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 Python 2.7Python 3.2Python 3.3
Windows (32-bit)
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Windows (64-bit)
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Mac OS X (10.5+)
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Linux (32-bit)
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Linux (64-bit)
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Lastest release
version 0.3.3 on Jan 5th, 2011

SLOW - The SLOSL Overlay Workbench

What is SLOW?

SLOW is a visual, integrated, rapid development environment for Internet overlay networks and Peer-to-Peer systems. It is strongly focused on the design of local topology decisions based on SLOSL and concepts from the database area. SLOW allows you to visually design and specify topologies and protocols in a platform and language neutral way. You can test them against different scenarios from within the workbench before you bet your money on their implementation. At any time, you can save the specification in OverML and generate a source code implementation from it.

What are SLOSL and OverML?

SLOW is based on the domain specific languages OverML and SLOSL. The Overlay Modelling Language OverML is an XML language for the specification of overlay protocols, topologies and node data. The SQL-Like Overlay Specification Language SLOSL is the topology specification language of OverML. It is based on SQL. There is also some additional information on the web.

Current status of SLOW:

The workbench is currently in alpha state. Some screenshots from the running system are on the Berlios developer site.

The complete workflow for design and testing is implemented, a number of overlay topologies were implemented (see the file example.xod in the source distribution). There is a preliminary Python execution environment for the specified overlays. Source code generation is unfinished. It obviously requires a generator for the target language. Current focus is on the languages Java and Python.


The workbench is written in Python 2.4. It requires PyQt3, lxml and MathDOM. Note that PyQt cannot be automatically installed by easy_install. If it is not yet available on your platform, you must install it manually before installing slow.

SLOW 0.3.2 and later require lxml 0.9 and MathDOM 0.7. Note that lxml requires libxml2 and libxslt to be installed.

Running Slow:

To run it, install the egg distribution with easy_install. This should generate a runnable script for your platform. On Linux, this is commonly /usr/bin/slow or ~/bin/slow or something similar.

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Last updated Jan 5th, 2011

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