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A Self-Adaptive QoS Guarantee Scheme for Multimedia Sensor Networks  [PDF]
Yan Sun,Huadong Ma,Liang Liu
International Journal of Distributed Sensor Networks , 2010, DOI: 10.1155/2010/316342
Abstract: In multimedia sensor networks, there may exist simultaneously two streams: end-to-end stream and event-to-sink stream. It brings a new set of challenges for QoS guarantees in multimedia transmission. In this paper, we first present a self-adaptive QoS guarantee scheme based on two-layer feedback. In transport layer, we partition network into 10 typical states and design a transport protocol, which makes the state transition to the optimal one. Moreover, we design a revenue structure of media stream to describe the relation between QoS and multimedia capturing approaches in the application layer, thus evaluating the optimal scheme of capturing multimedia according to multimedia packet generation ratio calculated by transport layer. A series of simulation experiments using NS2 are performed to demonstrate the effectiveness of our proposed scheme. 1. Introduction With the complexity of environment, conventional sensor networks [1], which are capable of collecting and processing simple scalar data such as temperature, humidity, or light, cannot provide users with complete and accurate knowledge to the monitored environment. It is desirable to introduce multimedia data (e.g., audio, video, and image) into environment monitoring activities in order to improve efficiency [2]. Motivated by this, multimedia sensor networks (MSNs) come into being. The characteristic of rich information, powerful capabilities, and flexible services doubtlessly make MSNs benefit from a plethora of data-hungry applications such as environment monitoring, traffic surveillance, security, and emergency response [3, 4]. Compared to conventional sensor networks, MSNs can provide more various service forms thanks to their capability of sensing and processing information-immense multimedia data. It is urgent to design effective QoS guarantee scheme to support flexible and reliable service for users. In general, MSNs have two kinds of basic service modes: event driven and query driven. ( ) Event Driven Service Mode ( Service). In this mode, multiple sensor nodes preprocess (e.g., compress, identify, and match) the raw environmental data then filter out and transmit valuable semantic data (called as data) to the sink node. ( ) Query-Driven Service Mode ( Service). In this mode, service request can always be initiated by users. MSNs respond to these service requests and return media stream (called as data) to users. The above two service modes have different transport models. Opposed to the traditional end-to-end transport model, the event-driven service mode uses event-to-sink transport
QoS Bandwidth Estimation Scheme for Delay Sensitive Applications in MANETs  [PDF]
Surjeet  , Arun Parkash, Rajeev Tripathi
Communications and Network (CN) , 2013, DOI: 10.4236/cn.2013.51001
Abstract:

For last few years, MobileAd hoc Networks (MANETs) have attracted a great interest in case of wireless and multimedia technologies. Infrastructure less nature of MANETs makes Quality of Service (QoS) provisioning very challenging and important research aspect. To find a QoS constrained route from source to destination, we should be able to effectively determine the available resources throughout the route. The routing protocol is the most integral part of any type of QoS provisioning. It has to decide which route is able to fulfill the requirement of the desired QoS for specified application. In this paper, modification has been proposed in the existing MANET protocols to get the information about total path bandwidth for delay sensitive applications. It uses modified technique for bandwidth estimation and for route maintenance. The proposed protocol is implemented and simulated using NS-2 simulator. Results of our implementation show that there is much improvement in overheads without any impact on overall end-to-end throughput.


