Search results for "Quality of service"

Comparing changes in productivity among private water companies integrating quality of service: A metafrontier approach

2019

Abstract Most previous studies evaluating the effect of ownership on the performance of water companies have ignored the fact that there are several types of private water companies. In this study, we instead recognize that private water companies can differ considerably in how they are managed, based on whether their infrastructure is privately or publicly owned. We estimated change in productivity of fully-privatized companies and concessionary companies by employing the metafrontier Malmquist Luenberger productivity (MMLP) index, which allowed us to integrate quality-of-service variables as undesirable outputs. We segregated the MMLP index to assess changes over time in relative efficien…

2020

The growth of cloud-based services is mainly supported by the core networking infrastructures of large-scale data centers, while the scalability of these services is influenced by the performance and dependability characteristics of data centers. Hence, the data center network must be agile and reconfigurable in order to respond quickly to the ever-changing application demands and service requirements. The network must also be able to interconnect the big number of nodes, and provide an efficient and fault-tolerant routing service to upper-layer applications. In response to these challenges, the research community began exploring novel interconnect topologies, namely: Flecube, DCell, Ficonn…

Efficient Switches with QoS Support for Clusters

2007

Current interconnect standards providing hardware support for quality of service (QoS) consider up to 16 virtual channels (VCs) for this purpose. However, most implementations do not offer so many VCs because they increase the complexity of the switch and the scheduling delays. We have shown that this number of VCs can be significantly reduced, because it is enough to use two VCs for QoS purposes at each switch port. In this paper, we cover the weaknesses of that proposal and, not only we reduce VCs, but we also improve performance due to the flexibility assigning buffer memory.

Autonomous management of Quality of Service and security in an Internet of Things environment

2019

Nowadays, the Internet of Things (IoT) is becoming important in our daily lives thanks to technological advances. This paradigm aims to improve the quality of human life through automating several tasks. In this context, service level guarantee within IoT environments is a major challenge while considering a massive deployment of IoT applications and services as well as extending their usage to different domains. The IoT service level can be characterized in two parts: Quality of Service (QoS) and security. Moreover, this service level must be managed in an autonomic manner within the IoT environment given the heterogeneity and the size of its infrastructure making it difficult, even imposs…

Energy Harvesting Enabled Energy Efficient Cognitive Machine-to-Machine Communications

2020

Energy harvesting based cognitive machine-to-machine (EH-CM2M) communication has been introduced to overcome the problem of spectrum scarcity and limited battery capacity by enabling M2M transmitters (M2M-TXs) to harvest energy from ambient radio frequency signals, as well as to reuse the resource blocks (RBs) allocated to CUs in an opportunistic manner. However, the complex interference scenarios and the stringent QoS requirements pose new challenges on resource allocation optimization. In this chapter, we consider how to maximize the energy efficiency of M2M-TXs via the joint optimization of channel selection, peer discovery, power control, and time allocation.

Analysis of the impact of length of stay on the quality of service experience, satisfaction and loyalty

2017

Although length of stay is a relevant variable in destination management, little research has been produced connecting it with tourists' post-consumption behaviour. This research compares the post-consumption behaviour of same-day visitors with overnight tourists in a sample of 398 domestic vacationers at two Mediterranean heritage-and-beach destinations. Although economic research on length of stay posits that there are destination benefits in longer stays, same-day visitors score higher in most of the post-consumption variables under study. Significant differences arise in hedonic aspects of the tourist experience and destination loyalty. Thus, we propose that length of stay can be used a…

Social Network-Based Content Delivery in Device-to-Device Underlay Cellular Networks Using Matching Theory

2017

With the popularity of social network-based services, the unprecedented growth of mobile date traffic has brought a heavy burden on the traditional cellular networks. Device-to-device (D2D) communication, as a promising solution to overcome wireless spectrum crisis, can enable fast content delivery based on user activities in social networks. In this paper, we address the content delivery problem related to optimization of peer discovery and resource allocation by combining both the social and physical layer information in D2D underlay networks. The social relationship, which is modeled as the probability of selecting similar contents and estimated by using the Bayesian nonparametric models…

Achieving Fair Load Balancing by Invoking a Learning Automata-Based Two-Time-Scale Separation Paradigm.

2020

Author's accepted manuscript. © 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. In this article, we consider the problem of load balancing (LB), but, unlike the approaches that have been proposed earlier, we attempt to resolve the problem in a fair manner (or rather, it would probably be more appropriate to describe it as an ε-fair manner because, although the LB…

Revenue-based adaptive deficit round robin

2005

This paper presents an adaptive resource allocation model that is based on the DRR queuing policy. The model ensures QoS requirements and tries to maximize a service provider's revenue by manipulating quantum values of the DRR scheduler. To calculate quantum values, it is proposed to use the revenue criterion that controls the allocation of free resources. The simulation considers a single node with the implemented model that serves several service classes with different QoS requirements and traffic characteristics. It is shown that the total revenue can be increased due to the allocation of unused resources to more expensive service classes. At the same time, bandwidth and delay guarantees…

Energy-efficient resource allocation for OFDMA two-way relay networks with imperfect CSI

2015

Most of the existed works on the radio resource allocation (RRA) problem commonly assume the channel-state information (CSI) can be perfectly obtained by the transmission source. However, such assumption is not practical in the realistic wireless systems. In this work, we consider the practical implementation issues of resource allocation in orthogonal frequency division multiple access (OFDMA) two-way relay networks: the inaccuracy of channel-state information (CSI) available to the source. Instead, only the estimated channel status is known by the source. In this context, a joint optimization of subcarrier pairing and allocation, relay selection, and transmit power allocation is formulate…