[{Image src='boerger-egon-4.jpg' caption='' width='500' alt='Egon Börger' class='image_left'}]''__Ambient Abstract State Machines for modelling an architecture of current WEB applications systems__''\\ \\
[Egon Börger|User/Boerger_Egon], University of Pisa, Italy
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This is a report on the first steps of a recently started project with V. Gervasi, C. Dittamo, A. Cisternino, all U of
Pisa. We attempt there to discover the pattern underlying the large numer of different client-server architectures
for concurrent (distributed) WEB applications. The goal is to make such a structure explicit by defining precise
high-level models which can be refined to the major current implementations of WEB application architectures so
that as a result their differences can be precisely analyzed, i.e. stated and hopefully evaluated and classified.
To support the modelling of the various agents involved (for the components constituting the browser---like
launcher, netreader, parser, ECMAscript interpreter, renderer, etc.---and the server) we have defined a flexible
abstract ambient concept in terms of Abstract State Machines. It uniformly captures the common static and
dynamic disciplines for isolating states and concurrent behaviour as well as for sharing memory. We are
completing an ASM interpreter for ECAMScript programs, thus rigorously defining their dynamic semantics.
Currently we are modelling the various browser and server components.