In this paper, we have shown a major element occupying the large portion of software communications architecture (SCA)-based software defined radio (SDR) handheld embedded system and an important feature for implementing a high speed broadband radio to an SCA waveform through a couple of experiments. First, this paper identifies the main items possessing the large portion of SCA-based SDR handheld embedded system by the experiment on the target platform which is similar to a commercial mobile handheld system. Both the world interoperabillity for microwave access (WiMAX) and high speed downlink packet access (HSDPA) waveform software packages are used as an SCA waveform application. This paper also presents the results of the relative binary size distribution of SCA software resources for looking for the major elements making an SCA-based SDR handheld embedded system heavier. As a result, when focusing on the relative weight portion of SCA core framework (CF), the SCA CF takes 16% up and others have 84% out of the whole binary size distribution of SCA software resources. The results of the experiment give us notice that the weight portion of SCA CF is minor and compatible with the overall software binary size needs of an SCA-based SDR handheld embedded system, on the other hand, the practical problem on the lightweight is in a common object request broker architecture (CORBA) and extensible markup language (XML) parser resources. Second, this paper describes an important feature for implementing a high speed broadband radio to an SCA waveform and presents the performance evaluation results of the SCA port communication on both power PC (PPC) 405 and x86 processor platforms. The PPC 405 platform, which is similar to a commercial mobile handset, takes the value of average round trip time (RTT) with a maximum of thirty six millisecond. The x86 platform, however, which is analogous to a server platform, maintains stable micro-second resolution. From our experiments, we observe that rapid SCA port communication, sufficiently less than the frame length of high-speed broadband radios, should be provided for serving those radio services in a commercial handheld system based on the SCA.

Data accessed by many sites are replicated in distributed environments for performance and availability. In this paper, replication schemes are examined in parallel image convolution processing. This paper presents a system architecture that we have developed with CORBA (Common Object Request Broker Architecture) for the processing. Employing CORBA enables us to make use of a cluster of workstations, each of which has a different level of computing power. The paper also describes a parallel and distributed image convolution processing model using replicas stored in a network of workstations, and reports some experimental results showing that our analytical model can agree with practical situations.

Active replication is a common approach to building highly available and reliable distributed software applications. The redundant nested invocation (RNI) problem arises when servers in a replicated group issues nested invocations to other server groups in response to a client invocation. Automatic suppression of RNI is always a desirable solution, yet it is usually a difficult design issue. If the system has multithreading support, the difficulties of implementation increase dramatically. Intuitively, to design a deterministic thread execution control mechanism is a possible approach. Unfortunately, some modern operating systems implement thread on kernel level for execution fairness. For the kernel thread case, modification on thread control implies modifying the operating system kernel. This approach loses system portability which is one of the important requirements of CORBA or middleware. In this work, we propose a mechanism to perform the auto-suppression of redundant nested invocation in an active replication fault-tolerant (FT) CORBA system. Besides the mechanism design, we discuss the design correctness semantic and the correctness proof of our design.

In this paper we describe collaborative constraint functional logic programming and the system called Open CFLP that supports this programming paradigm. The system solves equations by collaboration of various equational constraint solvers. The solvers include higher-order lazy narrowing calculi that serve as the interpreter of higher-order functional logic programming, and specialized solvers for solving equations over specific domains, such as a polynomial solver and a differential equation solver. The constraint solvers are distributed in an open environment such as the Internet. They act as providers of constraint solving services. The collaboration between solvers is programmed in a coordination language embedded in a host language. In Open CFLP the user can solve equations in a higher-order functional logic programming style and yet exploit solving resources in the Internet without giving low-level programs of distributions of resources or specifying details of solvers deployed in the Internet.

In distributed systems, the provision for failure-recovery is always a hot design issue, whereas no fault-tolerant feature has been extensively considered in the current RMI, CORBA and other OODP environments. As a result, application developers have to implement their own fault tolerant mechanisms. In this paper, we propose a fault-tolerant development environment based on one kind of RMI, called FT_HORB, as a Java extension for the reliable distributed computing with checkpoints and rollback-recovery mechanism. The FT_HORB is implemented on the Sun Ultra10 workstations connected through a 100 Mbps network. We observe that experimental applications on the FT_HORB can continue their operations in spite of hardware and software failures. Three benchmark models such as the nqueens problem, the traveling salesman problem and the gaussian elimination problem are experimented with the FT_HORB to evaluate its performance. The results show the performance of FT_HORB is acceptable. In addition, experiments demonstrate its possibility of extension to fully support our optimal design goal.

