Stefan Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic-Based Approach. In Protocol Specification, Testing, and Verification PSTV'95. Chapman & Hall, 1995.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....maximum allowed response times or to describe timing constraints imposed by the system environment, e.g. minimum intervals between external events. In a work around like approach, expressiveness is improved in combining functional specification languages with real time temporal logic formulas [Leu95, PB98] Applicability however remains limited due to the cryptic appearance of temporal logic languages. In a similar solution comparable to this work, annotations to the system specification are proposed in [SSD97] Beneath mapping, resource, and cost requirements, the so called SDL# allows to ....

....especially for the domain of real time systems is criticized in theoretical computer science [Hin98b, Hin98a] Main points of criticism include: 1. Expressiveness to capture real time requirements that are complementary to the functional description of a real time system is poor in SDL [Leu95] 2. Its asynchronous message passing communication scheme which allows a loose coupling of independent system parts (a sender will never be blocked through a non ready to communicate receiver) is unsuited for real time systems because the delay until the receiver proceeds its execution can ....

Stefan Leue. Specifying real--time requirements for SDL specifications --- a temporal logic--based approach. In Protocol Specification, Testing, and Verification PSTV'95. Chapman & Hall, 1995. 10, 17

....methods often do not separate simulated or model time from run time. For example, deriving SDL [22] specifications from UML diagrams or approaches based on ROOM [17] relying on tools like ObjectTime or RoseRT suffer from the problem that hard real time behaviour can not be modelled adequately [7]. This is because time is not an inherent aspect of SDL and ROOM models. As a consequence, these approaches are less suited for adequately analysing for example dedicated hardware systems. Probabilistic behaviour can be specified in SDL and ROOM using a proper random number generator. However, ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic-based Approach. In: P. Dembinski and M. Sredniawa (Eds.), Protocol Specification, Testing and Verification XV, pp. 19--34. Chapman and Hall, London, 1997.

....mechanism that is able to access a global clock referring to the current moment in time. However the delay between the pointof time when a timer expires and the moment at which the SDL model reacts to this expiry is unbounded. Therefore SDL is not suitable for expressing hard real time behaviour [8]. In fact, the concept of time in is not an inherent property of a model in SDL but of the possible underlying execution engine or operating system. The same holds for the ROOM language. 4 Example In [20] we have shown the suitability of the SHE method and POOSL language for the specification ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic-Based Approach. In P. Dembinski and M. Sredniawa, editors, Protocol Specification, Testing and Verification XV, pages 19--34, London, 1997. Chapman & Hall.

....the supporting tools to the detriment of the specification side. Several proposals already exist to extend SDL with real time features. We can mention for example the works carried out on performance evaluation ( 9,15] 17] 14] on schedulability analysis ( 4] or on real time requirements ([13]) In this paper we are more concerned with the use of SDL as a specification language for real time systems and its application for formal validation. In particular, one of the important question we address is what kind of real time features should be modeled in SDL and at which level of ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications -- A Temporal LogicBased Approach. In Proceedings of the Fifteenth International Symposium on Protocol Specification, Testing, and Verification PSTV'95. Chapmann & Hall, 1995.

....units. Test events are executed instantaneously. For the definition of an operational semantics of real time TTCN we adopted timed transition systems [7] A number of techniques for the specification of real time constraints have been proposed: time Petri Nets [2, 15] LOTOS [1, 6, 12, 17] SDL [6, 13] and ESTELLE [4] As in the cited literature, our approach allows the timing of actions relative to the occurrence of previous actions. The difference of the cited approaches and ours is that the former are used for the specification of functional and real time requirements of systems whereas our ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic Based Approach. Protocol Specification, Testing and Verification XV, 1995.

