Middleware: a model for distributed system services
TL;DR: Today’s enterprise computing facilities are only an approximation of the vision of an information utility, and some businesses are redefining their business processes to use the utility to bridge formerly isolated component activities.
Abstract: he computing facilities of largescale enterprises are evolving into a utility, much like power and telecommunications. In the vision of an information utility, each knowledge worker has a desktop appliance that connects to the utility. The desktop appliance is a computer or computer-like device, such as a terminal, personal computer, workstation, word processor, or stock trader’s station. The utility itself is an enterprise-wide network of information services, including applications and databases, on the localarea and wide-area networks. Servers on the local-area network (LAN) typically support files and file-based applications, such as electronic mail, bulletin boards, document preparation, and printing. Local-area servers also support a directory service, to help a desktop user find other users and find and connect to services of interest. Servers on the wide-area network (WAN) typically support access to databases, such as corporate directories and electronic libraries, or transaction processing applications, such as purchasing, billing, and inventory control. Some servers are gateways to services offered outside the enterprise, such as travel or information retrieval services, news feeds (e.g., weather, stock prices), and electronic document interchange with business partners. In response to such connectivity, some businesses are redefining their business processes to use the utility to bridge formerly isolated component activities. In the long term, the utility should provide the information that people need when, where, and how they need it. Today’s enterprise computing facilities are only an approximation of the vision of an information utility. Most organizations have a wide variety of heterogeneous hardware systems, including personal computers, workstations, minicomputers, and mainframes. These systems run different operating systems (OSs) and rely on different network architectures. As a result, integration is difficult and its achievement uneven. For example, local-area servers are often isolated from the WAN. An appliance can access files and printers on its local server, but often not those on the servers of other LANs. Sometimes an application available on one local area server is not available on other servers, because other departments use servers
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Book•
01 Apr 2007
TL;DR: This paper describes the development of Wireless Sensors Networks and its applications, and some of the applications can be found in the Commercial and Scientific Applications of Wireless Sensor Networks and Performance and Traffic Management Issues.
Abstract: Chapter 1. Introduction and Overview of Wireless Sensor Networks. Chapter 2. Commercial and Scientific Applications of Wireless Sensor Networks. Chapter 3. Basic Wireless Sensor Technology. Chapter 4. Wireless Sensors Networks Protocols: Physical Layer. Chapter 5. Medium Access Control Protocols for Wireless Sensor Networks. Chapter 6. Sensors Network Protocols: Routing Protocols. Chapter 7. Transport Control Protocols for Wireless Sensors Networks. Chapter 8. Middleware for Sensor Networks. Chapter 9. Network Management for Wireless Sensor Networks. Chapter 10. Operating Systems for Sensor Networks. Chapter 11. Performance and Traffic Management Issues. Appendix A: Analysis. Appendix B: Discussions. Index.
1,088 citations
01 Jan 2002
TL;DR: This survey reviews the field of P2P systems and applications by summarizing the key concepts and giving an overview of the most important systems, and is intended for users, developers, and information technologies maintaining systems.
Abstract: The term “peer-to-peer” (P2P) refers to a class of systems and applications that employ distributed resources to perform a critical function in a decentralized manner. With the pervasive deployment of computers, P2P is increasingly receiving attention in research, product development, and investment circles. This interest ranges from enthusiasm, through hype, to disbelief in its potential. Some of the benefits of a P2P approach include: improving scalability by avoiding dependency on centralized points; eliminating the need for costly infrastructure by enabling direct communication among clients; and enabling resource aggregation. This survey reviews the field of P2P systems and applications by summarizing the key concepts and giving an overview of the most important systems. Design and implementation issues of P2P systems are analyzed in general, and then revisited for each of the case studies described in Section 6. This survey will help people understand the potential benefits of P2P in the research community and industry. For people unfamiliar with the field it provides a general overview, as well as detailed case studies. It is also intended for users, developers, and information technologies maintaining systems, in particular comparison of P2P solutions with alternative architectures and
819 citations
Cites background or methods from "Middleware: a model for distributed..."
...…etc.), distributed file servers (NFS [Sandberg et al. 1985], AFS [Howard et al. 1988], CORBA Object Request Brokers [OMG 1996], HTTP Server, authentication server, etc. Client-server model examples include CORBA, RMI [Wollrath et al 1996], and other middleware [Bernstein 1996; Britton 2000])....
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...Client-server model examples include CORBA, RMI [Wollrath et al 1996], and other middleware [Bernstein 1996; Britton 2000])....
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TL;DR: In this article, the authors present a survey of the field of process migration by summarizing the key concepts and giving an overview of the most important implementations, including MOSIX, Sprite, Mach, and Load Sharing Facility.
Abstract: Process migration is the act of transferring a process between two machines. It enables dynamic load distribution, fault resilience, eased system administration, and data access locality. Despite these goals and ongoing research efforts, migration has not achieved widespread use. With the increasing deployment of distributed systems in general, and distributed operating systems in particular, process migration is again receiving more attention in both research and product development. As high-performance facilities shift from supercomputers to networks of workstations, and with the ever-increasing role of the World Wide Web, we expect migration to play a more important role and eventually to be widely adopted.This survey reviews the field of process migration by summarizing the key concepts and giving an overview of the most important implementations. Design and implementation issues of process migration are analyzed in general, and then revisited for each of the case studies described: MOSIX, Sprite, Mach, and Load Sharing Facility. The benefits and drawbacks of process migration depend on the details of implementation and, therefore, this paper focuses on practical matters. This survey will help in understanding the potentials of process migration and why it has not caught on.
