Computing infrastructure issues in distributed communications systems : a survey of operating system transport system architectures

The performance of distributed applications (such as file transfer, remote login, tele-conferencing, full-motion video, and scientific visualization) is influenced by several factors that interact in complex ways. In particular, application performance is significantly affected both by communication infrastructure factors and computing infrastructure factors. Several communication infrastructure factors include channel speed, bit-error rate, and congestion at intermediate switching nodes. Computing infrastructure factors include (among other things) both protocol processing activities (such as connection management, flow control, error detection, and retransmission) and general operating system factors (such as memory latency, CPU speed, interrupt and context switching overhead, process architecture, and message buffering). Due to a several orders of magnitude increase in network channel speed and an increase in application diversity, performance bottlenecks are shifting from the network factors to the transport system factors.This paper defines an abstraction called an "Operating System Transport System Architecture" (OSTSA) that is used to classify the major components and services in the computing infrastructure. End-to-end network protocols such as TCP, TP4, VMTP, XTP, and Delta-t typically run on general-purpose computers, where they utilize various operating system resources such as processors, virtual memory, and network controllers. The OSTSA provides services that integrate these resources to support distributed applications running on local and wide area networks.A taxonomy is presented to evaluate OSTSAs in terms of their support for protocol processing activities. We use this taxonomy to compare and contrast five general-purpose commercial and experimental operating systems including System V UNIX, BSD UNIX, the x-kernel, Choices, and Xinu

Enterprise application reuse: Semantic discovery of business grid services

Web services have emerged as a prominent paradigm for the development of distributed software systems as they provide the potential for software to be modularized in a way that functionality can be described, discovered and deployed in a platform independent manner over a network (e.g., intranets, extranets and the Internet). This paper examines an extension of this paradigm to encompass ‘Grid Services’, which enables software capabilities to be recast with an operational focus and support a heterogeneous mix of business software and data, termed a Business Grid - "the grid of semantic services". The current industrial representation of services is predominantly syntactic however, lacking the fundamental semantic underpinnings required to fulfill the goals of any semantically-oriented Grid. Consequently, the use of semantic technology in support of business software heterogeneity is investigated as a likely tool to support a diverse and distributed software inventory and user. Service discovery architecture is therefore developed that is (a) distributed in form, (2) supports distributed service knowledge and (3) automatically extends service knowledge (as greater descriptive precision is inferred from the operating application system). This discovery engine is used to execute several real-word scenarios in order to develop and test a framework for engineering such grid service knowledge. The examples presented comprise software components taken from a group of Investment Banking systems. Resulting from the research is a framework for engineering servic

Performance Evaluation and Comparison of CORBA Implementations for the Java Platform

Middleware is a software layer between the applications, services and the operating system that provides an abstraction to the application programmer. It masks the heterogeneous nature of the network and provides such services as remote calls, naming service, transaction process abilities, and security services. Common Object Request Broker Architecture (CORBA) is a middleware design that is implemented through the use of Object Request Broker (ORB), which is a software component that,allows communication between the remote objects and applications that use them in a distributed environment. CORBA applications can run on almost any platform, operating system, and support different languages. There are many types of distributed object middleware on the market such as Sun\u27s Java 2 ORB, Inprises\u27s VisiBroker for Java, IONA\u27s ORBacus for Java, and IONA\u27s Orbix 2000 for Java. Because of these various products, it is difficult to select the product that will provide the specific requirements for one\u27s application. The goal of this project is to evaluate the above-mentioned implementations of the CORBA standards and, additionally, CORBA was compared to LAMIMPI for efficiency. The results of this project should provide developers and novices studying distributed systems the necessary data to evaluate and select the most efficient CORBA product to meet their specific design requirements, and provide a methodology for further evaluation

Dynamic Context Awareness of Universal Middleware based for IoT SNMP Service Platform

This study focused on the Universal Middleware design for the IoT (Internet of Things) service gateway for the implementation module of the convergence platform. Recently, IoT service gateway including convergence platform could be supported on dynamic module system that is required mounting and recognized intelligent status with the remote network protocol. These awareness concepts support the dynamic environment of the cross-platform distributed computing technology is supported by these idea as a Universal Middleware for network substitution. Distribution system commonly used in recent embedded systems include CORBA (Common Object Request Broker Architecture), RMI (Remote Method Invocation), DCE (Distributed Computing Environment) for dynamic service interface, and suggested implementations of a device object context. However, the aforementioned technologies do not support each standardization of application services, communication protocols, and data, but are also limited in supporting inter-system scalability. In particular, in order to configure an IoT service module, the system can be simplified, and an independent service module can be configured as long as it can support the standardization of modules based on hardware and software components. This paper proposed a design method for Universal Middleware that, by providing IoT modules and service gateways with scalability for configuring operating system configuration, may be utilized as an alternative. This design could be a standardized interface provisioning way for hardware and software components as convergence services, and providing a framework for system construction. Universal Middleware Framework could be presented and dynamic environment standardization module of network protocols, various application service modules such as JINI (Apache River), UPnP (Universal Plug & Play), SLP (Service Location Protocol) bundles that provide communication facilities, and persistence data module. In this IoT gateway, management for based Universal Middleware framework support and available for each management operation, application service component could be cross-executed over SNMP (Simple Network Management Protocol) version 1, version 2, and version 3. The way of SNMP extension service modules are conducted cross-support each module and independent system meta-information that could be built life cycle management component through the MIB (Management Information Base) information unit analysis. Therefore, the MIB role of relation with the Dispatcher applied to support multiple concurrent SNMP messages by receiving incoming messages and managing the transfer of PDU (Protocol Data Unit) between the RFC 1906 network in this study. Results of the study revealed utilizing Universal Middleware that dynamic situations of context objects with mechanisms and tools to publish information could be consisted of IoT to standardize module interfaces to external service clients as a convergence between hardware and software platforms

The Design of a System Architecture for Mobile Multimedia Computers

This chapter discusses the system architecture of a portable computer, called Mobile Digital Companion, which provides support for handling multimedia applications energy efficiently. Because battery life is limited and battery weight is an important factor for the size and the weight of the Mobile Digital Companion, energy management plays a crucial role in the architecture. As the Companion must remain usable in a variety of environments, it has to be flexible and adaptable to various operating conditions. The Mobile Digital Companion has an unconventional architecture that saves energy by using system decomposition at different levels of the architecture and exploits locality of reference with dedicated, optimised modules. The approach is based on dedicated functionality and the extensive use of energy reduction techniques at all levels of system design. The system has an architecture with a general-purpose processor accompanied by a set of heterogeneous autonomous programmable modules, each providing an energy efficient implementation of dedicated tasks. A reconfigurable internal communication network switch exploits locality of reference and eliminates wasteful data copies

The design and implementation of a multimedia storage server tosupport video-on-demand applications

In this paper we present the design and implementation of a client/server based multimedia architecture for supporting video-on-demand applications. We describe in detail the software architecture of the implementation along with the adopted buffering mechanism. The proposed multithreaded architecture obtains, on one hand, a high degree of parallelism at the server side, allowing both the disk controller and the network card controller work in parallel. On the other hand; at the client side, it achieves the synchronized playback of the video stream at its precise rate, decoupling this process from the reception of data through the network. Additionally, we have derived, under an engineering perspective, some services that a real-time operating system should offer to satisfy the requirements found in video-on-demand applications.This research has been supported by the Regional Research Plan of the Autonomus Community of Madrid under an F.P.I. research grant.Publicad