Distributed System Presentation Chapter 1
- 1. From Coulouris, Dollimore, Kindberg and Blair Distributed Systems: Concepts and Design Edition 5, © Addison-Wesley 2012 Slides for Chapter 1 Characterization of Distributed Systems
- 2. 2 Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Distributed System •Distributed System: is a collection of autonomous computers linked by a computer network. •Distributed System software enables computers to coordinate their activities and share resources A distributed system is a collection of independent computers that work together as a single system.
- 3. 3 Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Characteristics • Resource Sharing: Resources such as memory, storage, and processing power can be shared across multiple machines • Concurrency: A distributed operating system allows multiple processes to execute simultaneously on different machines • Scalability: The system can easily be scaled up or down by adding or removing nodes, making it highly adaptable to changing demands. • Fault tolerance: Distributed operating systems are designed to continue functioning even in the event of node failures. Ensures reliability. • Transparency: The system makes it appear as if all resources are available locally, even though they may be located on a different machine. • Heterogeneity: Distributed operating systems can support a wide variety of hardware and software configurations across different machines. • Openness: how open is the software designed to be developed and shared with each other. MSP
- 4. 4 Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Figure 1.1 (see book for the full text) Selected application domains and associated networked applications Finance and commerce eCommerce e.g. Amazon and eBay, PayPal, online banking and trading The information society Web information and search engines, ebooks, Wikipedia; social networking: Facebook and MySpace. Creative industries and entertainment online gaming, music and film in the home, user- generated content, e.g. YouTube, Flickr Healthcare health informatics, on online patient records, monitoring patients Education e-learning, virtual learning environments; distance learning Transport and logistics GPS in route finding systems, map services: Google Maps, Google Earth Science The Grid as an enabling technology for collaboration between scientists Environmental management sensor technology to monitor earthquakes, floods or tsunamis
- 5. Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 intranet ISP desktop computer: backbone satellite link server: network link: Figure 1.3 A typical portion of the Internet
- 6. Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Figure 1.4 Portable and handheld devices in a distributed system
- 7. 7 Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Figure 1.5 Cloud computing
- 8. Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Figure 1.6 Growth of the Internet (computers and web servers) Date Computers Web servers Percentage 1993, July 1,776,000 130 0.008 1995, July 6,642,000 23,500 0.4 1997, July 19,540,000 1,203,096 6 1999, July 56,218,000 6,598,697 12 2001, July 125,888,197 31,299,592 25 42,298,371 2003, July 2005, July ~200,000,000 353,284,187 67,571,581 21 19
- 9. Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Section 1.5 Challenges • Heterogeneity:. • Openness : • Security : • Scalability : • Failure handling : • Concurrency : • Transparency : • Quality of service :
- 10. Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Section 1.5.7 Transparencies •Access transparency: enables local and remote resources to be accessed using identical operations. •Location transparency: enables resources to be accessed without knowledge of their physical or network location (for example, which building or IP address). •Concurrency transparency: enables several processes to operate concurrently using shared resources without interference between them. •Replication transparency: enables multiple instances of resources to be used to increase reliability and performance without knowledge of the replicas by users or application programmers. •Failure transparency: enables the concealment of faults, allowing users and application programs to complete their tasks despite the failure of hardware or software components. •Mobility transparency: allows the movement of resources and clients within a system without affecting the operation of users or programs. •Performance transparency: allows the system to be reconfigured to improve performance as loads vary. •Scaling transparency: allows the system and applications to expand in scale without change to the system structure or the application algorithms.
- 11. Instructor’s Guide for Coulouris, Dollimore, Kindberg and Blair, Distributed Systems: Concepts and Design Edn. 5 © Pearson Education 2012 Figure 1.7 Web servers and web browsers Internet Browsers Web servers www.google.com www.cdk5.net www.w3c.org standards faq.html http://www.w3.org/standards/faq.html#conformance http://www.google.comlsearch?q=obama http://www.cdk5.net/ File system of www.w3c.org