• The Journal of the Korea institute of electronic communication sciences
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• v.1 no.1
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• pp.20-26
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• 2006

One of the computer application fields which started showing noticeable new growth trends in recent years is the real time communication distributed computing application field. Object -oriented(OO) real time(RT) distributed computing is a form of real-time distributed computing realized with a distributed computer system structured in the form of an object network. In this paper, we describes the application environment as the DHS (distributed high-precision simulation) with TMO structure. The TMO scheme is aimed for enabling a great reduction of the designer's effort in guaranteeing timely service capabilities of distributed computing application systems. It has been formulated from the beginning with the objective of enabling design-time guaranteeing of timely action. In the real time simulation techniques based on TMO object modeling, we have observed several advantages to the TMO structuring scheme. TMO object modeling has a strong traceability between requirement specification and design, cost-effective high-coverage validation, autonomous subsystems, easy maintenance and flexible framework for requirement specification.

• KIPS Transactions on Computer and Communication Systems
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• v.2 no.9
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• pp.369-380
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• 2013

Recently, role-based distributed system models have been proposed to support adaptive interactions in ubiquitous application environment. A Role-based distributed model regards an application as an organization composed of roles, and separate players running role processes from the roles. When an application is running, it binds a role with a player, and the player runs dynamically assigned role processes provided by an application for supporting adaptability. However, there has not been much attention on researches about development and runtime environment for role-based distributed systems. In this paper we suggest an application framework as an environment for developing and executing role-base distributed systems. The application framework is divided into two parts: an organization framework to manage and construct an organization composed of roles necessary in the application, and a player framework to provide running environment for players. In this paper, we focus on the organization framework which supports the creation and management of organizations, directory service for players and allocation of players to roles, and message brokering between roles and players. The proposed framework makes developers to be able to develop highly adaptive distributed systems in the ubiquitous environment.

• Journal of the Korea Society of Computer and Information
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• v.3 no.4
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• pp.110-119
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• 1998

This paper describes a C-API (Cryptographic-Application program Interface) mechanism that can serve cryptographic service to one or more application programmers in an open distributed computing system. Generic cryptographic service, provides application Programmers with cryptographic algorithms and interfaces which can be shared so that the programmers can program distributed applications containing security services even though they have no detailed knowledge of cryptographic algorithms. Therefore, in this paper, a generic C-API mechanism is designed that can be used independently from various application environments and basic system structures so that programmers can use it commonly. This mechanism has the advantage that allows application programmers be able to use some cryptographic services and key management services not considering of the application program and operating system.

• Journal of information and communication convergence engineering
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• v.8 no.5
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• pp.473-478
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• 2010

Today's engineering design is carried out in a distributed fashion geographically or physically. This places new requirements on the computational environments such as efficient integration and collaboration. With the advances of the Internet and Network environment recently, many researches have been proposed and at the same time, Web-based distributed design gives to a new paradigm in design and manufacturing fields. That is, Web-based technologies lead to reduce the product development times and to ensure a competitive product in order to exchange and interact of real-time design information that integrates the distributed design environment between departments as well as companies via Internet and Web. So, an efficient data communication for design information sharing is the foundation for collaborative systems in the distributed environment. Design data communication techniques such as CORBA, DCOM and RMI have been considered in the existing research but they have some problems that are limitations of interoperability and firewall problems in the Web. Therefore, this paper presents a Web-based distributed design application where distributed design information resources are integrated and exchanged using Web Services for supporting XML and HTTP without the interoperability and firewall problems through the 330K VLCC case.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.9
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• pp.82-92
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• 1998

An international standard for the product model data, STEP, and a standard for the distributed object technology, CORBA, will play a very important role in the future manufacturing environment. These two technologies provide background for the sharing of product data and the integration of applications on the network. This paper describes a prototype CAD/CAE environment that is integrated on the network by STEP and CORBA. Several application servers and client software were developed to verify the proposed concept. The present CAD/CAE environments are composed of several individual software components which are not tightly integrated. They also do not utilize the rapidly expanding network and object technologies for the collaboration in the product design process. In the design process in a large organization, sharing of application resources, design data and analysis data through the network will greatly enhance the productivity. The integration between applications can be supported by two key technologies, CORBA(Common Object Request Broker Architecture) and STEP(Standard for the Exchange of Product Model Bata). The CORBA provides interoperability between applications on different machines in heterogeneous distributed environments and seamlessly interconnects distributed object systems. Moreover, if all the data in the CAD/CAE environment are based on the STEP, then we can exclude all the data conversion problems between the application systems.

