DISTRIBUTED SYSTEMS principles and paradigms Second Edition phần 4 ppt

... shown in Fig. 5- 14. In distributed systems, name servers in the global and administrational layer are the most difficult to implement. Difficulties are caused by replication and cach- ing, which ... large number of days and taking the average before divid- ing by 86 ,40 0. The resulting quantity was called the mean solar second. With the invention of the atomic clock in 1 948 , i...

Ngày tải lên: 08/08/2014, 21:22

... receiver. The sender and receiver can execute completely 160 COMMUNICA nON CHAP. 4 Figure 4- 26. A general architecture for streaming stored multimedia data over a network. 4. 4.2 Streams and Quality of ... procedures are the ones responsible for collecting and SEC. 4. 4 STREAM-ORIENTED COMMUNICATION 163 4. 4.3 Stream Synchronization An important issue in multimedia systems is t...

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... checkpointing, is often more popular, and will presumably stay so even when systems grow to much larger sizes (Elnozahy and Planck, 20 04) . 3 74 FAULT TOLERANCE CHAP. 8 not change and which messages are reliably ... concerning checkpoints and message logging. Elnozahy et al. (2002) provide a survey of checkpointing and logging in distributed systems. Various algorithmic detai...

Ngày tải lên: 08/08/2014, 21:22

... 145 4. 3.3 Example: ffiM's WebSphere Message-Queuing System 152 4. 4 STREAM-ORIENTED COMMUNICATION 157 ,4. 4.1 Support for Continuous Media 158 4. 4.2 Streams and Quality of Service 160 4. 4.3 ... components across a CONTENTS ix 4. 2.3 Asynchronous RPC 1 34 4.2 .4 Example: DCE RPC 135 4. 3 MESSAGE-ORIENTED COMMUNICATION 140 4. 3.1 Message-Oriented Transient Communication 141...

Ngày tải lên: 08/08/2014, 21:22

... of distributed systems when decisions are taken about where components are placed, for example. We discuss such system architectural issues next. 2 .4 SELF -MANAGEMENT IN DISTRIBUTED SYSTEMS Distributed ... one for handling interaction with the user and SEC. 2.2 SYSTEM ARCHITECTURES 53 Collaborative Distributed Systems Hybrid structures are notably deployed in collaborative...

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... the issue of how processes in distributed systems synchronize. Synchronization is all about doing the right thing at the right time. A problem in distributed systems, and computer networks in general, ... used to handling replication, let alone understanding what it means to provide detailed information on consistency. Therefore, it is mandatory that there are simple and easy-to-un...

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... the capability), and then runs the result through a one-way function. 44 4 DISTRIBUTED OBJECT-BASED SYSTEMS CHAP. 10 Object orientation began to be used for developing distributed systems in the 1980s. ... participate in the attack. Specht and Lee (20 04) distinguish two types of attacks: those aimed at bandwidth depletion and those aimed at resource depletion. Bandwidth deplet...

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... If this 11 DISTRIBUTED FILE SYSTEMS Considering that sharing data is fundamental to distributed systems, it is not surprising that distributed file systems form the basis for many distributed ... systems and applications. In this chapter, we consider distributed file systems as a paradigm for general-purpose distributed systems. 11.1 ARCHITECTURE We start our discussi...

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... 566 DISTRIBUTED WEB;.BASED SYSTEMS CHAP. 12 12.3.2 Simple Object Access Protocol Where HTTP is the standard communication protocol for traditional Web- based distributed systems, the ... indicates that a request could be honored, and has the asso- ciated phrase "OK." Other frequently used codes are: 40 0 (Bad Request) 40 3 (Forbidden) 40 4 (Not Found). A request or respo...

Ngày tải lên: 08/08/2014, 21:22