Distributed System • A possible definition: a distributed system is a system in which hardware or software components located at networked computers communicate and coordinate their actions only by passing messages. Distributed systems possesses the following characteristics; a) Resource Sharing The prime motivation for constructing and using distributed systems stems from a desire to share resources. o A distributed system is a collection of independent computers that appear to the users of the system as a single coherent system. What is a distributed system? Resource Sharing Resource: hardware - disks and printers software - files, windows, and data objects Hardware sharing for: convenience reduction of cost Key characteristics of distributed systems . A distributed system is a collection of independent computers appears to its users as a single and coherent system. Transparency refers to hiding details from a user. Resource sharing Openess Concurrency Scalability Fault Tolerance Transparency . i. The following types of transparency are desirable. Distributed File Systems. Concurrency of components ! ... Characteristics of Distributed system. Examples of Distributed Systems. Lack of a global ‘clock’ Such event feeds share the following characteristics. • Networked computers (i.e., computers that are connected by a network) may be spatially separated by any distance: Mandatory characteristics determine the basic nature of distributed systems, such as having multiple entities, heterogeneity, concurrency and resource sharing. This definition leads to the following characteristics of distributed systems: ! The term ‘resource’ is a rather abstract one, but it best characterizes the range of things that can usefully be shared in a networked computer system. A distributed system, also known as distributed computing, is a system with multiple components located on different machines that communicate and coordinate actions in order to appear as a single coherent system to the end-user. A collection of workstations and mainframes connected by a Local Area Network (LAN) is a configuration on Distributed File System. A good distributed file system should have the following features: 1. Transparency. Structure transparency: Multiple file servers are used to provide better performance, scalability, and reliability. The main purpose of the Distributed File System (DFS) is to allows users of physically distributed systems to share their data and resources by using a Common File System. Definition: A distributed system is one in which components located at networked computers communicate and coordinate their actions only by passing messages. Distributed operating system allows distributing of entire systems on the couples of center processors, and it serves on the multiple real time products as well as multiple users. CIS 505, Spring 2007 Distributed Systems 3 Examples The world wide web – information, resource sharing Clusters, Network of workstations Distributed manufacturing system (e.g., A distributed system in its most simplest definition is a group of computers working together as to appear as a single computer to the end-user. The goal of this section is to provide motivational examples of contemporary distributed systems and the great diversity of the associated applications. Multiple entities One of the key characteristics of a distributed system is the presence of multiple – in many cases a great many – entities participating in the system. To present a single-system image: Hide internal organization, communication details; Provide uniform interface; “Distributed Systems” can be characterized by following aspects: * Resource Sharing: Connecting Resources and Users. A distributed system is a system whose components are located on ... === I hope this article would help you for basic understating of key characteristics in a distributed system design patterns