{"title":"Agent-oriented modelling and specification of Web services","authors":"Hong Zhu, L. Shan","doi":"10.1109/WORDS.2005.14","DOIUrl":"https://doi.org/10.1109/WORDS.2005.14","url":null,"abstract":"Web services (WS) provide a technology for integrating applications over the Internet. This paper proposes a multi-agent conceptual model of WS and an agent-oriented modelling and formal specification method to address the difficulties in developing WS applications. The paper presents a graphic model of the general architecture of WS in agent-oriented modelling language CAMLE and an abstract specification in the formal specification language SLABS. It also illustrates how agent-oriented modelling and formal specification can be applied to the development of WS applications by an example of online auction WS and its requester application. It is shown that models and formal specifications enable software engineers to specify not only the service provider's functionality and behaviour, but also the requirements and restrictions on service requesters' behaviour. Such semantic information is crucial for the success of dynamic integration of WS.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126934275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Specification-based verification and validation of Web services and service-oriented operating systems","authors":"W. Tsai, Yinong Chen, R. Paul","doi":"10.1109/WORDS.2005.51","DOIUrl":"https://doi.org/10.1109/WORDS.2005.51","url":null,"abstract":"Service-oriented architecture (SOA) and Web services (WS) have received significant attention recently. Even though WS are based on open standards and support software interoperability, but the trustworthy issues of WS has actually limited the growth of WS applications as organizations do not trust those WS developed by other vendors and at the same time they do not have access to the source code. This paper addressed this issue by proposing several solutions including specification-based verification and validation, collaborative testing, and group testing. The key concept is that it is possible to provide a comprehensive evaluation of WS even if their source code is not available.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116614300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhancing DNS security using the SSL trust infrastructure","authors":"C. Fetzer, G. Pfeifer, T. Jim","doi":"10.1109/WORDS.2005.33","DOIUrl":"https://doi.org/10.1109/WORDS.2005.33","url":null,"abstract":"The main functionality of the domain name system (DNS) is to translate symbolic names into IP addresses. Due to the criticality of DNS for the proper functioning of the Internet, many improvements have been proposed for DNS in terms of security and dependability. However, the current secure DNS (DNSSEC) standard has still several problems that need further consideration. For example, online updates and denial of service attacks are not sufficiently addressed. These problems are serious obstacles that might prevent DNSSEC from replacing the traditional DNS. In this paper we discuss several of these technical and economic problems. To address these issues, we propose a simple extension to the existing DNS. It is SSL based and individual domains can decide independently of each other if and when to adopt the extensions. We show how to implement these extensions with the help of a simple proxy DNS server.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128743187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of fault-tolerant distributed Web systems","authors":"Y. Hong, J. No, In Han","doi":"10.1109/WORDS.2005.35","DOIUrl":"https://doi.org/10.1109/WORDS.2005.35","url":null,"abstract":"Replication of information among multiple servers is necessary to service requests for Web application such as Internet banking. A dispatcher in distributed Web systems distributes client requests among Web application servers and multiple dispatchers are also needed for fault-tolerant Web services. In this paper, we describe issues related to building fault-tolerant distributed Web systems. We evaluate the performance of fault-tolerant distributed Web systems based on replication. Our evaluation is conducted on LVS (Linux Virtual Server) and the Apache Web server using the request generator, LoadCube. We show some performance measurements for the systems.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126356697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An adaptable security framework for service-based systems","authors":"S. Yau, Yisheng Yao, Zhaoji Chen, Luping Zhu","doi":"10.1109/WORDS.2005.15","DOIUrl":"https://doi.org/10.1109/WORDS.2005.15","url":null,"abstract":"A major advantage of service-based computing technology is the ability to enable rapid formation of large-scale distributed systems by composing massively available services to achieve the system goals, regardless of the programming languages and platforms used to develop and run these services. In these large-scale service-based systems, various capabilities are provided by different organizations and interconnected by various types of networks, including wireless (infrastructure or ad hoc) and wired networks. For these systems which often involve multiple organizations, high confidence and adaptability are of prime concern to ensure that users can use these systems anywhere, any time, through various devices, knowing that their confidentiality and privacy are well protected under various situations. In this paper, an adaptable security framework for large-scale service-based systems is presented. It includes a core ontology and a logic-based situation-aware security specification language for specifying dynamic security policies for service-based systems, an approach to policy conflict detection and resolution, and tools for generating and deploying security agents to enforce security policies. With this framework, various parties of large-scale service-based systems can rapidly specify, update, verify, and enforce security policies in service-based systems to meet their security requirements under various situations.