Phd Dissertation

Título:"Reserva eficiente de Recursos en Redes para Transmision en Tiempo Real".

Director: Joan Vila i Carbó.
Departamento: Informática de Sistemas y Computadores.
Universidad Politécnica de Valencia. Spain.

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Brief description of my Phd. in english.

Abstract

  The demand of Quality of Service (QoS) and real-time channels on computer networks has recently increased due to the development of new multimedia applications.
    This multimedia transmission requires a very demanding reservation of network resources. This is due mainly to the traffic characteristics and the quality of service the applications require.
    This transmission is usually done using a channel. Channel establishment requires reserving some network resources (bandwidth and buffers) in order to implement the real-time channel. This reservation mainly depends on traffic characteristics, but also on network parameters.
    Multimedia traffic usually has a very variable transmission rate (VBR). That implies that in order to guarantee the quality of service, the reservation of network resources is very high. However, these resources are usually misused when transmission rate is low.
    Therefore, the optimisation of network resources is a key issue. There is a need for methods that obtain the optimal reservation of network resources which guarantee quality of service. These methods must be efficient enough in order to be used on-line.
    In this dissertation, some new schemes to save network resources are introduced. The first method is based on generating a set of points from the stored video with an off-line analysis of its empirical envelope, and then using these points to efficiently calculate the optimal bandwidth reservation for a given channel, at channel establishment time. These points are used to optimise the buffer node. In both cases, a leaky or token bucket flow specification is used. Finally, a new scheme for fault detection for highly available real-time channels is developed. This new scheme provides an efficient resource reservation and it is based on "suspecting" a failure when the packet delay through the primary channel is close to the maximum guaranteed delay. Theses schemes have been proved using MPEG traffic traces.

Index

  1. 1.- Introduction
  2. 2.- Real-time transmission
  3. 3.- Traffic characterization
  4. 4.- Optimal bandwidth reservation
  5. 5.- Optimization of buffer in a network node
  6. 6.- Efficient resource reservation for backup channel
  7. 7.- Conclussions
  8. A1.- MPEG traces
  9. A2.- Introduction to RTNetSim
  10. A3.- ORNET: A network model
  11. A4.- Acronyms

References

Most of the chapter 4 can be found in:
  1. Enrique Hernández Orallo and Joan Vila i Carbó;. "A fast method to optimise network resources for Video-on-Demand Transmission". Euromicro’2000 
  2. Enrique Hernández Orallo and Joan Vila i Carbó.A New Approach to Optimise Bandwidth Reservation for Real-Time Video Transmission with Deterministic Guarantees" In Real-Time Imaging, vol 9, Issue 1, Feb. 2003, pp. 11-26, ISSN 1077-2014, Academic Press.
 The first part of the chapter 5 can be found in:
  1. Enrique Hernández Orallo and Joan Vila i Carbó. "An optimal method for Allocating Buffer for Bandwidth for MPEG Traffic in a Network Node". Euromicro’2001 
The chapter 6 can be found in:
  1. Enrique Hernández Orallo and Joan Vila i Carbó. "Evaluation of a new resource reservation scheme for MPEG transmission in highly available real-time channels". 5th IFIP TC6 International Simposium.
  2. Enrique Hernández Orallo and Joan Vila i Carbó. "An efficient resource reservation scheme for highly available real-time channels." PDCS’99.

You can download the papers here: papers