An Adaptive Fair-Distributed Scheduling Algorithm to Guarantee QoS for Both VBR and CBR Video Traffics on IEEE 802.11e WLANs  [cached]
Saeid Montazeri,Mahmood Fathy,Reza Berangi
EURASIP Journal on Advances in Signal Processing , 2008, DOI: 10.1155/2008/264790
Abstract: Most of the centralized QoS mechanisms for WLAN MAC layer are only able to guarantee QoS parameters for CBR video traffic effectively. On the other hand, the existing distributed QoS mechanisms are only able to differentiate between various traffic streams without being able to guarantee QoS. This paper addresses these deficiencies by proposing a new distributed QoS scheme that guarantees QoS parameters such as delay and throughput for both CBR and VBR video traffics. The proposed scheme is also fair for all streams and it can adapt to the various conditions of the network. To achieve this, three fields are added to the RTS/CTS frames whose combination with the previously existing duration field of RTS/CTS frames guarantees the periodic fair adaptive access of a station to the channel. The performance of the proposed method has been evaluated with NS-2. The results showed that it outperforms IEEE 802.11e HCCA.
A Scalable MAC Protocol Supporting Simple Multimedia Traffic QoS in WSNs  [PDF]
JeongSeok On,HahnEarl Jeon,Jaiyong Lee
International Journal of Distributed Sensor Networks , 2011, DOI: 10.1155/2011/495127
Abstract: Wireless sensor networks (WSNs) are a vibrant research field for the last several years. Especially, design of MAC protocols supporting multimedia traffic QoS is recent challenging work. However, the mechanisms of protocols that can guarantee multimedia traffic QoS have several problems in multihop wireless sensor networks. There are a lot of reasons, including limited end-to-end delay and high throughput. In this paper, we propose ascalable MAC protocol that guarantees multimedia traffic, still images, and scalar sensor data QoS in multi-hop wireless sensor networks. The MAC protocol has made it possible to transmit multimedia streaming traffic without a great change of the end-to-end delay for a specific time. And if there are the some link failures in multi-hop transmission, the protocol can recover the links quickly. Using this algorithm, the proposed MAC protocol outperforms the IEEE 802.11e EDCF and the IEEE 802.15.4 MAC protocol in terms of the end-to-end delay and stable transmission of multimedia streaming data. 1. Introduction Social concern about applications using multimedia traffic has been growing for the last several years. Research papers concerning applications that generate multimedia traffic, namely, video and audio streaming, still images, and scalar sensor data, are being carried out to implement a communication protocol in the real world. These applications need mostly high throughput and low delay. Networks that connect wireless devices to obtain multimedia traffic are defined as wireless multimedia sensor networks (WMSNs) [1]. In WMSNs, MAC protocols supporting multimedia traffic QoS are divided into three types. The first is contention-based MAC protocols. The typical contention-based MAC protocol is IEEE 802.11e enhanced distributed coordination function (EDCF) that gives the differential priorities according to types of traffic. In EDCF protocol, nodes should participate in contention for channel acquisition through CSMA/CA technique. However, this scheme cannot guarantee multimedia traffic QoS, because the EDCF results in high collision rate at high multimedia traffic load. Most contention-based schemes [2, 3] cannot guarantee multimedia traffic QoS due to collisions of control packets. The second is time division multiple access (TDMA) MAC protocols. TDMA MAC protocols have been studied for supporting multimedia traffic QoS in WSNs. However, the centralized system is used to assign time slots in most TDMA MAC protocols. Due to the centralized system, TDMA MAC protocols [4] are not suitable in WMSNs in terms of the
User Profile Based Proportional Share Scheduling And Mac Protocol For Manets  [PDF]
Hannah Monisha . J,Rhymend Uthariaraj .V
International Journal of Distributed and Parallel Systems , 2012,
Abstract: Quality of Service(QoS) in Mobile Ad Hoc Networks (MANETs) though a challenge, becomes a necessity because of its applications in critical scenarios. Providing QoS for users belonging to various profiles and playing different roles, becomes the need of the hour. In this paper, we propose proportional share scheduling and MAC protocol (PS2-MAC) model. It classifies users based on their profile as High Profiled users (HP), Medium Profiled users (MP) and Low profiled users (LP) and assigns proportional weights. Service Differentiation for these three service classes is achieved through, rationed dequeuing algorithm, variable inter frame space, proportionate prioritized backoff timers and enhanced RTS/CTS control packets. Differentiated services is simulated in ns2 and results show that 9.5% control overhead is reduced in our proposed scheme than the existing scheme and results also justify that, differentiated services have been achieved for the different profiles of users with proportionate shares and thereby reducing starvation.
User profile based proportional share scheduling and mac protocol for manets  [PDF]
J. Hannah Monisha,V. Rhymend Uthariaraj
Computer Science , 2012, DOI: 10.5121/ijdps.2012.3123
Abstract: Quality of Service(QoS) in Mobile Ad Hoc Networks (MANETs) though a challenge, becomes a necessity because of its applications in critical scenarios. Providing QoS for users belonging to various profiles and playing different roles, becomes the need of the hour. In this paper, we propose proportional share scheduling and MAC protocol (PS2-MAC) model. It classifies users based on their profile as High Profiled users (HP), Medium Profiled users (MP) and Low profiled users (LP) and assigns proportional weights. Service Differentiation for these three service classes is achieved through, rationed dequeuing algorithm, variable inter frame space, proportionate prioritized backoff timers and enhanced RTS/CTS control packets. Differentiated services is simulated in ns2 and results show that 9.5% control overhead is reduced in our proposed scheme than the existing scheme and results also justify that, differentiated services have been achieved for the different profiles of users with proportionate shares and thereby reducing starvation.
An Energy Efficient MAC Protocol for QoS Provisioning in Cognitive Radio Ad Hoc Networks
S. M. Kamruzzaman,Md. Abdul Hamid,M. Abdullah-Al-Wadud
Radioengineering , 2010,
Abstract: The explosive growth in the use of real-time applications on mobile devices has resulted in new challenges to the design of medium access control (MAC) protocols for ad hoc networks. In this paper, we propose an energy efficient cognitive radio (CR) MAC protocol for QoS provisioning called ECRQ-MAC, which integrate the spectrum sensing at physical (PHY) layer and the channel-timeslots allocation at MAC layer. We consider the problem of providing QoS guarantee to CR users as well as to maintain the most efficient use of scarce bandwidth resources. The ECRQ-MAC protocol exploits the advantage of both multiple channels and TDMA, and achieves aggressive power savings by allowing CR users that are not involved in communication to go into sleep mode. The proposed ECRQ-MAC protocol allows CR users to identify and use the unused frequency spectrum of licensed band in a way that constrains the level of interference to the primary users (PUs). Our scheme improves network throughput significantly, especially when the network is highly congested. The simulation results show that our proposed protocol successfully exploits multiple channels and significantly improves network performance by using the licensed spectrum opportunistically and protects QoS provisioning over cognitive radio ad hoc networks.
Review of QoS mechanisms for mobile Ad Hoc networks
移动自组织网络服务质量控制机制综述

