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In a multiuser scenario, the bit-loading, which has proven decisive in resource optimization for Power Line Communications (PLCs), has to be coupled with channel assignment to fully exploit its potential. Unfortunately, finding the most performing combination of channel and power allocation leads to integer (or mixed) programming problems, which are known to be NP-hard. To overcome the complexity...
In this paper we present a new admission control (AC) for IEEE 802.16. The AC aims to accept new connections according to the negotiated service class (UGS, rtPS, nrTPS, and BE). To achieve this goal we propose to use the token bucket concept that provide QoS for real time traffics without degrading the QoS of non real time traffic. To show the benefit of the proposed AC, an analytical model based...
An accurate estimation of the available bandwidth of mesh nodes is the essential prerequisite of admission control mechanism, which provides QoS assurance in wireless mesh networks. Existing bandwidth estimation schemes do not accurately consider the influence of parallel transmission due to spatial reuse and act overly conservative. In this study, we proposed an accurate bandwidth estimation scheme,...
Admission control plays an important role in providing Quality of Service (QoS) guarantees for wireless mesh networks (WMNs). Multipath routing can improve network performance in reliability and load balancing. However, when the multipath routing are adopted in 802.11-based WMNs, the transmission with bandwidth assurance is facing rigorous challenges. In this paper, a novel joint design of multipath...
Adaptive cooperation with conflict-free relay assignment in a network setting is a challenging problem. The problem becomes even more difficult when users have quality-of-service (QoS) requirements but the available spectrum resource is limited, where admission control may be required. In this paper, we jointly study relay assignment and admission control in cooperative radio networks (CRNs). A one-stage...
Five service types with different priorities are defined to meet the QoS needs for different users, there are UGS, ertPS, rtPS, nrtPS, and BE on the IEEE 802.16 network. First, SS has to send connection request to BS before it is ready to transmit data. Then, SS can be allowed to transmit data white holding the allocated bandwidth from BS. Actually, BS utilizes CAC to identify whether enough bandwidth...
Two criteria are proposed to characterize and improve suboptimal coordinate-convex (c.c.) policies in Call Admission Control (CAC) problems with nonlinearly-constrained feasibility regions. Then, a structural property of the optimal c.c. policies is derived. This is expressed in terms of constraints on the relative positions of successive corner points.
In this paper we study quality-of-service (QoS) provisioning in an ad hoc cognitive radio network with spectrum underlay. Both streaming traffic and non-real-time (nrt) data traffic are considered. An admission control scheme is first proposed based on relatively static information such as path loss and average interference levels in order to guarantee the average throughput of each connection. Outage...
In this work we deal with Congestion Control (CC) strategies to protect the Quality of Service (QoS) of Real Time (RT) services in Orthogonal Frequency Division Multiple Access (OFDMA)-based and packet-switched networks such as Long Term Evolution (LTE) and Worldwide Interoperability for Microwave Access (WiMAX). Specifically, the first contribution of this paper is the adaptation of a CC strategy...
Admission control based on multiple criteria has always been a desirable feature for computer networks. In the past, we presented such a system, but it was based on a centralised decision mechanism, which by itself constitutes a significant limitation. Here, we describe a decentralised version of the initial admission control algorithm, while still keeping the multiple-criteria aspect, with each user...
Dynamic spectrum access is one of the most important premises of spectrum reuse based on cognitive radio technologies, which are considered to be the best way to alleviate the controversy on spectrum scarcity and low efficiency. However, most of previous work focuses on the increasing of system throughput, ignoring the QoS requirement of secondary users. In this paper, dynamic spectrum access with...
Proper admission control in cognitive radio networks is critical in providing QoS guarantees to secondary unlicensed users. In this paper, we study the admission control and channel allocation problem in overlay cognitive radio networks under the maximum cumulative delay constraint. We formulate it as a Markov decision process problem, and then solve it by transforming the original formulation into...
This paper introduces admission control policies for the IEEE 802.16 standard which aim to reach three main goals: restrict the number of simultaneous connections in the system so that the resources available to the scheduler are sufficient to guarantee the QoS requirements of each connection, support the service provider expectations by maximizing the revenue, and maximize the users satisfaction...
This paper proposes a novel admission control (AC) algorithm for guaranteed quality of service (QoS) to all users. The proposed solution provides better utilization of system capacity using adaptive modulation (AM). A scheduler based on a per user priority function is also given in this paper. The AC is given by allocating the exact number of slots for each user that will meet its QoS. For every new...
In this paper, an admission control (AC) scheme is proposed for handling multiclass Grade of Service (GoS) and Quality of Service (QoS) in Uplink Long Term Evolution (LTE) systems. GoS requirement in conjunction with QoS has been seldom taken into account in previous admission control and resource allocation algorithms for LTE uplink. We propose a novel algorithm for handling the priorities while...
Next generation wireless systems represent an heterogeneous environment encompassing different radio access network technologies (RATs) that differ in bandwidth, latency or cost. At the same time, mobile devices can now support multiple radio network interfaces and are therefore able to select from various available multiple heterogeneous access networks the most appropriate one in order to satisfy...
In this paper, we consider a femtocell deployment scenario in which radio resources are shared among self-organized femtocells. We propose a distributed Admission Control Mechanism (ACM) for traffic load balancing among sub-carriers when there are multiple Quality of Service (QoS) classes. Furthermore, we propose a mechanism based on Reinforcement Learning (RL) for slot allocation to the traffic streams...
Real time multimedia applications become an important part of Internet traffic and require a guaranteed quality of services. Call Admission Control (CAC) is a key element in the provision of guaranteed (QoS) in wireless networks. An adaptive algorithm is proposed in this paper. The QoS measures studied are new call blocking probability and handoff call probability. We describe and we compare several...
Admission control methods are important tools for ensuring the Quality of Service (QoS) of flows within a network by allowing additional flows only if their addition does not disrupt current flows. Two common admission control methods are Parameter-Based Admission Control (PBAC) and Measurement-Based Admission Control (MBAC). We have implemented versions of both methods in our Network QoS Management...
Underlay spectrum sharing in cognitive radio (CR) networks allows that the secondary user (SU) coexists with the primary user (PU) via primary spectrum sharing to the extent not to deteriorate the primary communication. It provides the SU with more access opportunity than the overlay one, but involves the risk that the quality of service (QoS) of the PU is degraded. In this context, controlling the...
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