Modular software model checking for distributed systems components

Keywords distributed systems, model checking, education. Today, distributed systems have developed complex components more. First, consider the software architecture of the components of a distributed system. The abstract components are then composed to form an abstract system to which a model checking. Layer of software that masks heterogeneity and provides a convenient programming model for application programmers. Software components are parts of a system or application.

The four layers are intersected vertically with the development phases. In a sense, this entire paper boils down to leveraging the domain knowledge of distributed systems to better modelcheck them. Model checking a networked system without the network. Baseline physical model hardware and software components located at networked computers communicate and coordinate their actions only by passing messages very simple physical model of a distributed system. How to design and analyze security of a software system composed of modules. Embedded systems distributed architectures raise other issues than limited shannon budget and costtocommunicate distributed control architectures cause artifacts that can be problematic for feedback control systems architectures such as ima and autosar aim at enabling modular development of systems in complex supplier chains. Upgrading the softwareof longlived, highlyavailable distributed systems is di cult. Transition in gas turbine control system architecture. The monitors placed in different parts of the model check that different components of the system operate properly. Apr 19, 2016 this solid state mcs 3233 from modular component systems was manufactured in during the late 1970s and into the very early 1980s. The system model can be verii ed against requirements formalized in ctl 12. A common practice to manage software complexity is to encapsulate the complexity using wellde. The development of the modular modeling system mms began with the establishment of a 3year cooperative agreement between the u. The abstract components are then composed to form an abstract system to which a model checking procedure is.

Abstraction for model checking modular interpreted systems. Pdf abstract model checking is an influential method to verify. A soa service is a discrete unit of functionality that can be accessed remotely and acted upon and updated independently, such as retrieving a credit card statement online. The user, then, manually provides only those parts of the model that. What does the architecture of a distributed system define and what issues are addressed when a system is to be engineered. In our interface specification language, component. Such systems are characterized by the distribution of hardware, software, and physical components for the control and automation systems implementation, following the trend to distributed. With the distributed file system replication component, dfsr, as the central theme, we present selected protocol problems and. Automated environment generation for software model. Transparent model checking of unmodified distributed. Composition of modular models for verification of distributed.

Model checking is a method that automatically determines whether a finite state system satisfies a temporal logic specification. Modular abstractions for verifying realtime distributed. Models and software model checking of a distributed file. Software model checking, state space reduction, dynamic interface reduction. One of the bene ts of restricting ourselves to lineartime logic as opposed to a more expressive logic such as ctl or the modal mucalculus is the ability to invoke the magic compositional. A fast model checker for finding heisenbugs in distributed. Based on mechatronic components a hierarchical application model for control software development has been proposed by 22. The secondary controller is a process controller or a communications controller, or both. They repay the effort by yielding better modular verification techniques. Aretskinhariton nasa glenn research center intelligent control and autonomy branch nasa glenn research center aiaa propulsion and energy 2014 july 28, 2014. The term modular can apply to both hardware and software. The control system developed for the commercial modular aeropropulsion system simulation 40k cmapss40k provides a veri. Model checking, automated abstraction, and compositional.

Concurrency bugs, model checking, distributed systems. Modeling and verification of reactive systems using rebeca. This solid state mcs 3233 from modular component systems was manufactured in during the late 1970s and into the very early 1980s. Modular, distributed, and embedded, asme turbo expo2010. Upgrading the softwareof longlived, highlyavailable distributed sys. The model should provide a formal model for composition 8 and specify how components interact and collaborate with each other. The process controller components of the system, the executive service, and the mailbox service are automatically installed on the primary system controller. For example, a typical distributed system is comprised. Modist is the first model checker designed for transparently checking unmodified distributed systems running on unmodified operating systems. Nces net conditions event systems are designed to model modular control software. Jul 01, 20 many purists used to laugh at the mcs brand. It is a reusebased approach to defining, implementing and composing loosely coupled independent components into systems.

Teaching rigorous distributed systems with efficient model checking. It is a reusebased approach to defining, implementing and composing loosely. Corba contemporary distributed systems isha padhy, department of cse, cbit, hyderabad 2 3. Leveraging this common practice, a model checker considers a target software system as consisting of a set of components, each with a well. Systems are modular mostly finitestate systems system components have well defined interfaces mostly synchronous execution 8 application of model checking to software verification complex data structures are used procedural or oo design nonfinite state systems system components do not have well defined interfaces.

