1. Introduction II

1. 1. Introduction II Quiz due at 5 PM Tuesday, 26 August 2014

2. Distributed Systems Family Distributed Systems Distributed Computing Systems Distributed Embedded Systems Distributed Information Systems Transaction Processing Systems Home Systems Sensor Networks Clusters Office Databases Grids Electronic Healthcare Systems Ubiquitous Computing Environments

3. Cluster • Thousands of identical parallel processors have taken over traditional supercomputers’ big math. • Beowulf’s master allocates batch jobs among slaves. • MOSIX’ processes transparently travel from home node to others for resources, appearing to be a single system.

4. Grid • Disparate collaborating groups (“virtual organ-ization”), sharing their expensive resources. Middle -ware SOA

5. R U O K ? 1. Which of the following is an example of a distributed computing system? a. An information computing system. b. A cluster computing system. c. An embedded computing system. d. A grid computing system. e. Both b and d above.

6. R U O K ? 2. How do clusters and grids differ? a. The workstations in a grid are all the same; clusters’ can differ widely. b. Clusters unite collaborators into a virtual organization; grid users are in one company. c. Clusters have one administrator; grids are federated. d. Middleware connects cluster apps and resources; two networks connect them in a grid. e. The SOA and SGSA standards specify cluster architectures; grids are ad hoc.

7. R U O K ? 3. Beowulf… a. Is a grid computing system. b. Enables processes to transparently travel from their home nodes to other nodes for resources. c. Attempts to provide a single-system image. d. Consists of a master that allocates batch jobs among slave processors. e. All of the above.

8. R U O K ? Match the following grid layers with their definitions below: 4. Resource __ 5. Fabric __ 6. Applications__ 7. Collective __ 8. Connectivity __ a. Configures interfaces to local resources with a cross-point switch. b. Authenticates users’ apps and local resources, then communicates by protocols with resources. c. Provides hardware driver DLLs. d. Discovers needed resources and schedules their access. e. Contains the users’ applications.

9. R U O K ? 9. Which of the following is true? a. All grid layers at an administrative unit’s site are collectively called an open grid services architecture (OGSA). b. The service-oriented architecture (SOA) is a standard that specifies the OGSA, plus all of its component parts. c. All but the top and bottom layers of a grid computing system are called “middleware.” d. MOSIX is one example of a grid computing system. e. The three major types of distributed systems are distributed computing systems, distributed information systems and distributed real-time systems.

10. Distributed Information Systems • Distributed data base systems dominate traditional offices. • The enterprise application integration (EIA) industry standardizes multiple user’s multiple database service transactions. • Transaction processing systems move money securely in banks.

11. Transaction Processing Systems • Every uninterruptable, all-or-nothing transaction has a BEGIN and END. • A transaction starts with a private copy of its bank’s ledger, which it changes and writes back to the bank after it commits. • Transactions are ACID: • Atomic (indivisible) • Consistent (obeys banks’ Law of Conservation of Money) • Isolated (parallel tasks appear serial) • Durable (changes are permanent.

12. Transaction Processing Systems • Transactions also can be nested (fork & join), but sub-transactions are not durable. • Remote procedure calls (RPCs) direct distant servers to withdraw and direct money, send and receive mail, etc. • A transaction processing monitor (TPM) could handle three different airline reservation servers (above), for travelers planning a trip.

13. Enterprise Application Integration • Today’s transaction processing apps autonomously talk with each other (no TPM intervention) via… • middleware (above). • RPCs (remote procedure calls for apps). • RMIs (remote method invocations of objects). • Publish/subscribe message-oriented middleware (MOM) handles tightly coupled app communications, when the subscriber might not always be available.

14. R U O K ? 10. Automated banking transactions must be… a. Atomic; i.e., indivisible. b. Consistent; e.g., obedient to the Law of Conservation of Money. c. Isolated; i.e., parallel tasks appear to happen serially. d. Durable; i.e., changes are permanent. e. All of the above.

15. R U O K ? Match the following abbreviations with their definitions below: 11. EIA __ 12. TPM__ 13. RPC__ 14. RMI __ 15. MOM__ a. Publish/subscribe middleware. b. Execute distant servers’ apps. c. Standardizes many user’s multiple database service transactions. d. Execute distant servers’ methods. e. CoCoordinate transactions on many servers.

16. R U O K ? 16. Which of the following describe(s) a “transaction”? a. Contacts distant servers to withdraw and direct money, send and receive mail, etc. b. Uninterruptable, all-or-nothing. c. Its parts may not be durable. d. Makes private copy of bank ledger, changes it and replaces the original with it. e. All of the above.

17. R U O K ? 17. In the Enterprise Application Integration paradigm, transaction processing apps can talk with each other via middleware. a. True. b. False.

18. R U O K ? 18. Publish/subscribe middleware 1) accepts a message from any app at any time and 2) delivers an app’s designated messages whenever the app is available to receive them. a. True. b. False.