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123672817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Specification, analysis and implementation of architectural patterns for dependable software systems","authors":"S. Yau, S. Mukhopadhyay, Ramesh Bharadwaj","doi":"10.1109/WORDS.2005.50","DOIUrl":"https://doi.org/10.1109/WORDS.2005.50","url":null,"abstract":"Ensuring dependability of distributed applications is a difficult problem since developers must carefully consider issues such as network and node failures, deadlocks, live-locks, starvation, distributed coordination, and synchronization. The creation of architectural patterns for dependable software systems can provide effective guidelines, similar to design patterns, to system architects. In this paper, we present an agent specification language, associated tools, and agent-based middleware for specifying, analyzing and implementing architectural patterns for dependable software systems. The language we present is an extension of the secure operations language (SOL), which supports the behavioral specification of agents in addition to specification of agent interfaces, agent composition, and inter-agent interactions. Extended SOL can be used in the design of architectural patterns that implement the security, real-time, and fault-tolerance requirements of a given application. SOL also supports early and automated analyses of an application's functional requirements with respect to performance critical properties. Further, the language has a precisely defined semantics for composition, which enables the automated analysis of architectural designs and the impact of design choices on dependability requirements. The agent-based middleware secure infrastructure for networked systems (SINS), being developed at the Naval Research Laboratory, enables the rapid development and deployment of dependable distributed applications. Architectural patterns specified in extended SOL can be used to automatically derive an implementation, and to assign SINS agents to processors that constitute the distributed execution environment.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115022544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A framework for preparing experimental evaluation of rerouting mechanisms","authors":"R. B. Correia, L. Carmo, L. Pirmez, L. Bacellar","doi":"10.1109/WORDS.2005.6","DOIUrl":"https://doi.org/10.1109/WORDS.2005.6","url":null,"abstract":"Among the various QoS schemes that have already been proposed, rerouting critical flows is the most promising for its inherent ability to interface easily with management systems. To enhance the responsiveness, the operations performed by rerouting mechanisms should be done pro-actively. A pro-active network management using rerouting mechanisms was proposed by Correia et al., (2003). Recently, the proposed approach was selected to be deployed in an experimental fiber-optic gigabit backbone (GIGA project - sponsored by the Brazilian Research Network - RNP). The fundamental problem is how to specify critical factors and to develop a consistent set of tests for a complete field evaluation of the implementation. The constraints associated with this process are reduced deployment time and restricted availability of the network infrastructure for testing. This paper discusses a framework for deploying the rerouting mechanisms proposed by Correia et al. (2003) using DOE (design of experiments) analysis (Phadke). It is shown how rapidly some conclusions about performance, stability and interdependence upon the selection of design parameters can be taken through the use of DOE. Basically, MatLab models have been used to support the DOE analysis. This paper shows how the use of simple two and three-level factorial experimental designs can rapidly increase the designer's knowledge about the behavior of the mechanisms being studied.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123764767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Experiments with WCET-oriented programming and the single-path architecture","authors":"P. Puschner","doi":"10.1109/WORDS.2005.36","DOIUrl":"https://doi.org/10.1109/WORDS.2005.36","url":null,"abstract":"The single-path software/hardware architecture has been conceived with the goal to support real-time task execution with highly predictable timing. By using WCET-oriented programming (WCET... worst-case execution time) and then converting WCET-oriented code to single-path code we do not only aim at producing code with good temporal predictability but also target at a high worst-case performance. First experiments presented in this paper show that the combination of the two concepts yields indeed code with constant, hence fully predictable execution times. Further, these execution times are very competitive compared to the worst-case execution times of the alternative, non WCET-oriented solutions of the programming problems we investigated.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127165913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design and implementation of fault-tolerant transactional agents for manipulating distributed objects","authors":"Y. Tanaka, T. Enokido, M. Takizawa","doi":"10.1109/WORDS.2005.24","DOIUrl":"https://doi.org/10.1109/WORDS.2005.24","url":null,"abstract":"A transactional agent is a mobile agent which manipulates objects distributed in computers. A transactional agent is composed of routing and manipulation subagent. A way to move to computers is decided in the routing agent. Objects in each computer are manipulated in a manipulation agent. After visiting computers, a routing agent makes a decision on commitment by using the commitment condition. In addition, objects obtained from a computer in the manipulation agent have to be delivered to other computers where the transactional agent is performed. A schedule to visit computers is made from the input-output relation of manipulation agents. We discuss a model of transactional agent and implementation of a transactional agent on database servers and evaluate the transactional agents. We evaluate the transactional agent model in terms of accessing time compared with the traditional client-server model.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"03 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127188838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Autonomous agents and anticipative systems","authors":"M. Ramos, Félix F. Ramos","doi":"10.1109/WORDS.2005.20","DOIUrl":"https://doi.org/10.1109/WORDS.2005.20","url":null,"abstract":"In this paper we propose an artificial intelligence approach to real time simulation of a virtual community based on a multiagent system. Our approach is based on the work of Holland and Miller (1991), in which the authors propose that the system may be viewed as a complex dynamic adaptive system with a large number of different kinds of agents. In such environment, agents may take their decisions based on the anticipation of the future state of the world (Axelrod, 1997). In this paper, we explore how useful the concept of anticipation can be for real time simulation improving and facilitating decisions of the virtual entities. In this paper, we work with real time anticipative agents and where developed situations, actions, and changes in the world. This normal context in a virtual world is taken as a framework where an agent is able to compare previous learned situations, executed actions and obtained results; with current situations in order to decide which action could lead the agent to a situation with the best utility or satisfaction degree.","PeriodicalId":335355,"journal":{"name":"10th IEEE International Workshop on Object-Oriented Real-Time Dependable Systems","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128774978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}