Rolv Bræk - Academia.edu (original) (raw)

Papers by Rolv Bræk


ABSTRACT An abstract is not available.

Telektronikk (to appear, 2009

1 Introduction Creating systems by plugging together reusable building blocks is a fundamental en... more 1 Introduction Creating systems by plugging together reusable building blocks is a fundamental engineering princi-ple that is used in a wide range of domains, especially in electronics and mechanics. However, looking at methods and tools that are employed in software and ...

This paper argues for three fundamental properties that every modeling approach should posses. It... more This paper argues for three fundamental properties that every modeling approach should posses. It presents a simple classification schema for models and proposes some comparison criteria. Finally it provides some reflection on properties currently in the CMA ”parking

Lecture Notes in Computer Science, 2001

The purpose of Implementation Design is to bridge the gap between an abstract system, e.g. in SDL... more The purpose of Implementation Design is to bridge the gap between an abstract system, e.g. in SDL, and its implementation in hardware and software. Expressing the Implementation Design decisions is a general challenge in systems engineering. Notations have been defined to describe abstract models and implementations, but little work has been done to define a notation for Implementation Design. In

We consider here a UML 2 collaboration describing the structure of a service as a set of roles an... more We consider here a UML 2 collaboration describing the structure of a service as a set of roles and the sub-collaborations that take place between them. Such sub-collaborations are represented as UML collaboration uses, and can themselves be composite collaborations or elementary collaborations, which are no further decomposed. We assume the behavior of an elementary collaboration is described with the help of a UML 2 sequence diagram. The behavior of a composite collaboration is described as a choreography of its sub-collaborations. Such choreography is specified using an UML 2 activity diagram, where each nodes is a CallBehaviorAction that invokes the behavior associated with a collaboration type and made available via a collaboration use (in the diagram describing the structure of the composite collaboration). Given a choreography, we are interested in finding a set of communicating role behaviors whose joint behavior is precisely the specified by the choreography. Whenever it is ...

Lecture Notes in Computer Science, 2016

... This may well be true for methods based on similar conceptual abstractions, eg methods based ... more ... This may well be true for methods based on similar conceptual abstractions, eg methods based ... cation part of) realisations automatically, but this depends on the language and available tools. ... This may be partially caused by reluctance to introduce formal methods, espe-cially ...

The dynamic composition of services as visioned in a Plug-and Play approach requires new design a... more The dynamic composition of services as visioned in a Plug-and Play approach requires new design and valida- tion methods. We propose a service design based on the concept of roles. The feature of composite state newly introduced in SDL 2000 is used to model roles and their composition. We introduce a validation approach tightly integrated with the composition of roles. The approach takes advantage of the system structure. In that way, it will be possible to reuse the results of the analysis done before the modification of the system when a new component is introduced. Furthermore, as components may be bound dynamically at run-time, the analysis is defined such that it can be applied on state machine types - not only instances. 1I

Lecture Notes in Computer Science, 2006

In our service engineering approach, services are specified by UML 2.0 collaborations and activit... more In our service engineering approach, services are specified by UML 2.0 collaborations and activities, focusing on the interactions between cooperating entities. To execute services, however, we need precise behavioral descriptions of physical system components ...

models . Emphasis on abstract models and descriptions: Abstract descriptions leave out implementa... more models . Emphasis on abstract models and descriptions: Abstract descriptions leave out implementation specific details and let the developers focus on functionality. Domain Descriptions System Family descriptions Instance Descriptions Figure 1: IM activities, descriptions and languages Analysis Domain Analysis Requirements analysis Design Application design Framework design Architecture design Implementation Instantiation Configuration Building Testing Object Models Property Models Object Models Property Models Concrete system Specifications Implementation Instance configuration MSC, OMT/UML MSC, OMT/UML MSC, SDL SDL Design Models Introduction SISU Integrated Methodology - at a glance SISU report L-2001-7 SISU Modified: 1996-11-18 SISU 6 Property models . Focus on (external) properties: Objects are the building material from which systems and components are constructed. Property descriptions are used at an early stage of development to express the properties required from a sys...

