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Connectivity Models


The testing of the performance of delay tolerant communication protocols and systems is usually done through simulation as i) deployments are expensive and should be left to the final stage of the development process, and ii) the number of varying parameters in these systems is so high that it would be very hard to conduct thorough testing of all the functionality within a single deployment. Therefore, protocols are often plugged into mobility simulators to test their performance; however, until recently, most of the testing has been conducted with random mobility models which do not mirror reality. Furthermore, despite disconnections playing a very prominent role in the performance of any delay tolerant mobile system, most models do not really account for it. A different approach to the performance evaluation of this class of systems is the use of real traces of movement collected in specific domains. However, these traces do not allow for flexible performance testing, as they are specific for a given scenario with fixed connectivity properties.

For these reasons, we designed the Connectivity Trace Generator (CTG), a tool for the automatic generation of connectivity traces, which takes as input real mobility traces and is able to output a set of traces with similar connectivity properties. This allows system designers to investigate the impact of the variation of connectivity patterns, number of hosts, and other parameters on the protocol or system under investigation. 

People Involved

Software Download

We are happy to share the code of the Connectivity Trace Generator with you. The code can be obtained by filling a request form that can be found here.


Mobility Models for Systems Evaluation. A Survey
Mirco Musolesi and Cecilia Mascolo
Book Chapter in Middleware for Network Eccentric and Mobile Applications. Benoît Garbinato, Hugo Miranda andd Luís Rodrigues Editors. Springer. 2009.

CTG: A Connectivity Trace Generator for Testing the Performance of Opportunistic Mobile Systems
Roberta Calegari, Mirco Musolesi, Franco Raimondi and Cecilia Mascolo.
In Proceedings of the European Software Engineering Conference and the International ACM SIGSOFT Symposium on the Foundations of Software Engineering (ESEC/FSE07). Dubrovnik, Croatia. September 2007. ACM Press.


This library is free software; you can redistribute it and/or modify under the terms of the GNU Lesser General Public License as published by Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope it will be useful but without any warranty, without even the implied warranty of merchantability or fitness for a particular purpose. See the GNU Lesser General Public License for more details.


Please contact Mirco Musolesi sending an email to mirco.musolesi [AT]