Former projects developed at LAND:


COMIT Project

ALMADEM Project (Concluded)

PRONEX Project

Modeling and Analysis of Wireless Access Systems to the Internet

Modeling and Analysis of Multimidia Aplications/CNPq

Project Summary



Anna Dolejsi Santos (UFF)

Berthier A. Ribeiro Neto (UFMG)

Edmundo de Souza e Silva (coordinator) (UFRJ)

Rosa Maria M. Leão (UFRJ)

Valmir Carneiro Barbosa (UFRJ)



COMIT Project (September, 2000 - September, 2003)
COntinuos Media over InTernet

Project Summary

Future networked multimedia information systems will carry a wide variety of applications including digital libraries, video, audio and image services, distance learning and collaboration, networked virtual environments, and entertainment. The main characteristics of multimedia applications that lead to difficulties in end-to-end systems design are that they have very large bandwidth and storage requirements, with vastly different performance and reliability requirements, often coupled with real-time constraints. Along with these characteristics, the highly interactive nature of a variety of multimedia applications, resulting in fairly unpredictable workloads, makes the design and evaluation of networked multimedia information systems an exceptionally challenging problem.

This project will outline research on three aspects of this problem:

  • the design and evaluation of server resource allocation algorithms for CM servers in order to retrieve information efficiently and according to the QoS demanded by the application;

  • the development and evaluation of application-level mechanisms for enhancing quality of service delivered by the network to networked multimedia applications;

  • the development of performance evaluation techniques for evaluating new server designs.

The participants have available four prototypes of state of the art multimedia systems: the Virtual World Data Server (VWDS) developed at UCLA; the prototype of a Video-on-Demand server developed in Brazil as part of the cooperative research project among Brazilian institutions; and the Multimedia Asynchronous Networked Individualized Courseware (MANIC) and the Internet Multimedia Proxy (IMP) both developed at UMass.

These applications will be used to motivate the development of new algorithms for retrieving information and for maintaining the desired quality of service after sending the data over a wide area network. They will also form the basis of the many experimental and analytical studies that will be performed to evaluate these new algorithms. To aid in this evaluation, our group also developed three performance evaluation and modeling tools: a state-of-the-art tool for constructing performance and reliability models (Tangram-II) developed in Brazil jointly with UCLA; a symbolic model checking tool (VERUS); and a tool which facilitates design, development, and subsequent performance evaluation of designs of multimedia storage hierarchies (ViPEr-HiSS) under development at UMD.



Berthier Ribeiro de Araujo Neto (UFMG)

Edmundo de Souza e Silva (coordinator) (UFRJ)

Paulo Henrique Aguiar Rodrigues (UFRJ)

Rosa Maria M. Leão (UFRJ)

Sergio Vale Aguiar Campos (UFMG)


Donald Towsley (University of Massachusetts, Amherst)

Jim Kurose (University of Massachusetts, Amherst)

Leana Golubchik (University of Maryland)

Richard Muntz (University of California, Los Angeles) - Coordinator



Almadem Project (January, 1997 - April, 2000)
Applications and Analysis of Multimedia High Performance Networks

Project Summary

The main goal of the ALMADEM research proposal was to combine basic research in computer networks with the development of designing tools and laboratory tests to understand many networking design issues and propose new solutions. Yet we propose to build multimedia applications to test several of our ideas. In summary, the research proposal focused on a whole cycle of technology development, from theory to prototyping. The proposal can be divided into three major sets of activities:

  • Fundamental Research in Computer Networks, including:

    1. development of new modeling and analysis techniques aiming at the evaluation of computer networks;

    2. evaluation and development of basic control algorithms for multimedia networks;

    3. traffic modeling.

  • Modeling and analysis tools that incorporate the state of the art in analysis techniques as well as new ones developed during the project. The tools would include analytical and simulation methods to be used in the analysis of high performance networks. Libraries of models and traffic simulators would be included. Testbeds would be designed to study the behavior of control policies used in high performance networks.

  • Development of applications including:

    1. multimedia applications tools and network design tools;

    2. a low cost Video on Demand (VoD) prototype.

Main Results

  • Modeling and Analysis: Development of network models, development of new solution techniques to solve complex models of multimedia networks and traffic modeling.

  • Modeling Tools: TANGRAM-II, VERUS

  • Multimedia Tools : Whiteboard, Voice Transmission Tool, VoD server

  • Developing Laboratories : Three laboratories at UFRJ, UFMG and UFPE were established. In these laboratories we developed testbeds and a number of experiments to studies issues related to high-speed multimedia networks.


Edmundo de Souza e Silva (coordinator) (UFRJ)

Sergio V.A. Campos (UFMG)

Rosangela Coelho (PUC-RIO)

Nelson Fonseca (Unicamp)

Rosa M. M. Leão (UFRJ)

Berthier Ribeiro Neto (UFMG)

Paulo Henrique A. Rodrigues (UFRJ)

José Augusto Suruagy Monteiro (UFPe)

Jorge Moreira de Souza (CPqD-TELEBRAS)

Sibelius Lellis Vieira (UFG)

Wellington Santos Martins (UFG)

Final Report ( - download



PRONEX Project (1996 - 2002)
Modelagem Computacional e Computação de Alto Desempenho

Main Goals

  • Development of new techniques to solve complex models of computer and communication systems.

  • Integrate the new methods in the TANGRAM-II tool.

  • Develop experiments to study issues related to multimedia networks.



Modeling and Analysis of Wireless Access Systems to the Internet (2000 - 2002)

Main Goals

  • Internet traffic characterization.

  • Internet traffic modeling.

  • Modeling,Analysis and Dimensioning of a wireless access system.


Edmundo de Souza e Silva (UFRJ)

Rosa Maria M. Leão (UFRJ)

Tânia Regina Tronco Fudoli (CPqD)


CPqD - Lucent