For efficient spectrum utilization in cognitive radio networks it requires appropriate allocation of idle frequency spectrum among coexisting cognitive radios while maximizing total bandwidth utilization and minimizing interference. The fixed spectrum allocation scheme leads to low spectrum utilization across the whole spectrum. This paper is an attempt to overcome the problem in such wireless ...

The transportation of compressed video data without loss of picture quality requires the network to support large fluctuations in bandwidth requirements. These fluctuations can be smoothed, but straightforward approaches to smoothing can still suffer from excessive buffering requirements, poor buffer utilization, and an excessive number of bandwidth changes. This paper introduces critical bandw...

This paper describes two traffic engineering techniques for implementing proportional differentiated services based on Multiprotocol Label Switching constraint based routing. Both use a dynamic bandwidth allocation scheme to modify the bandwidth reserved by each traffic class according to the current network load. The first scheme uses an adaptive algorithm that qualitatively determines the req...

Broadband satellite communication networks operating at Ka band (20-30 GHz) play a very important role in today’s worldwide telecommunication infrastructure. The problem, however, is that rain can be the most dominant impairment factor for radio propagation in these frequency bands. Allocating frequency bandwidth based on the worst-case rain fading leads to the waste of the frequency spectrum d...

This paper gives an overview of current work and research conducted on passive optical networks, namely on dynamic bandwidth allocation and providing quality of service guarantees. The main areas of interest for investigating dynamic bandwidth allocation are grant sizing, grant scheduling and optical network unit queue scheduling. Regarding quality of service parameters bandwidth, delay and jit...

The paper deals with the problem of resource allocation in a substrate network with DaVinci architecture. We present a methodology of decision making on network bandwidth allocation based on fuzzification and defuzzification principles and the expert knowledge database of fuzzy rules and we describe a fuzzy logic based modification of the adaptive bandwidth allocation mechanism to optimize deci...

The circle travelling delay between OLT (Optical Line Terminal) and ONU (Optical Network Unit) is one of most important items in dynamic bandwidth allocation (DBA) algorithms in PON, called RTT (Round Trip Time). The RTT is taken into account when OLT assigns the start times for upstream bandwidth grants. In most case, RTT is estimated before making bandwidth allocation decisions in dynamic ban...

Data stream providers face a hard decision to satisfy the requirements of their subscribers. Each user has a minimum and a maximum required bandwidth. The server should be able to decide which requests can be satisfi ed and how much bandwidth will be allocated to each. We present a theoretical framework in a distributed mechanism for fair bandwidth allocation on a network with various bottlenec...

A wireless network consists of a set of wireless nodes forming the network. The bandwidth allocation scheme used in wireless networks should automatically adapt to the network’s environments, where issues such as mobility are highly variable. This paper proposes a method to distribute the bandwidth for wireless network nodes depending on dynamic methodology;this methodology uses intelligent clu...

Problem statement: WiMAX supports multiple types of traffic such as data, voice and video. Each flow requires a certain minimum bandwidth to achieve its QoS. Bandwidth allocation to traffic classes should be in such a way that fairness criteria is met with. Hence, we propose a dynamic bandwidth allocation mechanism to achieve fair and efficient allocation. Approach: We present a Generalized Sto...