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The Credo Methodology
(Extended Version)
Immo Grabe
1
, Mohammad Mahdi Jaghoori
1
, Joachim Klein
3
,
Sascha Kluppelholz
3
, Andries Stam
6
,ChristelBaier
3
, Tobias Blechmann
3
,
Bernhard K. Aichernig
5
, Frank de Boer
1
, Andreas Griesmayer
5
,
Einar Broch Johnsen
2
, Marcel Kyas
9
, Wolfgang Leister
8
, Rudolf Schlatte
2
,
Martin Steffen
2
, Simon Tschirner
4
,LiangXuedong
7
, and Wang Yi
4
1
CWI, Amsterdam, The Netherlands
2
University of Oslo, Norway
3
Technische Universitat Dresden, Germany
4
University of Uppsala, Sweden
5
UNU - IIST, Macau, China
6
Almende, The Netherlands
7
RRHF, Oslo, Norway
8
NR, Oslo, Norway
9
Freie Universitat Berlin, Germany
Abstract.
This paper is an extended version of the
Credo
Methodol-
ogy [16].
Credo
offers tools and techniques to model and analyze highly
reconfigurable distributed systems. In a previous version we presented
an integrated methodology to use the
Credo
tool suite. Following a com-
positional, component-based approach to model and analyze distributed
systems, we presented a separation of the system into components and
the network. A high-level, abstract representation of the dataflow level
on the network was given in terms of behavioral interface automata and
a detailed model of the components in terms of Creol models. Here we
extend the methodology with a detailed model of the network connect-
ing these components. The
Vereofy
tool set is used to model and analyze
the dataflow of the network in detail. The behavioral automata connect
the detailed model of the network and the detailed model of the compo-
nents. We apply the extended methodology to our running example, a
peer-to-peer file-sharing system.
1
Introduction
Current software development methodologies follow a component-based approach
in modeling distributed systems. A major shortcoming of the existing methods
is the lack of an integrated formalism to model highly reconfigurable distributed
systems at different phases of design, i.e., systems that can be reconfigured in
This work has been funded by the European IST-33826 STREP project CREDO
on Modeling and Analysis of Evolutionary Structures for Distributed Services.
(
http://credo.cwi.nl
)