CANDLE (Cooperative And Network Distributed Learning Environment) is a new European project suppo... more CANDLE (Cooperative And Network Distributed Learning Environment) is a new European project supported by European Telecommunications Schools members of EUNICE, and others partners as: BT, IOE, Siemens, . . . The project is supported by the EC within the IST Program.

IFIP Advances in Information and Communication Technology, 2000

This paper is about achieving open-ended flexibility using roles, types and objects. Unfortunatel... more This paper is about achieving open-ended flexibility using roles, types and objects. Unfortunately the term "role" is used to mean different things in different approaches, and it is not always clear how it relates to other important notions such as types or classes and objects. The first concern of this paper is therefore to clarify what roles are. The second is to outline how they can be utilised to achieve open-ended flexibility in systems and services. It does not go deeply into the technical details, but concentrates on overall principles and how they may be utilised in combination with existing methods and languages, in particular UML [OMG 99], [Rumbaugh 99], SDL [lTU 93] and MSC [ITU 96b].

Proceedings of the Second International Conference on Software Engineering and Formal Methods, 2004. SEFM 2004., 2004

ABSTRACT In this paper we present a method for describing Service Goals for peer-to-peer systems ... more ABSTRACT In this paper we present a method for describing Service Goals for peer-to-peer systems using UML 2. 0. We propose how to model services at a higher level than protocols and state machines, and how this modeling can relate to lower layers of abstraction. We show how this novel way of service specification can contribute to service validation and to dynamic discovery of peer-to-peer services.

Lecture Notes in Computer Science, 2005

This paper presents a validation approach that exploits the compositional properties of a system.... more This paper presents a validation approach that exploits the compositional properties of a system. Our results can be applied on systems modelled by state machines and asynchronous communication by message passing. We consider two axes of composition: horizontal composition across system components, and vertical composition within components. Along the horizontal axis, we reduce the complexity of validation analysis by using a projection technique that allows us to validate interactions between components pairwise. We further simplify by introducing a set of design rules that support the development of well-formed state machines. When these rules are enforced, we are able to apply a simplified compatibility checking algorithm. Along the vertical axis, validation is applied incrementally. Elementary component collaborations are validated first, then their composite.


ABSTRACT An abstract is not available.

Telektronikk (to appear, 2009

1 Introduction Creating systems by plugging together reusable building blocks is a fundamental en... more 1 Introduction Creating systems by plugging together reusable building blocks is a fundamental engineering princi-ple that is used in a wide range of domains, especially in electronics and mechanics. However, looking at methods and tools that are employed in software and ...

This paper argues for three fundamental properties that every modeling approach should posses. It... more This paper argues for three fundamental properties that every modeling approach should posses. It presents a simple classification schema for models and proposes some comparison criteria. Finally it provides some reflection on properties currently in the CMA ”parking

Lecture Notes in Computer Science, 2001

The purpose of Implementation Design is to bridge the gap between an abstract system, e.g. in SDL... more The purpose of Implementation Design is to bridge the gap between an abstract system, e.g. in SDL, and its implementation in hardware and software. Expressing the Implementation Design decisions is a general challenge in systems engineering. Notations have been defined to describe abstract models and implementations, but little work has been done to define a notation for Implementation Design. In

We consider here a UML 2 collaboration describing the structure of a service as a set of roles an... more We consider here a UML 2 collaboration describing the structure of a service as a set of roles and the sub-collaborations that take place between them. Such sub-collaborations are represented as UML collaboration uses, and can themselves be composite collaborations or elementary collaborations, which are no further decomposed. We assume the behavior of an elementary collaboration is described with the help of a UML 2 sequence diagram. The behavior of a composite collaboration is described as a choreography of its sub-collaborations. Such choreography is specified using an UML 2 activity diagram, where each nodes is a CallBehaviorAction that invokes the behavior associated with a collaboration type and made available via a collaboration use (in the diagram describing the structure of the composite collaboration). Given a choreography, we are interested in finding a set of communicating role behaviors whose joint behavior is precisely the specified by the choreography. Whenever it is ...

