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In next generation wireless systems, achieving seamless service continuity when transitioning between heterogeneous networks is a challenging task. An approach to optimize these handover procedures through the introduction of a standardized framework is followed by the IEEE 802.21 working group. The Media Independent Handover (MIH) function of IEEE 802.21 is mainly designed for "client-network"...
This paper compares QoE (Quality of Experience) of audio-video IP transmission with IEEE 802.11e EDCA and that with DCF in mobile ad hoc networks. We also assess QoE of the transmission with TXOP-bursting, which is an optional function of EDCA. QoE assessment of audio-video IP transmission in mobile ad hoc networks involves difficult issues. The wireless nodes can move, and then channel condition...
The focus of this paper is the IEEE 802.11e MAC layer modeling under slow time varying Rayleigh fading channel via both layered and multi-layered design approaches and through non Markovian Stochastic Petri Nets (NMSPN). In this paper, we carry out extensions to SPN IEEE 802.11 compact model reported in. Towards that, we investigate relaxation accounting for slow Rayleigh fading, service differentiation...
To satisfy the user requirements for continuous and real-time multimedia information, the concept of quality of service (QoS) has emerged as a main issue in mobile ad-hoc networks. QoS routing is to find a route according to the QoS requirements of the users. The provision of QoS guarantees is of utmost importance for the development of the multicast services. In this paper, we propose an efficient...
With the rapid development of mobile communication and the proliferation of mobile terminals, multimedia mobile business (MMB) is proposed and becomes a hot point of the research. 4G networks where the bandwidth wonpsilat be the transmission bottleneck will provide powerful support to MMB. As an important part of 4G, MANET is not capable of providing MMB because of the varying wireless channels, so...
The security of multimedia data in wireless ad hoc networks (WANet) is commonly provided by encryption, i.e., the mathematical process that transforms a plaintext message into unintelligible ciphertext. Nevertheless, the classical and modern ciphers have all been developed without taking into consideration the intrinsic characteristics of multimedia flows. Our approach aims to reduce the computational...
In wireless mobile peer-to-peer (P2P) networks, multiple sources can provide multimedia file sharing at the same time. The selection of multiple sources is one of the key issues in the design of a multi-source transmission system in wireless mobile P2P networks. In this paper, we propose a distributed multi-source sender selection scheme to maximize the receiving data rate and minimize the energy...
As a TCP-Friendly Rate Control protocol on the basis of TCP Reno's throughput equation, TFRC is designed to provide optimal service for unicast multimedia delivery over the wired Internet networks. However, when used in wireless environment, it suffers significant performance degradation. Most of the current research on this issue only focuses on the TFRC protocol itself, ignoring tightly-coupled...
Wireless mesh networks (WMNs) have the potentialities to greatly penetrate the marketplace in the next decade. They can be considered a hybrid between wireless infrastructure and ad-hoc networks; no other network infrastructure is needed other than the mesh points, thus providing flexibility in building and expanding the network, allowing for automatic discovery of neighboring nodes, increased reliability...
In ad-hoc networks, the video quality of real-time services is greatly decreased when bandwidth reduction and channel access delay occur. In this paper, a dynamic frame rate adjustment of video transmissions is proposed in case of network congestion. Simulation results show that our approach improves the quality of real-time video over IEEE 802.11 based vehicular networks by guaranteeing a better...
Multiple description coding (MDC) has been proposed as a source coding technique that is robust to channel errors for video transmission. MDC generates multiple independent bit-streams, where the multiple bit-streams are referred to as multiple descriptions (MD). Furthermore, it enables a useful reproduction of the signal when any description is received correctly. This paper proposes a new multicast...
The following topics are dealt with: OFDM/MIMO; multimedia networking and broadband access; traffic modeling and analysis; network design and localization; radio resource management and QoS provisioning; wireless networks; ad hoc networks; hardware design and coding; network security and cognitive radios; sensor networks.
Bandwidth reservation in mobile wireless networks is a very challenging task due to the instability of radio channels, node mobility and lack of coordination between mobile nodes. Previously proposed reservation MAC protocols reserve a slot to each real-time source assuming that the source will use the reserved slot in each super-frame. Since different applications may have different bandwidth requirements,...
Recently, multimedia becomes increasingly popular for the users of ad hoc networks. To support multimedia and real-time application the study of QoS issues in MANETs is essential. MANETs can provide efficiently multimedia users with the required mobility. Development in multimedia and ad hoc networking has spurred rapidly growing research interested in multimedia delivery over ad hoc networks. Designing...
As the rapid growth of multimedia communication demand, it is inevitable to develop a method that could convey multimedia applications on IP network that is previously a text-based communication. In this research, we implement and investigate the H.264 and MPEG-4 video codec, as well as the quality of their transport over wireless environment, particularly mobile IPv4 and adhoc networks. Video quality...
The following topics are dealt with: mobile ad hoc networks; wireless sensor networks; routing and wavelength assignment; physical layers techniques; traffic engineering; traffic routing; peer to peer computing; multimedia communication; Internet services; quality of service; wireless network cooperation; wireless network cognition; optical burst switching; and optical packet switching.
This paper presents the issues related to efficient transmission of encoded video (such as H.264) over wireless links using the TFRC protocol. It proposes a novel mechanism that utilizes cross-layer approaches for adaptation of the power transmission level of the sender and feedback information regarding the wireless connection status from the receiver for improved transmission statistics and therefore...
Routing, the act of moving information across an Internet work from a source to a destination is one of the major issues in computer network literature. When it comes to mobile ad hoc network, the complexity increases due to various characteristics like dynamic topology, absence of centralized authority, time varying QoS requirements etc. The biggest challenge in this kind of networks is to find a...
Routing is a challenging task in mobile adhoc network due to nodal mobility, unstable links and limited resources. Swarm intelligence, as demonstrated by biological swarm, such as ant colony has found to be a attractive technique for routing in MANET. However existing swarm intelligence based routing protocols find an optimal path by considering only one or two route selection metrics, such as hop...
This paper introduces a combined geographic and a Media Access Control (MAC) protocol for mesh, ad-hoc and cognitive networks. For mesh and ad-hoc networks, this paper examines the end-to-end (source to destination) link performance characteristics when supporting multimedia traffic. This paper also explains the cognitive network concept prior to analyzing cognitive network related results. The performance...
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