19. Distributed Pervasive Systems • WIFI laptops and mobile phones are designed to… • To adapt to new environments without administrator intervention • To embrace context changes; e.g., cell tower hand-offs • To enable user preferences • To share data freely

20. Home Systems • Universal plug-and play standards (e.g., Bluetooth) join… • personal computers • TVs • video games • security systems • personal wearable electronics • Centralizing stored data saves money on low-capacity cell phones. • Privacy concerns: • Can the FBI seize (4th Amendment rights) the personal data you store in the cloud? Yes, it is outside the home in a public place. • Privacy-concerned small towns are selling UAV Hunting Licenses. • “Recommenders” automatically organize your personal data like they see others doing it.

21. Electronic Healthcare Systems • Preventive care keeps people out of expensive hospitals. • A wireless body area network (BAN) may… • May autonomously gather data to periodically upload from its hub • May be controlled by a physician’s external network (above). • Design considerations: • Where to store data? • how to prevent its loss? • what alerts to generate? • when to intervene? • how reliable is it? • how secure is it?

22. Sensor Networks • Monitoring bridge safety, traffic, weather and volcanoes call for thousands of sensors organized as a distributed database (above). • They may accept queries or spontaneously deliver data at regular intervals or upon an event. • Aggregating data with TinyDB’s in-network data processing can dramatically reduce sensor tree-network traffic. • Publish/subscribe middleware may optimize data transfers among temporally and geographically dispersed sensors.

23. R U O K ? 20. Privacy concerns in distributed pervasive systems include: a. Amazon’s UAV (unpiloted air vehicle) possibly glancing into bedroom windows, while delivering books. b. Google looking into a great many other users’ personal data, so that it can organize your data in the usual way. c. The NSA eavesdropping on your phone conversations, while intending to gather only “metadata.” d. Traffic surveillance cameras identifying you by your Facebook photograph, so as to track your suspicious movements late at night. e. All of the above.

24. R U O K ? 21. Of what legal liability problems should an electronic healthcare system designer be wary? a. Accidental loss of a patient’s Holter heart monitor data that includes a life-threatening arrhythmia. b. Hackers turning off a controversial politician’s web-enabled cardiac pacemaker. c. Propagation of timely and accurate of alerts to health monitoring personnel. d. Doctors’ prescribing FDA-certified cell phone apps that help diabetics control their blood sugar. e. All of the above.

25. R U O K ? 22. Which of the following “experience enhancing” features have users come to expect in today’s wireless devices? a. Ability to communicate with all Bluetooth enabled devices in the local area. b. Embracing contextual changes, such as a distant cell tower handing off a mobile phone to a closer one. c. Cell phone automatically switching to your car’s speaker and microphone, when you step inside the vehicle. d. Automatically uploading photos to the cloud, when your cheap cell phone overflows. e. All of the above.

26. R U O K ? 23. Which of the following should be considered in the design of 10,000 networked bridge sensors? a. Any sensor should be able to spontaneously deliver data that suggests imminent structural failure. b. The sensors should be organized in a tree network, responding to queries like a tiny database. c. Temporally and geographically dispersed sensors may communicate via publish/subscribe middleware. d. All of the above. e. None of the above.

27. Summary • See pp.30, 31 in your textbook.

28. R U O K ? 24. Define “distributed system.” a. A collaborating network of autonomous computers. b. Autonomous computers working together to give the appearance of a single coherent system. c. Any processor seamlessly interfaced to a variety of peripheral devices. d. All of the above. e. None of the above.

29. R U O K ? 25. Which of the following is an advantage of distributed systems? a. They facilitate the integration of various computers’ apps into a single system. b. They scale to accommodate more users, widely separate resources and varying administrations. c. They completely hide intricacies related to the distribution of processes, data and control. d. They illuminate false assumptions about their underlying networks early in their development lifecycles. e. Both a and b above.

30. R U O K ? 26. Which of the following accurately describe distributed systems’ family tree? a. Computational, information processing and pervasive applications are the distributed system’s children . b. Clusters of similar resources and grids of dissimilar ones are the computational distributed system’s children. c. Transaction and office database processors are the distributed information system’s children. d. All of these may give birth to ubiquitous computing environments of small components that need no administration. e. All of the above.

31. R U O K ? 27. Which of the following accurately describe distributed systems’ family tree? a. Computational, information processing and pervasive applications are the distributed system’s children . b. Clusters of similar resources and grids of dissimilar ones are the computational distributed system’s children. c. Transaction and office database processors are the distributed information system’s children. d. All of these may give birth to ubiquitous computing environments of small components that need no administration. e. All of the above.

32. Venue Change • Let’s meet on Wednesday, August 27th, in ERB124, where many more MATLAB-equipped computers will be available than in the UC. • Everyone who has MATLAB on his/her laptop will want to bring it, because MATLAB runs very slowly on the heavily-loaded computers in ERB124. • After Wednesday, a great many probably will install MATLAB on their laptops, which will make the computers in ERB124 run faster. • Also please bring your completed Confidentiality Agreements, so that our grader can associate you with your teammates. Thanks!