It achieves this transparency via a novel architecture. Aug 24, 2016 physical model model that capture the hardware composition of a system in terms of computer and their interconnecting networks. Fundamental components in a distributed system 26 jul 2011. A modular framework for modeling hardware elements in. Componentbased software engineering cbse, also called components based development cbd, is a branch of software engineering that emphasizes the separation of concerns with respect to the wideranging functionality available throughout a given software system.

Current approaches to model checking distributed systems reduce the problem to that of model checking centralized systems. We have implemented an explicitstate model checker and applied it to a real software system to validate our prior, theoretical work on featureoriented verification. A process controller regulates the management and dispatching of server processing requests within the system to allow the system translation load and other processing functions to be distributed for fast and efficient throughput. Components are a means of breaking the complexity of software into manageable parts. Modular distributed modeling mdm of engineering structures performs static deflection analysis using traditional. Early distributed systems internetscale distributed systems.

The modular modeling system mms is an integrated system of computer software that has been developed to provide the research and operational framework needed to support development, testing, and evaluation of physicalprocess algorithms and to facilitate integration of userselected sets of algorithms into operational physicalprocess. Upgrading the software of longlived, highlyavailable distributed systems is difficult. Practical software model checking via dynamic interface reduction. Modular software upgrades for distributed systems springerlink. Early distributed systems emerged in the late 1970s and early 1980s because of the usage of local area networking technologies system typically consisted of 10 to 100 nodes connected by a lan, with limited internet connectivity and supported services e. In this work we present a verification methodology for realtime distributed systems, based on their modular decomposition into processes. Security confidentiality, integrity, availability policy, model, mechanism access control models information flow models module types and connection mechanisms survey framework surveyed techniques assessments and research issues. While crystalball is based on macemc and thus checks only systems written in the mace language, its core technique may be portable to modists model checking framework to improve the reliability of general distributed systems. In this paper we elaborate on the corresponding theory of the modular veri. Software and hardware service layers in distributed systems.

Fundamental distributed system models fundamental models fundamental models description of properties that are present in all distributed architectures. Upaal is an integrated environment to model and verify realtime systems. The sut is a process that a tester wants to verify in a software model checker. Experimental results on various distributed systems show the capability and scalability of cachebased model checking. Interaction models issues dealing with the interaction of process such as performance and timing of events. This provide us a language for modeling globally asynchronous and locally synchronous systems. Serviceoriented architecture soa is a style of software design where services are provided to the other components by application components, through a communication protocol over a network. Hierarchical control modelling architecture for modular. Unit 1 architecture of distributed systems 1 architecture of distributed systemsintroductiona distributed system ds is one in which hardware and software components, located at remote networked computers, coordinate and communicate their actions only by passing messages. The complexity of model checking is wellknown, yet costeffective analyses have been achieved by exploiting, for example, naturally occurring abstractions and semantic properties of a target software artifact. The influence of software module systems on modular. We compare modist to other closely related implementationlevel model checkers. Stylebased modeling and verification of fault tolerance service oriented architectures.

Stylebased modeling and verification of fault tolerance. This feature and also the eventdriven nature of the computation are exploited to introduce a modular verification approach in order to overcome the state explosion problem in model checking. Spin 6 is an onthefly linear temporal logic ltl model checker based on an automatatheoretic verification method, which is used to formally verify models of distributed software systems. However, most model checking techniques require that a system be described in a modeling language. Index terms software model chec king, software veri. Modular software design, for example, refers to a design strategy in which a system is composed of relatively small and autonomous routines that fit together. Practical software model checking via dynamic interface. A framework for verification of distributed java applications. Pdf a symbolic model checking approach in formal verification of. Each component hides the complexity of its implementation behind an interface. Appears in the proceedings of the international symposium on software testing and analysis issta 15.

Architecture distributed systems tend to be very complex. Further, the time and space requirements with these techniques may in practice be polynomial in the number of components of the system. Given a distributed system, each of its components is reduced by abstracting away from details that are irrelevant for the required specification. A distributed system is a system whose components are located on different networked computers, which communicate and coordinate their actions by passing messages to one another. Modular programming, in the form of subsystems particularly for io and software libraries, dates to early software systems, where it was used for code reuse. Currently, my research group is working on an interface specification language based on grammars for modular software model checking 9. What are the components of distributed control system. Distributed computing is a field of computer science that studies distributed systems. Adapting a model checking tool to exploit this kind of domain knowledge often requires indepth knowledge of the tools implementation. After clearly specifying components, there needs a underlying computation model for component based software development. Well, there are probably still some that laugh at it but less loudly then before. A component is a modular unit with welldefined required and provided interfaces. In the last several weeks i have had a surprising number of conversations about the fundamental building blocks of a large webbased system. Model checking algorithms have been successfully used to verify complex systems.

