆ, Ahmet FeyziM.S
On the design of application protocols
In the last decades, much effort has been spent on the design and provision of sophisticated communication infrastructures. The development of end-user oriented distributed system applications, leaning on top of these communication infrastructures, so far has attracted little attention. This is regrettable, since communication infrastructures can only become useful and profitable if they can be deployed in the context of a sufficient number of distributed applications.\ud
Two important factors determine the success of distributed applications: (1) the provision of high quality application services and protocols at short time scales; and (2) the availability of standards for these services and protocols that can be used for the construction of ïżœopenïżœ distributed systems. The achievement of both (1) and (2) can be supported by a suitable design methodology.\ud
A design methodology entails a systematic approach to carry out complex designs, and therefore should incorporate proper concepts that enable the effective structuring of such designs. Concepts currently used for the design and structuring of application protocols appear to be inadequate for this purpose. Also a step-wise design approach that would help to master complexity and shorten development times is currently lacking.\ud
Standards are necessary since individual users of distributed system applications prefer to be independent on any particular manufacturer or vendor when procuring products, while manufacturers prefer to have maximum implementation freedom when developing such products. An ïżœopenïżœ protocol standard defines necessary and sufficient conditions for system parts to interact, such that the system parts can be implemented independently of each other.\ud
ISO and ITU-TSS base the development and definition of protocol standards on a ïżœreference modelïżœ, called the Reference Model for Open Systems Interconnection (OSIRM). This model comprises a rudimentary form of a design approach and a reference architecture that can be derived with this approach. According to the OSI-RM, the overall application protocol functionality is distributed over three hierarchical protocol layers. Each layer has been assigned a specific functionality, except the highest layer, the Application\ud
Layer, which is made responsible for all remaining protocol functions. Because the functionality of the Application Layer is not delimited it cannot, as opposed to the other layers, be covered by a single protocol standard or a fixed set of protocol standards. Several identified sets of Application Layer protocol functions are defined by separate Application Service Elements (ASEs).\ud
The appropriateness of the OSI-RM for the development and definition of application protocol standards can be criticized on a number of points:\ud
- the reference architecture defined by the OSI-RM is not flexible enough to adequately cope with the diversity of interaction requirements of distributed applications.\ud
- some design concepts are not clearly defined, thus prohibiting their effective application to structuring problems;\ud
- the relationship between high level application requirements and proposed application protocol solutions is unclear;\ud
- the development of application protocol standards generally takes a long time.\ud
This thesis aims at the development of a methodology for the design of application protocols, including application protocol standards, and so addresses the problems mentioned above. The following contributions are made to achieve this aim:\ud
- design quality criteria are proposed that can be used to guide design decisions and to evaluate designs;\ud
- OSI design decisions and design concepts with respect to application protocols are evaluated;\ud
- general-purpose, elementary design concepts are proposed;\ud
- milestones in the application protocol design process are presented;\ud
- behaviour composition and structuring techniques are developed that can be used to represent design results corresponding to the identified milestones;\ud
- design methods are proposed to support the correct performance of design steps between milestones;\ud
- a flexible reference architecture is proposed.\ud
A (potential) result of the design methodology is that layered application protocol hierarchies can be avoided if they are not required by the class of distributed applications that must be supported
Projeto de sistemas utilizando construçÔes predefinidas aplicadas a gerencia de redes : a biblioteca biblotos
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro TecnologicoEsta dissertação apresenta uma abordagem para o projeto de sistemas de gerĂȘncia de redes de computadores que emprega uma biblioteca de construçÔes predefinidas (a biblioteca bibLOTOS), realizadas com o uso da TĂ©cnica de Descrição Formal LOTOS. A biblioteca, implementada em banco de Dados ACCESS 2.0, inclui construçÔes em LOTOS BĂĄsico, ACT ONE e LOTOS Completo. O emprego da bibLOTOS, assim como do mĂ©todo a ela associado, sĂŁo ilustrados com o projeto de um sistema de gerĂȘncia proativa de redes. Ferramentas LOTOS sĂŁo utilizadas para a validação das especificaçÔes
Broker de comunicação em protocolos de comunicação para a saĂșde
EstĂĄgio realizado na Siemens, S. A. e orientado pelo Eng.Âș AntĂłnio MartinsTese de mestrado integrado. Engenharia InformĂĄtica e Computação. Faculdade de Engenharia. Universidade do Porto. 200
Safety and Reliability - Safe Societies in a Changing World
The contributions cover a wide range of methodologies and application areas for safety and reliability that contribute to safe societies in a changing world. These methodologies and applications include: - foundations of risk and reliability assessment and management
- mathematical methods in reliability and safety
- risk assessment
- risk management
- system reliability
- uncertainty analysis
- digitalization and big data
- prognostics and system health management
- occupational safety
- accident and incident modeling
- maintenance modeling and applications
- simulation for safety and reliability analysis
- dynamic risk and barrier management
- organizational factors and safety culture
- human factors and human reliability
- resilience engineering
- structural reliability
- natural hazards
- security
- economic analysis in risk managemen