In order to realize universal service access of mobile users on the global telecommunication environment, we have to consider the scalable networking architecute based on the distributed object computing technologies. In this paper, we apply TINA to the promising networking architecture, and propose TINA-based scalable model for realizing personal mobility service, which especially focuses on making access to telecommunication services from any legacy systems that do not support such the new environment, using a downloadable module in an end terminal, as well as considering load balance of a whole system. Our proposed model also focuses on exchanging personal infomation of mobile users between different administrative domains, by separating the already-specified user profile information objects into two parts, which are the domain-common part and domain-specific part, and propose secure exchange procedure.

The Mobile Agent technology helps in the development of applications in open, distributed and heterogeneous environments such as the Internet and the Web, but it has to answer to the requirements of security and interoperability to achieve wide acceptance. The paper focuses on security and interoperability, and describes a Secure and Open Mobile Agent (SOMA) programming environment where both requirements are main design objectives. On the one hand, SOMA is based on a thorough security model and provides a wide range of mechanisms and tools to build and enforce flexible security policies. On the other hand, the SOMA framework permits to interoperate with different application components designed with different programming styles. SOMA grants interoperability by closely considering compliance with the OMG CORBA and MASIF standards. SOMA has already shown the feasibility and effectiveness of the approach for the development of flexible and adaptive applications in several areas, particularly in network and systems management.

Standard client-server workflow management systems have an intrinsic scalability limitation, the central server, which represents a bottleneck for large-scale applications. This server is also a single failure point that may disable the whole system. We propose a fully distributed architecture for workflow management systems. It is based on the idea that the case (an instance of the process) migrates from host to host, following a process plan, while the case activities are executed. This basic architecture is improved so that other requirements for Workflow Management Systems, besides scalability, are also contemplated. A CORBA-based implementation of such architecture is discussed, with its limitations, advantages and project decisions described.

TINA (Telecommunications Information Networking Architecture) has been developed to support efficient operation of a wide range of complex services. TINA is effective in building advanced multimedia related services and provides effective solutions for complex service control and management along with a high level of quality of services. However the benefits and effectiveness of TINA for other types of services such as ordinary telephone services and facsimile messaging services are not clear. This paper clarifies how to apply TINA to control and management of computer telephony (CT) services and ordinary telephony services. We designed and implemented CT services in a distributed processing environment (DPE), and in particular a click-to-dial service, as a target for our study. We demonstrate the effectiveness of the design through qualitative and quantitative evaluation. The results of our study show that the distributed processing technique, based on component concepts makes it easy to build and extend CT services, and also that TINA service architecture is applicable to ordinary telephony and advanced CT services.

Multimedia service users can require multi-services according to their own environment for accessing to public networks. For copying with customer-oriented service requirements, network providers have to prepare multi-layer service networks. This paper deals with frame relay, ATM and IP networking services on multi-layer networks. In order to provide multiple data services, network provider needs to define and make use of client-server and interworking relationships between these networks. In this paper, we propose a service management architecture in order to efficiently manage multiple services and network resources from service point of view. The proposed service management architecture includes functionalities such as subscription management, customer-network management, communication session management, and business layer support management. Especially, it describes an information model for managing multi-layer networks by way of the interworking or client-server relationship. The proposed functionalities are modeled in accordance with the object-oriented modeling concept and implemented on a CORBA platform. The applications on the proposed architecture include VPN services and various statistical services for customers and the carrier. The realized system is to be used for Koera Telecom's high speed networks mainly for supporting Internet services.

We have developed an active Q adaptor (AQA) to achieve integration of multiple management protocols and dynamic modification of managed object (MO) definitions. To achieve dynamic modification, we introduce a new MO framework, called dynamic-MO, which has the ability of modifying its own definition. A dynamic-MO is composed of meta-data and some behavior programs. Meta-data lists attributes of a dynamic-MO in a text format and a behavior program describes actions of a dynamic-MO in scripting language such as Java, Tcl, etc. In our AQA architecture, modules which manage individual components of a dynamic-MO communicate among themselves via an object request broker (ORB) in order to achieve system scalability with high performance. To realize the functionality of a dynamic-MO, we propose interfaces among these modules that are independent of dynamic-MO definitions and an update mechanism of behavior programs. We define the interfaces based on the common management information protocol (CMIP) operations to avoid re-defining the interfaces when dynamic-MO definitions are modified. Furthermore, to execute modified behavior programs without any negative influence on the workings of the other behavior programs, we employ a Java class-loader which has its own specific naming-space on a Java virtual machine (Java VM). With all of these features, our AQA is extremely promising for developing programmable network management systems for end-to-end management of heterogeneous telecommunication networks.