....execution (EET ) and a latest execution time (LET ) Informally, a test event may be executed if it has been continuously enabled for at least EET units and it must be executed if it has been continuously enabled for LET units. Test events are executed instantaneously. Our approach is similar to [2, 3, 4, 7, 11, 12, 14, 17]. The paper proceeds as follows: The next two sections introduce TTCN and real time TTCN, respectively. A discussion of the features of real time TTCN is done in Section 4, where real time TTCN is used for the definition of test cases for the generic cell rate algorithm used for traffic control ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic Based Approach. In Protocol Specification, Testing and Verification XV, 1995.

.... techniques for the specification of real time constraints have been proposed which are besides others: time Petri Nets (Berthmieu et al. 1991, Merlin et al. 1976) and extensions of LOTOS (Bowman et al. 1994, Hogrefe et al. 1992, Lonard et al. 1994, Quemada et al. 1987) SDL (Hogrefe et al. 1992, Leue 1995) and ESTELLE (Fischer 1996) As in the cited literature, our approach allows the timing of actions relative to the occurrence of previous actions. The difference between the cited approaches and ours is that real time TTCN is a hybrid method used for the specification of properties of test systems ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic Based Approach. In Protocol Specification, Testing and Verification XV, 1995.

....in [19,23] The basic approach to introduce real time into TTCN is by annotating TTCN statements. This approach is straightforward and has been used in several other approaches such as time Petri Nets [9,36] timed automata [1] temporal communicating systems [13] LOTOS [11,18,30,42] SDL [18,31] and ESTELLE [17] too. As in the cited literature, our approach allows the timing of actions relative to the occurrence of previous actions. Timed transition systems are the foundation for an operational semantics for real time TTCN. We found timed transition systems a suitable model for ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic Based Approach. In P. Dembinski, M. Sredniawa, editors, Protocol Specification, Testing and Verification XV, Chapman & Hall, 1996.

....implementations of the same functional interface. Moreover, TINA ODL does not support refinement of QoS specifications, which is an essential concept in an objectoriented setting. There are a number of languages that support QoS specification within a single QoS category. The SDL language [22] has been extended to include specification of temporal aspects. The RTSynchronizer programming construct allows modular specification of real time properties [15] These languages are all tied to one particular QoS category. In contrast, QML is general purpose; QoS categories are user defined ....

S. Leue. Specifying Real-Time Requirements for SDL specifications --- a temporal logic-based approach. Protocol Specification, Testing, and Verification XV. Proceedings of the Fifteenth IFIP WG6. June, 1995.

....of this paper and discusses some future work. 2. THE CONCEPT OF TIME IN SDL It is by now widely accepted that SDL is not well suited for the definition of hard real time requirements. There are a number of papers about SDL which have a critical look at the real time concept in SDL (e.g. 8] [13], 15] and discuss the expressiveness of real time properties in SDL. However, a crucial point has not yet been discussed: the relationship between the progress of time and the behaviour of a system specified by SDL. Analysing the behaviour of SDL specifications we had to learn that the time ....

Stefan Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic-Based Approach. In Protocol Specification, Testing, and Verification PSTV'95. Chapman & Hall, 1995.

....Forschungs Gemeinschaft (DFG) project Syslab the process as an ordinary input signal. When a timer is no longer needed, it can be reset before its expiration, to avoid spurious expirations. Unfortunately, these timing facilities are not precisely defined in the SDL and ROOM semantics [Hin96, Leu95, BB91, SGW94] and therefore implementation dependent. Practical experience has shown that the SDL timing facilities behave well only if the tolerance intervals are at least 100 times the average instruction time of the CPU used for the implementation [OFMP 94] Moreover, these timing ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic-Based Approach. In Proceedings of the Fifteenth International Symposium on Protocol Specification, Testing, and Verification PSTV'95. Chapmann & Hall, 1995.

....QoS specifications, but it is unclear what constraints they enforce to ensure conformance. QoS specifications are exchanged as instantiations of IDL types without any particular structure. There are a number of languages that support QoS specification within a single QoS category. The SDL language [14] has been extended to include specification of temporal aspects. The RTSynchronizer programming construct allows modular specification of real time properties [20] These languages are all tied to one particular QoS category. In contrast, QML is general purpose; QoS categories are user defined ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications---a Temporal Logic-Based Approach. Protocol Specification, Testing, and Verification XV. in Proceedings of the Fifteenth IFIP WG6 . June, 1995.