551 citations
Proceedings Article•
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01 May 1999
TL;DR: This survey reviews the field of process migration by summarizing the key concepts and giving an overview of the most important implementations, and then revisited for each of the case studies described.
Abstract: Process migration is the act of transferring a process between two machines. It enables dynamic load distribution, fault resilience, eased system administration, and data access locality. Despite these goals and ongoing research efforts, migration has not achieved widespread use. With the increasing deployment of distributed systems in general, and distributed operating systems in particular, process migration is again receiving more attention in both research and product development. As high-performance facilities shift from supercomputers to networks of workstations, and with the ever-increasing role of the World Wide Web, we expect migration to play a more important role and eventually to be widely adopted.
This survey reviews the field of process migration by summarizing the key concepts and giving an overview of the most important implementations. Design and implementation issues of process migration are analyzed in general, and then revisited for each of the case studies described: MOSIX, Sprite, Mach, and Load Sharing Facility. The benefits and drawbacks of process migration depend on the details of implementation and, therefore, this paper focuses on practical matters. This survey will help in understanding the potentials of process migration and why it has not caught on.
503 citations
Cites background from "Middleware: a model for distributed..."
...Because of the increasing costs of operating system development and the lack of standard solutions for distributed systems and heterogeneity, middleware level solutions have become of more interest [Bernstein, 1996]....
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...Innovations in OS services take place at the middleware level rather than in kernels [Bernstein, 1996]....
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...Innovations in OS services take place at the middleware level rather than in kernels [Bernstein, 1996]....
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...Because of the increasing costs of operating system development and the lack of standard solutions for distributed systems and heterogeneity, middleware level solutions have become of more interest [Bernstein, 1996]....
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TL;DR: Reconfigurable Context-Sensitive Middleware facilitates the development and runtime operations of context-sensitive pervasive computing software.
Abstract: Context-sensitive applications need data from sensors, devices, and user actions, and might need ad hoc communication support to dynamically discover new devices and engage in spontaneous information exchange. Reconfigurable Context-Sensitive Middleware facilitates the development and runtime operations of context-sensitive pervasive computing software.
416 citations
References
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Book•
01 Feb 1987TL;DR: In this article, the design and implementation of concurrency control and recovery mechanisms for transaction management in centralized and distributed database systems is described. But this can lead to interference between queries and updates.
Abstract: This book is an introduction to the design and implementation of concurrency control and recovery mechanisms for transaction management in centralized and distributed database systems. Concurrency control and recovery have become increasingly important as businesses rely more and more heavily on their on-line data processing activities. For high performance, the system must maximize concurrency by multiprogramming transactions. But this can lead to interference between queries and updates, which concurrency control mechanisms must avoid. In addition, a satisfactory recovery system is necessary to ensure that inevitable transaction and database system failures do not corrupt the database.
3,891 citations
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TL;DR: Data communications in Japan have begun a new era of rapid progress, and public-switched telephone and telex networks are available for data communications.
Abstract: T WO common carriers are operated under the administration of the Ministry of Posts and Telecommunications in Japan. One is NTT (Ni'ppon Telegraph & Telephone Public Corporation) for domestic services. The other is KDD (Kokusai Denshin Denwa Company, Ltd.) for overseas services. For the past year, NTT has had DDX (digital data exchange) circuitswitched data network and DDX packet-switched data network services, and KDD has commenced ICAS (international computer access service). Data communications in Japan have begun a new era of rapid progress. Their features are summarized as follows. 0 Both domestic and overseas telephone networks allow nonvoice communications as well as voice. Customers can connect their own terminals to the networks via Modems and NCU's. Public-switched telephone and telex networks are available for data communications. 0 Various speed class leased circuit service is provided.
98 citations
TL;DR: This article describes one efficient method for estimating gradients in the Monte Carlo setting, namely the likelihood ratio method (also known as the efficient score method), and derives likelihood-ratio-gradient estimators for both time-homogeneous and non-time homogeneous discrete-time Markov chains.
Abstract: A transaction processing (TP) application is a program that performs an administrative function by accessing a shared database on behalf of an on-line user. A TP system is an integrated set of products that supports TP applications. These products include both hardware, such as processors, memories, disks and communications controllers, and software such as operating systems (Oss), database management systems (DBMSs), computer networks and TP monitors. Much of the integration of these products is provided by TP monitors which coordinate the flow of transaction request between terminals that issue requests and TP applications that can process them.Today, TP represents over 25 percent of the computer systems market and is one of the growing segments of the computer business. TP applications appear in most sectors of large-scale enterprises such as airline reservation, electronic banking, securities trading, inventory and production control, communications switching, videotex, sales management, military command and control and government services.
73 citations
"Middleware: a model for distributed..." refers methods in this paper
...To illustrate middleware concepts, we will look at one type of framework: TP monitors [1]....
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