Today's complicated and heterogeneous telecommunication network environments need fully-integrated, cost-effective, user-friendly management systems. When developing such management systems in distributed environments, many telecommunication companies are carefully adopting CORBA and Java technologies. CORBA technology enables developers to create and manipulate distributed management system components easily while Java technology liberates human users from complicated and proprietary management system interfaces. In this paper, we propose a TMN-based integration framework for distributed network management by combining both CORBA and Java technologies. The framework generalizes a logically-layered architecture from the management agents layer to the user interface layer. It also provides generalized TMN management interfaces using inter-domain gateway systems for coordinating heterogeneous management protocols. By using these interfaces, TMN management function components can be easily constructed as CORBA objects to provide powerful TMN management services to administrators via user-friendly Web browsers. On the basis of this framework, we have designed and implemented a TMN alarm surveillance system which realizes our framework.

This paper proposes an implementation of the Telecommunications Information Networking Architecture (TINA) connection management system, based on our involvement of The TINA Trial (TTT). The system is used for managing ATM networks, which consist of network elements with SNMP interfaces. It provides setup, configuration, and release of ATM connection with a GUI-based network design tool that generates network resource data used for deploying TINA software components. This paper reports on a method of implementing TINA components over a Distributed Processing Environment (DPE) and an effective way to manage computational objects with multiple interfaces by using the Trading Service.

In this paper, we design and implement a Web-based Internet/Intranet service management system which can support Quality of Service (QoS) contracted by users and service providers, using Service Level Agreement (SLA) concept. We have analyzed the requirements and management information for Internet/Intranet service management. Based on this analysis, we have defined the suitable QoS parameters for the management of Internet/Intranet services, and developed new WWW service Management Information Bases (MIBs) for QoS management by extending the existing IETF's MIBs. The support of QoS management is done by incorporating the SLA concept, which is measured, monitored and controlled systematically in a multi-domain environment. Finally, we have built a prototype system, and evaluated its performance. The prototype system utilizes Java and CORBA technologies, so that various benefits of these technologies such as platform independence and scalability can be obtained.

Up to now, a lot of efforts have been made for the management of telecommunication networks and equipment, but less effort has been made for the realization of higher-layer service and business management. Common Object Request Broker Architecture (CORBA) provides the infrastructure for interoperability of various object-oriented management applications in a distributed environment, and being widely used to develop distributed systems in many areas of information processing technologies. There are recently worldwide growing interests for applying CORBA technology for the realization of higher layer Telecommunication Management Network (TMN) management functions. In this paper, we propose a platform architecture for the efficient integration of CORBA technology within TMN framework, where CORBA-based management functions as well as TMN-based management functions can be realized efficiently. GDMO/ASN. 1 to IDL translator has been designed and implemented for translating TMN management information into OMG CORBA IDL interface. The CORBA/CMIP gateway has also been designed for realization of the interaction translation specification of JIDM task force with some additional extensions. Finally, we evaluate the performance of the CORBA-based network management system, and analyze the code reusability for the construction of the CORBA-based management system, in order to show the efficiency of the architecture.

The OMG have made the trading service one of the basic CORBA services. A specification has been drawn up (OMG RPF5) but seems to have some problems in terms of scalability and complexity. This paper introduces an architecture called Contextual Clustering Using Service Properties (CCUSP) that deals with issues of scalability. It uses a contextual approach to clustering object service offers based on property commonalities. It also handles issues of scalability of trader federation. An ontological approach is to be used, however not covered in this paper. An implementation of the specialisation graph context model is detailed.

A major topic in the field of network and telecommunications is doing business on the World Wide Web (WWW), which is called Electronic Commerce (EC). Another major topic is blending Artificial Intelligence (AL) techniques with the WWW. In the Ex-W-Pert Project we have proposed an agent model for EC components that blends the traditional expert systems' reasoning engine with a multi-layer knowledge base, communication and documentation engines. In this project, EC is viewed as a society of software agents, such as customer, search, catalog, manufacturer, dealer, delivery and banker agents, interacting and negotiating with each other. Each agent has a knowledge-base and a reasoning engine, a communication engine and a documentation engine. The knowledge-base is organized in three layers: skill layer, rule layer and knowledge layer (S-R-K layers). In this project, for each EC agent, we identify the class of problems to be solved and build the knowledge base gradually for each layer. We believe that using this multi-layer knowledge base system will speed up the reasoning and ultimately reduce the operation costs.

As enterprises use ATM networks for their private networks and as these private networks use public ATM networks for wide area communication, the need for the customers to be able to manage both private and public networks is increasing. Currently, some standardization work is being done towards providing this capability to customers. In this paper, we propose a new customer network management (CNM) system architecture for the management of both private and public ATM networks in a uniform way. The particular features of the proposed architecture lies in the efficient support of the complex hierarchical TMN manager-agent relationships at M3 and M4 interfaces, and the support of SNMP and CMIP integration. The TMN hierarchical many-to-many manager-agent relationships are realized by the utilization of a CORBA-based Shared Management Knowledge (SMK) system. We have implemented a prototype of ATM CNM system, and measured the performance for the demonstration of the suitability of the proposed architecture.