Lecture Notes in Computer Science, 2016

... This may well be true for methods based on similar conceptual abstractions, eg methods based ... more ... This may well be true for methods based on similar conceptual abstractions, eg methods based ... cation part of) realisations automatically, but this depends on the language and available tools. ... This may be partially caused by reluctance to introduce formal methods, espe-cially ...

The dynamic composition of services as visioned in a Plug-and Play approach requires new design a... more The dynamic composition of services as visioned in a Plug-and Play approach requires new design and valida- tion methods. We propose a service design based on the concept of roles. The feature of composite state newly introduced in SDL 2000 is used to model roles and their composition. We introduce a validation approach tightly integrated with the composition of roles. The approach takes advantage of the system structure. In that way, it will be possible to reuse the results of the analysis done before the modification of the system when a new component is introduced. Furthermore, as components may be bound dynamically at run-time, the analysis is defined such that it can be applied on state machine types - not only instances. 1I

Lecture Notes in Computer Science, 2006

In our service engineering approach, services are specified by UML 2.0 collaborations and activit... more In our service engineering approach, services are specified by UML 2.0 collaborations and activities, focusing on the interactions between cooperating entities. To execute services, however, we need precise behavioral descriptions of physical system components ...

models . Emphasis on abstract models and descriptions: Abstract descriptions leave out implementa... more models . Emphasis on abstract models and descriptions: Abstract descriptions leave out implementation specific details and let the developers focus on functionality. Domain Descriptions System Family descriptions Instance Descriptions Figure 1: IM activities, descriptions and languages Analysis Domain Analysis Requirements analysis Design Application design Framework design Architecture design Implementation Instantiation Configuration Building Testing Object Models Property Models Object Models Property Models Concrete system Specifications Implementation Instance configuration MSC, OMT/UML MSC, OMT/UML MSC, SDL SDL Design Models Introduction SISU Integrated Methodology - at a glance SISU report L-2001-7 SISU Modified: 1996-11-18 SISU 6 Property models . Focus on (external) properties: Objects are the building material from which systems and components are constructed. Property descriptions are used at an early stage of development to express the properties required from a sys...

CANDLE (Cooperative And Network Distributed Learning Environment) is a new European project suppo... more CANDLE (Cooperative And Network Distributed Learning Environment) is a new European project supported by European Telecommunications Schools members of EUNICE, and others partners as: BT, IOE, Siemens, . . . The project is supported by the EC within the IST Program.

IFIP Advances in Information and Communication Technology, 2000

This paper is about achieving open-ended flexibility using roles, types and objects. Unfortunatel... more This paper is about achieving open-ended flexibility using roles, types and objects. Unfortunately the term "role" is used to mean different things in different approaches, and it is not always clear how it relates to other important notions such as types or classes and objects. The first concern of this paper is therefore to clarify what roles are. The second is to outline how they can be utilised to achieve open-ended flexibility in systems and services. It does not go deeply into the technical details, but concentrates on overall principles and how they may be utilised in combination with existing methods and languages, in particular UML [OMG 99], [Rumbaugh 99], SDL [lTU 93] and MSC [ITU 96b].

Proceedings of the Second International Conference on Software Engineering and Formal Methods, 2004. SEFM 2004., 2004

ABSTRACT In this paper we present a method for describing Service Goals for peer-to-peer systems ... more ABSTRACT In this paper we present a method for describing Service Goals for peer-to-peer systems using UML 2. 0. We propose how to model services at a higher level than protocols and state machines, and how this modeling can relate to lower layers of abstraction. We show how this novel way of service specification can contribute to service validation and to dynamic discovery of peer-to-peer services.

Lecture Notes in Computer Science, 2005

This paper presents a validation approach that exploits the compositional properties of a system.... more This paper presents a validation approach that exploits the compositional properties of a system. Our results can be applied on systems modelled by state machines and asynchronous communication by message passing. We consider two axes of composition: horizontal composition across system components, and vertical composition within components. Along the horizontal axis, we reduce the complexity of validation analysis by using a projection technique that allows us to validate interactions between components pairwise. We further simplify by introducing a set of design rules that support the development of well-formed state machines. When these rules are enforced, we are able to apply a simplified compatibility checking algorithm. Along the vertical axis, validation is applied incrementally. Elementary component collaborations are validated first, then their composite.