The organization of a distributed system is primarily about defining the software components that constitute the system. A modular framework for modeling hardware elements in distributed engine control systems alicia m. Application of model checking to hardware verification simple data structures are used systems are modular mostly finitestate systems system components have well defined interfaces mostly synchronous execution 8 application of model checking to software verification complex data structures are used procedural or oo design. It is not possible to upgrade all the nodes in a system at once, since some nodes may be unavailable and halting the system for an upgrade is unacceptable. Unit verication targets a single component of a distributed application and requires that the user. Modular software model checking for distributed systems. Physical model model that capture the hardware composition of a system in terms of computer and their interconnecting networks.

We present a frontend tool for translating rebeca to the languages of existing model checkers in order to model check rebeca models. Tells us how software components should be organized and how they should interact. This reduces the complexity of software development, maintenance, operations. An example of a particularly challenging distributed system is multimaster, optimistic. One component required in an hil simulation system is a high. For modeling, timed automata which can be extended are used. Aretskinhariton nasa glenn research center, cleveland, oh 445, usa progress toward the implementation of distributed engine control in an aerospace. Challenges for modeling distributed systems and creating a versatile hardwareintheloop hil system migration from a centralized to a distributed modeling approach decomposing an engine model modeling of control system components creating a library of reusable modeling components. This work proposes a method for improving the scalability of modelchecking compositions in the bottomup construction of abstract components. Net remoting services transactions, persistence, naming, etc. Components can be swapped in and out like the interchangeable parts of a machine.

Interface grammars for modular software model checking. We believe that with appropriate tool support, domain experts will be able to develop efficient model checking based analyses for a variety of software related models. Automated environment generation for software model checking oksana tkachuk, matthew b. Software component an overview sciencedirect topics. Modular software model checking for distributed sys tems. The opposite of a modular architecture is an integrated architecture, in which no clear divisions exist between components. Stateevent based software model checking 3 the stateeventbased formalism presented in this paper is suitable for both sequential and concurrent systems. Component based software engineering cbse, also called components based development cbd, is a branch of software engineering that emphasizes the separation of concerns with respect to the wideranging functionality available throughout a given software system. Into which category, model, architecture or engineering, would you place the following statement.

Ccs concepts software and its engineering model checking. I thought id write up the main bits of a good way to do it. Geological survey and the university of colorado at boulders center for advanced decision support for water and environmental systems cadswes in september 1989. Server system controller and user interface clients in a microsoft windows workgroup model in. An extensible and highly modular software model checking. Apr 08, 2019 it does this with the aid of input devices such as sensors, that respond in some way to this information and then uses electrical energy in the form of an output action to control a physical process or perform some type of mathematical operation o. The di culties in doing so are even more pronounced when reasoning about modular software, such as concurrent or component based sequential programs.

Boolean and cartesian abstraction for model checking c programs. It systematically explores a distributed systems execu tions by enumerating the actions, failures, and timers ex posed by the other modist components. It is a response to the limitations presented by the traditional mainframe clienthost model, in which a single mainframe provides shared data access to many dumb terminals. Modular software model checking for distributed systems ijircce. Software verification, model checking, model extraction, software testing. Efficient computeraided verification of parallel and. Our approach enables model checking to be executed in a modular fashion by replacing different components in the software system with environment models generated from their interfaces. The lower two layers comprise the platform, such as intel x86windows or powerpcmacos x, that provides oslevel services to the upper layers the middleware sits between the platform and the application and its purpose is to mask heterogeneity and provide a consistent programming. We have integrated demeter into two existing model checkers. In our presentation, well focus on that definitiondimension of proof checking. Migration from a centralized to a distributed modeling approach decomposing an engine model modeling of control system components creating a library of reusable modeling components establishing a template for modeling distributed systems working toward a hardwareintheloop hil system simulation benchmarking and. Jul 26, 2011 fundamental components in a distributed system 26 jul 2011. To apply model checking to software, it is necessary to specify often complex properties on the nitestate abstracted models of computer programs.

Model checking is emerging as a popular technology for reasoning about behavioral properties of a wide variety of software artifacts including. The components interact with one another in order to achieve a common goal. It is critical to properly organize these systems to manage the complexity. Mcs didnt actually manufacture their equipment and there has been quite a bit of discussion online as to who made their receivers. For producerconsumer interaction style, dataflow model is a natural candidate computation model. Modular systems in computer science are divided into components or modules with welldefined interfaces and dependencies as small as possible.