ZHANG Peng,CUI Yong,SUN Lei,
张鹏
,崔勇,孙磊

计算机应用 , 2009,
Abstract: There are difficulties to guarantee QoS of mobile Ad Hoc networks due to their features of dynamically changing topology and wireless communication. Current QoS techniques for mobile Ad Hoc networks are divided into five categories: link layer solutions, network layer solutions, transport layer solutions, cross layers solutions and cross networks solutions. The main link layer solutions are QoS MAC protocols. The main idea in network layer solutions is QoS routing. Wireless TCP is the main scheme to guarantee QoS in transport layer. To choose route and balance load, cross layer solutions were researched to provide network architectures to support QoS. The main idea in cross network solutions is to propose QoS solutions between mobile Ad Hoc networks and fixed networks. These QoS solutions were introduced and analyzed.
QoS Differentiation Based Adaptive p-Persistent MAC Scheme for Dynamic Optimization of the Channel Utilization
QoS区分的自适应p-Persistent MAC算法对信道利用率的动态优化

BAI Xiang,MAO Yu-Ming,LENG Su-Peng,MAO Jian-Bing,XIE Jun,
白翔
,毛玉明,冷甦鹏,毛建兵,谢军

软件学报 , 2009,
Abstract: This paper proposes an adaptive p-persistent MAC scheme, named QDA-MAC (QoS differentiation based adaptive MAC scheme), for WLAN to maximize the channel utilization and provide the service differentiation among different traffic stations. Specifically, different from the previous work, the proposed schemedoes not need to estimate the number of active stations for each priority class but still achieves the channelutilization close to its optimal value by exploiting a new parameter, persistent factor, whose optimal value candynamically follow the change of the load based on a simple estimation of the network status. At the same time, thetransmission probability of each priority class can be updated by the optimal persistent factor. Simulation andnumerical results show that QDA-MAC can achieve much higher channel utilization and have shorter delay thanstandard IEEE 802.11 DCF and IEEE 802.11e EDCA in all different WLAN environments.
A Novel Hierarchical Ant based QoS aware Intelligent Routing Scheme for MANETS  [PDF]
Debajit Sensarma,Koushik Majumder
Computer Science , 2013, DOI: 10.5121/ijcnc.2013.5614
Abstract: MANET is a collection of mobile devices with no centralized control and no pre-existing infrastructures. Due to the nodal mobility, supporting QoS during routing in this type of networks is a very challenging task. To tackle this type of overhead many routing algorithms with clustering approach have been proposed. Clustering is an effective method for resource management regarding network performance, routing protocol design, QoS etc. Most of the flat network architecture contains homogeneous capacity of nodes but in real time nodes are with heterogeneous capacity and transmission power. Hierarchical routing provides routing through this kind of heterogeneous nodes. Here, routes can be recorded hierarchically, across clusters to increase routing flexibility. Besides this, it increases scalability and robustness of routes. In this paper, a novel ant based QoS aware routing is proposed on a three level hierarchical cluster based topology in MANET which will be more scalable and efficient compared to flat architecture and will give better throughput.
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