A Network Monitoring System with a Peer-to-Peer Architecture (2009)
The ever growing complexity of modern data networks requires versatile and scalable network monitoring architectures. In this paper we propose a network monitoring system with a peer-to-peer (P2P)...
Hélder Veiga, Teresa Pinho, José Luis Oliveira, Rui Valadas, Paulo Salvador, António Nogueira
traffic monitoring for heterogeneous environments
Combining Node and Link Dimensioning for MPLS Networks Abstract (2008)
Luís Cardoso, Portugal Telecom Inovação, Jorge Patrão, Amaro De Sousa, Rui Valadas
This paper presents a procedure for Multi-Protocol Label Switching (MPLS) network dimensioning that deals with both the determination of the transmission facilities to be put in operation between...
Multi-time-scale traffic modeling using Markovian and L-Systems models (2008)
Paulo Salvador, António Nogueira, Rui Valadas, António Pacheco
Abstract. Traffic engineering of IP networks requires the characterization and modeling of network traffic on multiple time scales due to the existence of several statistical properties that are...
Framework based on stochastic L-Systems for modeling IP traffic with multifractal behavior (2008)
Paulo Salvador, António Nogueira, Rui Valadas
In a previous work we have introduced a multifractal traffic model based on so-called stochastic L-Systems, which were introduced by biologist A. Lindenmayer as a method to model plant growth....
Performance of Hierarchical Aggregation in Differentiated Services Networks (2008)
We address the use of hierarchical aggregation in DiffServ networks. We propose two analytical models to study the tradeoffs between signaling load and resource utilization. In the case of the...
Modeling Network Traffic with Multifractal Behavior (2008)
António Nogueira, Paulo Salvador, Rui Valadas, António Pacheco
Abstract. The traffic engineering of IP networks requires accurate characterization and modeling of network traffic, due to the growing diversity of multimedia applications and the need to...
Active traffic monitoring for heterogeneous (2008)
Hélder Veiga, Teresa Pinho, José Luis Oliveira, Rui Valadas, Paulo Salvador, António Nogueira
environments
Advanced Technologies for Infrared Wireless Indoor Local Area Networks 1 (2007)
António Tavares, Rui L. Aguiar, Rui Alves, Rui Valadas, Dinis M. Santos, A. Oliveira Duarte
The main degrading factor of infrared communication systems is the shot noise due to ambient light. Due to the directional nature of both signal and noise, the signal-to-noise ratio (SNR) at the...
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Luís Cardoso, Jorge Patrão, Carlos Lopes, Amaro De Sousa, Rui Valadas
This paper presents a tool for MPLS Traffic Engineering that allows for multi-hour dimensioning of networks supporting simultaneously peer-to-peer and client-server services. It is assumed that all...
Call Admission Control in IP networks with QoS support (2007)
Susana Sargento, Rui Valadas, Edward Knightly
Abstract 1 This paper addresses the problem of admission control for IP networks with QoS support. Several admission control architectures and algorithms are presented and compared. Special attention...
Cluster Analysis of Internet Users Based on Hourly Traffic Utilization (2007)
OLIVEIRA, Maria Rosário De, VALADAS, Rui, PACHECO, António, SALVADOR, Paulo
Internet access traffic follows hourly patterns that depend on various factors, such as the periods users stay on-line at the access point (e.g. at home or in the office) or their preferences for...
Performance of Hierarchical Aggregation in Differentiated Services Networks ° (2004)
Abstract- We address the use of hierarchical aggregation in DiffServ networks. We propose two analytical models to study the tradeoffs between signaling load and resource utilization. In the case of...
Multiscale fitting procedure using markov modulated poisson processes (2003)
Paulo Salvador, Rui Valadas, António Pacheco
This paper proposes a procedure for fitting Markov Modulated Poisson Processes (MMPPs) to traffic traces that matches both the autocovariance and marginal distribution of the counting process. A...
Multiscale fitting procedure using markov modulated poisson processes (2003)
Paulo Salvador, Rui Valadas, António Pacheco
Abstract. This paper proposes a parameter fitting procedure using Markov Modulated Poisson Processes (MMPPs) that leads to accurate estimates of queuing behavior for network traffic exhibiting LRD...
Resource stealing in endpoint controlled multi-class networks (2001)
Susana Sargento, Rui Valadas, Edward Knightly
Abstract. Endpoint admission control is a mechanism for achieving scalable services by pushing quality-of-service functionality to end hosts. In particular, hosts probe the network for available...
Resource stealing in endpoint controlled multi-class networks (2001)
Susana Sargento, Rui Valadas, Edward Knightly
Abstract. Endpoint admission control is a mechanism for achieving scalable services by pushing quality-of-service functionality to end hosts. In particular, hosts probe the network for available...