• The Journal of Information Technology
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• v.9 no.4
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• pp.25-34
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• 2006

As most application programs are more sophisticated and are adopted the distributed object technology, the object based distributed design became widespread since it supports portability and reusability. The approaches for fault-tolerant distributed computing are categorized into the active replica mechanism for mission-critical application programs and the passive replica mechanism for non mission-critical ones, when fault-tolerant facilities are added on. Our paper introduces the pros and drawbacks of several approaches for the add-on low-overhead fault-tolerant services by the surveys and shows the results of experiments for bench-mark models in order to demonstrate their performance.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.2
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• pp.37-45
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• 1999

CORBA IDL and RMI, the representative of distributed object model, support different approaches for distributed computing environments. CORBA approach does not support the application generated by RMI, even though it supports multiple programming languages. Object translation system between RMI to CORBA is designed and implemented for interoperability of distributed objects on the two different distributed programming environments. Suggested system is considered binding, inheritance, polymorphism, object passing, and callback which are key properties on the distributed objects. To validate the usefulness of the proposed system, we adopt a model for distrubuted objects and implement it as an application on the RMI environment. And, we translated it to an application on the CORBA environment. We observed the performance of translated application in the respect of inheritance, object passing, polymorphism across the machine boundary. Experiments showed that performance of distributed objects, those generated by translation system and those implemented on the CORBA environment, is equivalent.

• The Journal of the Korea Contents Association
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• v.8 no.4
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• pp.10-16
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• 2008

Quantity of encrypted data that transmitted through the network are increasing by development of encipherment technology. We have many problems; it is caused by technical development and service increase of user requests. It is necessary that create a many encryption key in one web application system. As a result, service quality comes to be low because of increased network traffic and system overload. There must be a system. That should be improved in secure service quality to process data. This paper describes a new approach for design and implementation of distributed encryption key processing for web application system. In this paper, it is based on distributed encipherment key, for the purpose of confidentially, integrity and authentication. It can prevent system degradation from server's data bottleneck and can improve service quality. For distributed encipherment system, we use java object activation technology. It can service while some distributed server are fail.

• International Journal of CAD/CAM
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• v.3 no.1_2
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• pp.51-60
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• 2003

The growth of the World Wide Web and the advances in high-speed network access have greatly changed existing CAD/CAE environment. The WWW has enabled us to share various distributed product data and to collaborate in the design process. An international standard for the product model data, STEP, and a standard for the distributed object technology, CORBA, are very important technological components for the interoperability in the advanced design and manufacturing environment. These two technologies provide background for the sharing of product data and the integration of applications on the network. This paper describes a distributed CAD/CAE environment that is integrated on the network by CORBA and product model data standard STEP. Several prototype application modules were implemented to verify the proposed concept and the test result is discussed. Finite element analysis server are further distributed into several frontal servers for the implementation of distributed parallel solution of finite element system equations. Distributed computation of analysis server is also implemented by using CORBA for the generalization of the proposed method.

• Journal of the Korea Society for Simulation
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• v.18 no.1
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• pp.35-40
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• 2009

The reliability of processing the distributed application becomes more and more important issues in distributed network as the usage of distributed network increases. Because the distributed network applications are processed in the available resources of Internet. It is important factors that the user can efficiently access the available resources and processed results can be delivered to the user of job request. Therefore in this paper, we suggested the survivability factor for sending data safely whether it can be efficiently accessed between the user and available resource which processes the distributed application. And evaluated the performance of the suggested factor using the data transmission time. Also we suggested the transmission algorithm for safe transmission using the survivability factor.