University of Southern California/Information Sciences Institute
4676 Admiralty Way #1001
Marina Del Rey, CA 90292

Research Project:
Virtual InterNetwork Testbed (VINT):


The VINT project is currently:

Ultimately, VINT will enable more rapid design and evaluation of protocols and thereby directly contribute to the evolvability of the global information infrastructure.

This work is being performed in collaboration with LBNL, UC Berkeley, and Xerox PARC.



Development and release of phase 1 VINT/ns detailed simulator, including basic network protocol modules, traffic, and topology libraries:

Initial results of protocol stress testing method by subjecting localized protocol mechanisms to complete error-scenario generation. Applied to multicast routing protocol.

Initial enhancement of network animation techniques (nam2) to capture link, node, and protocol state dynamics.

Evaluations of performance bottlenecks in simulation environment--memory and runtime.


Continued development and release of improvements to phase 1 VINT detailed simulator including new and enhanced network protocol modules, traffic and topology libraries.

Development of a prototype session level simulator with common interfaces, protocol modules, and a network protocol description interface. Initial target application is reliable multicast protocol design.

Phase 1 Visualization tools for both detailed and session level simulators.

Results of protocol studies completed using VINT/ns, including the behavior of reliable multicast protocols in the presence of dynamic topologies, robustness testing methods for soft-state protocols, web caching mechanisms and underlying multicast delivery, as examples.


In September of this year the first VINT/ns workshop will be held in conjunction with ACM as an opportunity to introduce the larger community to our tools.

Significant effort is being focussed on tool support for reliable multicast protocol design with the hope of engaging the IRTF reliable multicast group to use VINT/ns as their evaluation platform. This will allow the evaluation of one of the ultimate goals of the project, namely promoting VINT simulations as a community standard for comparisons in published work. Similar efforts will be made in the context of multicast routing and queue management and scheduling mechanisms.

VINT/ns is already a common evaluation platform for TCP research, and we are continuing additions to VINT/ns to support that community.

The software availabe from the project are:

Tcl-v7.6, Tk-v4.2, OTcl-v0.96 and the latest version of libTcl available from the ns home page need to be installed to run the software.

To view the quad chart for VINT click here