教案分布式計算chapter2slides

1、Slides for Chapter 2: Architectural ModelsFrom Coulouris, Dollimore and KindbergDistributed Systems: Concepts and DesignEdition 4, Pearson Education 2005Instructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.1Software a

2、nd hardware service layers in distributed systemsInstructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.2Clients invoke individual serversInstructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Conc

3、epts and Design Edn. 4 Pearson Education 2005 Figure 2.3A distributed application based on peer processesInstructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.4A service provided by multiple serversInstructors Guide fo

4、r Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.5Web proxy serverInstructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.6Web appletsInstructors Guide f

5、or Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.7Thin clients and compute serversThinClientApplicationProcessNetwork computer or PCCompute servernetworkInstructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Co

6、ncepts and Design Edn. 4 Pearson Education 2005 Figure 2.8Real-time ordering of eventsInstructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.9Processes and channelsInstructors Guide for Coulouris, Dollimore and Kindberg

7、 Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.10Omission and arbitrary failuresClass of failureAffectsDescriptionFail-stopProcessProcess halts and remains halted. Other processes maydetect this state.CrashProcessProcess halts and remains halted. Other processes may

8、not be able to detect this state.OmissionChannelA message inserted in an outgoing message buffer neverarrives at the other ends ing message buffer.Send-omissionProcessA process completes a send, but the message is not putin its outgoing message buffer.Receive-omissionProcessA message is put in a pro

9、cesss ing messagebuffer, but that process does not receive it.Arbitrary(Byzantine)Process orchannelProcess/channel exhibits arbitrary behaviour: it maysend/transmit arbitrary messages at arbitrary times,commit omissions; a process may stop or take anincorrect step.Instructors Guide for Coulouris, Do

10、llimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.11Timing failuresClass of FailureAffectsDescriptionClockProcessProcesss local clock exceeds the bounds on itsrate of drift from real time.PerformanceProcessProcess exceeds the bounds on the intervalb

11、etween two steps.PerformanceChannelA messages transmission takes longer than thestated bound.Instructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.12Objects and principalsInstructors Guide for Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edn. 4 Pearson Education 2005 Figure 2.13The enemyCommunication channelCopy of mProcess pProcess qmThe enemymInstructors Guide for Co