DISTRIBUTED SYSTEMS principles and paradigms Second Edition phần 9 docx

... (Sun Microsystems, 2005b) and JavaSpaces (Freeman et al., 199 9) are mostly based on central servers. Let us take a look at two typical examples. Example: Jini and JavaSpaces Jini is a distributed ... application server, and a database. The Web server is the traditional Web server that we had before; the DISTRIBUTED WEB-BASED SYSTEMS CHAP. 12 SEC. 13.2 ARCHITECTURES 599 identifi...

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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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... 288 7.3.1 Eventual Consistency 2 89 7.3.2 Monotonic Reads 291 7.3.3 Monotonic Writes 292 7.3.4 Read Your Writes 294 7.3.5 Writes Follow Reads 295 DISTRIBUTED SYSTEMS Second Edition 14 INTRODUCTION CHAP. ... publish/subscribe systems form an important and expanding class of distributed systems. We will discuss them at length in Chap. 13. 1.3.3 Distributed Pervasive System...

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... connection requests, and hands off such connec- tions to one of the servers (Hunt et al, 199 7; and Pai et al., 199 8). The principle working of what is commonly known as TCP handoff is shown in ... one for handling interaction with the user and SEC. 2.2 SYSTEM ARCHITECTURES 53 Collaborative Distributed Systems Hybrid structures are notably deployed in collaborative distributed s...

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... ( 199 8) and Gropp et al. (l 998 a) 4.3.2 Message-Oriented Persistent Communication We now come to an important class of message-oriented middle ware services, generally known as message-queuing systems, ... distributed systems and applications are built directly on top of the sim- ple message-oriented model offered by the transport layer. To better understand and appreciate the me...

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... defined the second to be the time it takes the cesium 133 atom to make exactly 9, 192 ,631,770 transitions. The choice of 9, 192 ,631,770 was made to make the atomic second equal to the mean solar second ... ticks of the cesium 133 clocks since midnight on Jan. 1, 195 8 (the beginning of time) divided by 9, 192 ,631,770. Although TAl is highly stable and available to anyone who wan...

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... criteria are often maintained to classify caching protocols (Min and Baer, 199 2; Lilja, 199 3; and Tartalja and Milutinovic, 199 7). First, caching solutions may differ in their coherence detection ... to use voting as origi- nally proposed by Thomas ( 197 9) and generalized by Gifford ( 197 9). The basic idea is to require clients to request and acquire the permission of multiple...

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... checkpoints and message logging. Elnozahy et al. (2002) provide a survey of checkpointing and logging in distributed systems. Various algorithmic details can be found in Chow and Johnson ( 199 7). 8.6.2 ... mentioned protocols, are common to many distributed systems, and are discussed extensively in this chapter. The main difficulty in designing secure distributed systems is...

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... capability), and then runs the result through a one-way function. 444 DISTRIBUTED OBJECT-BASED SYSTEMS CHAP. 10 Object orientation began to be used for developing distributed systems in the 198 0s. Again, ... resolution is handled by class loaders, which need to be adapted to implement this approach. Details of how this can be done can be found in Wallach et al. ( 199 7). 434 SECUR...

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