... many distributed systems,
and are discussed extensively in this chapter. The main difficulty in designing
secure distributed systems is not so much caused by security mechanisms, but by
SEC. 8 .6
RECOVERY
369
Coordinated ... checkpoints and
message logging. Elnozahy et al. (2002) provide a survey of checkpointing and
logging in distributed systems. Various algorithmic detai...
... 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 message-oriented systems ... message-
oriented communication in distributed systems by first taking a closer look at
what exactly synchronous behavior is and what its implications are. Then, we dis-
cuss m...
... 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 systems.
The ... architectures and software architectures. On the one hand, we
need to organize the components of a distributed system such that monitoring and
adjustments can be done, while on the...
... defined the second to be the time it
takes the cesium 133 atom to make exactly 9,192 ,63 1,770 transitions. The choice
of 9,192 ,63 1,770 was made to make the atomic second equal to the mean solar
second ... anything to do with papal decrees and did not
accept the Gregorian calendar for 170 years.
Figure 6- 3. TAl seconds are of constant length, unlike solar seconds. Leap
seconds are...
... is known as a write-back
cache, which is, again, mainly applied in distributed file systems.
268
SYNCHRONIZATION
CHAP. 6
Figure 6- 22. Election algorithm in a wireless network, with node a as the ... 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-under-...
... the 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
1980s. ... generation of distributed systems. In this section, we will first take
a deeper look into the general architecture of object-based distributed systems,
after which we can se...
... 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...
... 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 ... can be enforced. Clearly, whenever a main document is changed. a
DISTRIBUTED WEB-BASED SYSTEMS
CHAP. 12
564
DISTRIBUTED WEB-BASED SYSTEMS
CHAP. 12
Figure 12-12. (a) HTTP request message. (b) H...