Limitation of Distributed system

Top Limitation of Distributed system A distributed system is a set of computers that communicate over a network, and do not share a common memory or a common clock Absence of a common (global) clock No concept of global time It’s difficult to reason about the temporal ordering of events Cooperation between processes (e.g., producer/consumer, … Read more

Agreement in Pepperland in distributed system

Two divisions of the Pepperland army, ‘Apple’ and ‘Orange’, are encamped at the top of two nearby hills. Further along the valley below are the invading Blue Meanies. The Pepperland divisions are safe as long as they remain in their encampments, and they can send out messengers reliably through the valley to communicate. The Pepperland … Read more

Fundamental Models in distributed system

Models of systems share some fundamental properties. In particular, all of them are composed of processes that communicate with one another by sending messages over a computer network. All of the models share the design requirements of achieving the performance and reliability characteristics of processes and networks and ensuring the security of the resources in … Read more

Architectural models in distributed system

The architecture of a system is its structure in terms of separately specified components and their interrelationships. The overall goal is to ensure that the structure will meet present and likely future demands on it. Major concerns are to make the system reliable, manageable, adaptable and cost-effective. The architectural design of a building has similar … Read more

Physical models in distributed system

A physical model is a representation of the underlying hardware elements of a distributed system that abstracts away from specific details of the computer and networking technologies employed Baseline physical model: A distributed system is one in which hardware or software components located at networked computers communicate and coordinate their actions only by passing messages. … Read more

Difficulties and threats for distributed systems

Here are some of the problems that the designers of distributed systems face Widely varying modes of use: The component parts of systems are subject to wide variations in workload – for example, some web pages are accessed several million times a day. Some parts of a system may be disconnected, or poorly connected some … Read more

The World Wide Web

The World Wide Web [ I, Berners-Lee 1991] is an evolving system for publishing and accessing resources and services across the Internet. Through commonly available web browsers, users retrieve and view documents of many types, listen to audio streams and view video streams, and interact with an unlimited set of services. The Web began life … Read more

Resource sharing and the Web Challenges

Users are so accustomed to the benefits of resource sharing that they may easily overlook their significance. We routinely share hardware resources such as printers, data resources such as files, and resources with more specific functionality such as search engines In practice, patterns of resource sharing vary widely in their scope and in how closely … Read more

Trends in distributed systems

Distributed systems are undergoing a period of significant change and this can be traced back to a number of influential trends: the emergence of pervasive networking technology; the emergence of ubiquitous computing coupled with the desire to support user mobility in distributed systems; the increasing demand for multimedia services; the view of distributed systems as … Read more

Examples of distributed systems

Distributed systems encompass many of the most significant technological developments of recent years and hence an understanding of the underlying technology is absolutely central to a knowledge of modern computing. The figure also provides an initial insight into the wide range of applications in use today, from relatively localized systems (as found, for example, in … Read more