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We focus on a new class of home networking applications that enable wireless communication between multimedia devices using the WiMedia MAC protocol. Applications like streaming video from DVD players to HDTVs, generate high data rates and can easily saturate the bandwidth even at the rates provided by UWB transmissions. Thus we need to enhance the MAC layer to improve bandwidth utilization and efficiently...
Efficient operation of a cognitive personal area network (CPAN) may be achieved if each data transmission is taxed by requiring the transmitting node to participate in cooperative sensing for a prescribed time period. We investigate the data transmission performance of this approach as well as its sensing accuracy. Through adaptive management of both the sensing process and data transmission, we show...
Heterogeneous wireless network (HWN) technology enables a mobile client (MC) to access multiple heterogeneous subnets for better quality of service (QoS) at a lower cost. In the context of conventional network protocol, we cannot fully utilize the potential of a HWN by having separate and independently operating subnet interfaces. In this paper, we propose a multi-MAC management scheme, performing...
Polling schemes in the IEEE 802 MAC layer provide some QoS support for multimedia applications above what can be provided with the contention scheme. However, in highly loaded environments, reliability and efficiency remain the main challenges for current detailed polling schemes. In this paper, we present a detailed analysis of polling medium access, and propose a novel mechanism, the Registered...
The high end-user data rates provided by HSDPA makes it a realistic alternative of wired Internet access. New 3GPP releases and the migration to packet based transport are further improving the capabilities of HSDPA. As a result, mobile data traffic is continuously increasing, various packet based services and applications with different QoS requirements are now accessible through HSDPA systems. This...
In this paper we analyzed the principle of an Adaptive Random-Reservation Medium Access Control (MAC) protocol in Sat-ATM Network which can support almost all ATM service classes, emphasizes the adaptive random-reservation MAC protocol with its performance evaluated through simulation. The result indicates that the TDMA based Adaptive Random-Reservation MAC protocol can maximize the utilization of...
Industrial networks based on IEEE 802.15.4 are spreading, even though the joint requirement on predictability and reliability from industrial applications is hard to fulfil in wireless networks, and the data rate of IEEE 802.15.4 is rather low. With the goal of providing real-time guarantees, with increased reliability and throughput, we propose two multichannel network architectures based on IEEE...
In this paper, we propose a new 802.16 Qos scheduling architecture based on GPSS, integrating some kinds of existing scheduling algorithms. Then we design a simulation experiment to validate the effectiveness of the Qos scheduling architecture using Anylogic. The simulation results prove the new QoS architecture is effective, which can not only meet the delay requirement of real time applications,...
The IEEE 802.16 is a well known set of standards, which have been developed for global deployment of Metropolitan Area Networks (MANs) in order to provide broadband wireless accesses supporting the integrated transmission of multimedia applications with different Quality of Service (QoS) requirements. In order to achieve the QoS requirements of multimedia applications, the IEEE 802.16 standards offers...
In this paper we investigate performance of enhanced medium access control (MAC) protocol of the IEEE 802.16e standard (mobile WiMAX). We consider the multipoint-to-multipoint (MPMP) mode MAC because it allows organization of fully mesh and more flexible networks then point-to-multipoint mode (PMP). Enhanced WiMAX features are useful for building a low-cost broadband telecom infrastructure in BRIC...
This paper evaluates the major MAC enhancement of IEEE 802.11n to realize high throughput, i.e. frame aggregation. In contrast to existing studies of this enhancement, we analyze the efficiency instead of the mere performance. The results show significant efficiency improvement by frame aggregation. Furthermore, the efficiency analysis leads to important conclusions for system configuration and adaptation...
To enable ubiquitous end-to-end quality of service over IP networks expanding to rural areas, we examine resource allocation problems of a MAC layer for an OFDM MIMO wireless base station (BS) using multiuser beamforming. We compare two linear beamforming techniques, zero-forcing (ZF-BF) and minimum mean square error (MMSE-BF). To guarantee minimum bandwidth and low packet delay in an environment...
WDM optical packet rings are a promising candidate for next generation metropolitan area networks (MAN), which are expected to support an increasing amount of traffic coming from a variety of applications and services (e.g., video on demand, video broadcasting, IP telephony). In this paper, we focus on multi-token WDM rings, where for each wavelength channel a special control packet, i.e., the token,...
Recently, the necessity of applications where many users have to interact in a close manner over mobile Ad-Hoc networks gains high popularity. Multicast communication is essential in this type of applications to reduce the overhead of group communication. For group-oriented multimedia applications Quality of Service (QoS) provision is a basic requirement, which makes an efficient QoS multicast routing...
The IEEE 802.16-2004 standard defines a medium access control (MAC) layer for a mesh network topology. In these networks, wide scale power outages can cause serious disruptions to digital services when centralized scheduling is used. This results in very long service recovery times for all mesh nodes. In this paper we propose a new recovery scheme and study the performance of the initialization process...
The WiMedia Ultra-Wide Band (UWB) specifications include physical layer and distributed Medium Access Control (MAC) layer. Physical layer offers a range of coded data rates from 53.3 Mb/s to 480 Mb/s. WiMedia MAC consists of Beacon period (BP), Distributed Reservation Protocol (DRP) and Prioritized Contention Access (PCA). DRP allows access to the medium through reservation, while PCA provides access...
With the extensive application of networks, access network is receiving wide attention as it connects user terminals and the core network. The QoS issue in the process of data transmission is particularly concerned by both terminal users and network administrators. WiMax, a new popular access technology, has defined perfect QoS mechanism at the MAC layer. However, bandwidth allocation scheduling algorithm,...
Medium Access Control (MAC) protocols for WDM Ethernet passive optical networks (WDM-EPONs) suffer from low performance when the users' round trip times are different. In this paper a new MAC protocol for WDM-EPONs is introduced which overcomes the above limitation by filling the gaps in the scheduling program. Moreover, the proposed scheme favors the requests that present a burst-like behavior, by...
Home appliances can be connected in a ubiquitous manner by communication networks. In addition to the operation sensing of home appliances, appliance management via sending control messages will be needed. The control operations include power adjustment of home appliances and sampling rate change of a sensing device. It should be noted that control messages differ from sensing data and the former...
The IEEE 802.16 Working Group on Broadband Wireless Access is developing the standard for broadband wireless access networks in Metropolitan Area Network (MAN), also know as WiMAX. One of the features of the 802.16 MAC layer is that it is designed to differentiate service among traffic categories with different multimedia requirements. Based on these assumptions and considering that the standard does...
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