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With the development and deployment of new applications and services over the Internet, it is necessary to determine the impact that they have on availability, losses and errors, delay, and bandwidth. The quality of service and the traffic engineering applied in the design of the networks require performance to be guaranteed, and the most important parameter is the one-way delay (OWD). Properly estimating the OWD and its components is not an easy task, because there are critical factors such as synchronization, operating systems, network topology, among others. In this work we analyze the OWD components in a point-to-point scenario, with emphasis on queuing delay, by implementing QoS policies that allow obtaining delay data using real traffic patterns. Finally, we model the predictive behavior of OWD; the results show that it adjusts to a Polynomial Regression. [ABSTRACT FROM AUTHOR]

With the deployment of new devices, protocols and applications, network traffic is changing to adapt to these trends. Therefore, it is necessary to analyze the impact over services and resources in data networks. Traffic classification of network is an important requirement to optimize traffic engineering and adequately provision quality of service. In this paper, we analize the variable packet size of the traffic in an university campus heterogenuos network (wired and wireless) throught the collected data using a novel sniffer that ensures the user data privacy. We separate the collected data in each scenario, by type of traffic, protocols and applications in order to compare the behavior of packet length. Finally, we estimate the traffic model that represents this traffic by means of probability distribution and compute its associated numerical parameters. [ABSTRACT FROM AUTHOR]

In this paper, we address the problem of optimizing resources for downlink transmission in a macro-femtocell network under non-dense femtocell deployment. In the literature, some approaches perform bandwidth or power optimization depending on the air interface technology and others optimize both types of resources, but only in femtocell network. However, the following limitations can be noticed: (1) Equal distribution of transmitted power among all subcarriers, even if they are not used, leads to resource underutilization, (2) femtocell data rates are reduced in order to minimize the interference from femto base stations to macro users, and (3) the impact of noise has not been evaluated. Moreover, there is lack of optimal selection of users that can be served by femtocells. To overcome these limitations, we propose a model that finds a tradeoff between bandwidth and power to reduce the bandwidth usage per user and to minimize the impact of noise. By means of Linear Programming, our solution maximizes user satisfaction and provides optimal: serving base station, power and bandwidth for each mobile user taking into account its location and demand. Furthermore, we present a performance analysis under changes of signal to noise ratio. Simulations were conducted and a comparison with a modified version of Weighted Water Filling algorithm is presented. [ABSTRACT FROM AUTHOR]

Femtocells (FCs) are introduced to enhance the indoor coverage and system capacity of traditional cellular networks. However, the network performance could be significantly deteriorated due to the increase in cochannel interference in dense deployment. In the literature, three spectrum usage schemes that deal with the cross-tier interference have been proposed, i.e., orthogonal assignment, underlay, and controlled underlay using mainly closed-access FCs. This paper targets the optimization of resource allocation, together with the selection of base stations (BSs) in two-tier networks assuming hybrid access FCs, to reduce the cross-tier interference. Moreover, this model aims to achieve effective spatial reuse between the macrocell (MC) and FCs while guaranteeing quality-of-service (QoS) transmissions by means of joint power control in both tiers. Simulations are conducted to show a comparison with the other three approaches. [ABSTRACT FROM AUTHOR]

Our built world is one of the most important factors for a livable future, accounting for massive impact on resource and energy use, as well as climate change, but also the social and economic aspects that come with population growth. The architecture, engineering, and construction industry is facing the challenge that it needs to substantially increase its productivity, let alone the quality of buildings of the future. In this article, we discuss these challenges in more detail, focusing on how digitization can facilitate this transformation of the industry, and link them to opportunities for visualization and augmented reality research. We illustrate solution strategies for advanced building systems based on wood and fiber. [ABSTRACT FROM AUTHOR]