....and supports structural and hierarchical modeling. Most approaches to support performance evaluation of SDL systems are based on extensions of the SDL language itself to specify various performance aspects. Extensions to SDL to specify performance requirements are described in [14] and [6] In [13], the separate specification of performance requirements with a temporal logic is proposed. Most approaches known from the literature specify the resource requirements for the execution of the SDL system with extensions added to SDL itself (e.g. the approaches described in [1,2,5,6,14,19] A ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications -- ATemporal Logic-Based Approach. Proc. 15. Int. Symp. on Protocol Specification, Testing and Verification (PSTV'95), P. Dembinski, M. Sredniawa (Ed.), June 1995.

....to express real time requirements. In standard SDL, this is done by the timer concept. But, since with the exception of the timer part there are no assumptions about the timed behaviour of (the other parts of) an SDL specification, the timer concept leads to certain anomalies. e.g. as Leue [13] points out, in some cases no finite bound of the delay between the point of time when a timer expires, and the moment at which the SDL specification reacts to the expiry can be found. As a solution in this paper an extension of SDL specifications by real time assertions is suggested. The ....

....to other states, may be added to SDL specifications. This approach enables probabilistic validation and performance evaluation of SDL specifications based on stochastic processes. Hence, the domain of properties to be analysed using this approach is rather different from the one presented here. In [13], quantitative aspects of SDL systems are modelled by additional specifications in terms of real time extended temporal logic (MTL ) formulae. The allowed behaviour of an SDL system is given via a global state transition system, and is constrained by the MTL formulae. In this approach, SDL system ....

S. Leue, Specifying Real-Time Requirements for SDL Specifications -- a Temporal Logic-Based Approach, Research Paper, University of Waterloo, Canada, 1996.

....its timing constraints are expressed in temporal logic. The real time system is then characterized by all the timed state sequences produced by the automata algebra which in addition fulfill the temporal logic formulas. Bowman et al. 1994) describe this for LOTOS in conjunction with QTL and (Leue, 1995) for SDL with MTL. We will employ this approach for the definition of Real Time Estelle. Suitability for QoS specification. We note that for most QoS parameters, a purely operational semantics, where temporal requirements can only be related to single transitions (as e.g. in Timed Transition ....

....To these state components, we add predicates SENDING OF (p.m) and RECEIVING OF (p.m) which are true when message m has been sent (output statement) over resp. received (when clause) at interaction point p during the last transition. Such predicates already proved very useful for QoS specifications (Leue, 1995). The new instance operator [ allows counting of messages sent or received at a certain IP. 2. Time is added to Estelle s state sequences by adding just one component to the state description. This time component is a positive integer variable, and the only restriction for its value is the ....

Leue, S. (1995). Specifying Real-Time Requirements for SDL Specifications --- A Temporal Logic-Based Approach. In (Dembi'nski and ' Sredniawa, 1995), pages 19--34.

....use and importance of SDL there is a real need for a natural formal semantics of SDL to be developed which can be used to analyse and verify system specifications. To this end there have been several attempts in the past few years including semantics based on: process algebra [3] temporal logic [14] and duration calculus [17] stream processing functions [5] 10] and [9] With the exception of [9] these semantics focus on different views of SDL and formalize different parts of the language. In our opinion SDL still lacks a formal semantics which integrates within one unifying framework all ....

....use of Maude s object oriented features. Though our semantics allows us to describe real time systems, its operational style makes it difficult to express more complex real time requirements. It therefore may be reasonable to consider in future work combining our approach with temporal logic (see [14] and [17] and to consider extending the SDL syntax accordingly. Finally we note that SDL specifications are closely related to message sequence charts (MSCs) 11] In future work we intend to investigate the relationship between these two real time FDTs using the formal semantics presented in ....

