Dissertaç ˜ao de Mestrado Mestrado em Engenharia Informática Jo ...
Dissertaç ˜ao de Mestrado Mestrado em Engenharia Informática Jo ...
Dissertaç ˜ao de Mestrado Mestrado em Engenharia Informática Jo ...
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2<br />
State of the Art and Related Work<br />
This section aims at presenting the state of the art in automatic application configuration, as<br />
well as studying the tools which may be used to tackle the probl<strong>em</strong> i<strong>de</strong>ntified in Chapter 1.<br />
To better un<strong>de</strong>rstand the outlines of the probl<strong>em</strong>, this section starts by explaining the con-<br />
text of this dissertation. Namely, the virtual appliances th<strong>em</strong>e is explored with the purpose of<br />
making it more natural.<br />
Afterwards, the existing techniques to <strong>de</strong>al with the probl<strong>em</strong> are analysed. There is, never-<br />
theless, a particularity regarding this part. As previsouly mentioned in Chapter 1, the configu-<br />
ration of applications is still mostly a manual task. As such, the existing references consi<strong>de</strong>rably<br />
relevant to this th<strong>em</strong>e are very few. Therefore, this dissertation consists on one of the first con-<br />
tributions for the probl<strong>em</strong> of automatic configuration of applications.<br />
Finally, the adopted concepts and tools to mitigate the probl<strong>em</strong> are analysed. The automatic<br />
file recognition th<strong>em</strong>e is studied by i<strong>de</strong>ntifying two parser generators and <strong>de</strong>scribing th<strong>em</strong>.<br />
Finally, it is seen how the file can be represented in an abstract, in<strong>de</strong>pen<strong>de</strong>nt from its original<br />
language, way.<br />
2.1 Virtual Appliances<br />
A Virtual Appliance (VA) is a minimal virtual machine (VM, Section 2.1.1) composed of pre-<br />
configured and pre-installed applications plus an optimized operating syst<strong>em</strong> called Just<br />
Enough Operating Syst<strong>em</strong> (JeOS) (Figure 2.1). VAs are normally created to perform a specific<br />
task in the most effective way, therefore they only contain the essential and necessary resources<br />
for the execution of that task, contrary to the regular VM where all of the kernel OS features are<br />
present, even those whose use is seldom.<br />
11