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal LogicBased Approach. Procs. of 15th Int. Symp. on Protocol Specification, Testing, and Verification, Chapman and Hall, 1995.

....formal methods, that have been pointed out, can be hints on directions, in which it is useful to improve a formal method. Some examples are: ffl Improve the expressiveness of statecharts and SDL with respect to temporal properties. This is already an area of active research, see e.g. KP92, Dei96, Leu95] Most temporal properties can already be described by using timeouts, but not in a very clear way. Therefore, more suitable temporal operators should be available. ffl There are few guidelines and rules which are specific for statecharts. But, as can be seen from the answers given, statecharts ....

S. Leue. Specifying real-time requirements for SDL specifications - a temporal logic-based approach. In Proc. of 15th Intl. Symp. on Protocol Specification, Testing, and Verification PSTV'95. Chapman and Hall, 1995.

....examples in Section 8. Finally, Section 9 concludes the paper with a comparison of the approaches, perspectives for verification, automatic implementation and the incorporation of stochastic expressiveness. Precursors of this work have appeared in [26] which introduces Real Time Estelle, and in [52,53] in which the SDL based approach was first presented. 2 Related Work Basic models. Many of the existing models used to specify functional system behavior operational techniques such as automata, Petri nets, process 2 algebra, and descriptive techniques like logics have been enriched by ....

S. Leue. Specifying real-time requirements for SDL specifications -- a temporal logic-based approach. In P. Dembi'nski and M. ' Sredniawa, editors, Proceedings of the Fifteenth International Symposium on Protocol Specification, Testing, and Verification PSTV'95. Chapman & Hall, 1995.

....examples in Section 8. Finally, Section 9 concludes the paper with a comparison of the approaches, perspectives for verification, automatic implementation and the incorporation of stochastic expressiveness. Precursors of this work have appeared in [27] which introduces Real Time Estelle, and in [54,55] in which the SDL based approach was first presented. 2 Related Work Basic models. Many of the existing models used to specify functional system behavior operational techniques such as automata, Petri nets, process algebra, and descriptive techniques like logics have been enriched by means ....

....are to interpret SDL specifications and Temporal Logic formulae on common model theoretic grounds. Second, our approach to a semantics definition is exemplary in nature and intended to cover only a small subset of the SDL language. A more extensive description of our definitions can be found in [55,28]. Related work. Our definitions here are close to the Basic Transition Systems of [60] Our pSTS models can be seen as a logic based formulation of Extended Finite State Machines (EFSM) 57] The modeling of SDL processes as EFSMs has been suggested in [7] and [68] However, as we will see ....

S. Leue. Specifying real-time requirements for SDL specifications -- a temporal logic-based approach. In P. Dembi'nski and M. ' Sredniawa, editors, Proceedings of the Fifteenth International Symposium on Protocol Specification, Testing, and Verification PSTV'95. Chapman & Hall, 1995.

No context found.

Stefan Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic-Based Approach. In Protocol Specification, Testing, and Verification PSTV'95. Chapman & Hall, 1995.

No context found.

S. Leue. Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic-Based Approach. In Proceedings of the Fifteenth International Symposium on Protocol Specification, Testing, and Verification, Chapmann & Hall, 1995.

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S. Leue. "Specifying Real-Time Requirements for SDL Specifications - A Temporal Logic-Based Approach". In Proceedings of the Fifteenth International Symposium on Protocol Specification, Testing, and Verification PSTV'95. Chapmann & Hall, 1995.

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Leue, S. SPECIFYING REAL-TIME REQUIREMENTS FOR SDL SPECIFICATIONS -- A TEMPORAL LOGIC-BASED APPROACH. In: Proceedings of the 15th IFIP WG6.1 International Symposium on Protocol Specification, Testing and Verification, Warshaw, June 1995.

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S. Leue. Specifying Real-Time Requirements for SDL Specifications -- A Temporal LogicBased Approach. Proc. 15. Int. Symp. on Protocol Specification, Testing and Verification (PSTV'95), P. Dembinski, M. Sredniawa (Ed.), June 1995.

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