Cross-layer Adaptation Research Articles

An Adaptive Cross-Layer Architecture to Optimize QoS Provisioning in MANET

<p>Mobile Ad Hoc Network (MANET) is a collection of mobile nodes, which dynamically form a temporary network, without using any infrastructure like wireless access points or base-stations. The provision of QoS guarantees is much more challenging in Mobile Ad hoc Networks. There are many interesting applications such as multimedia services, disaster recovery etc can be supported if Quality-of-Service (QoS) support can be provided for MANETs. But QoS provisioning in MANETs is a very challenging problem when compared to wired IP networks. This is because of unpredictable node mobility, wireless multi-hop communication, contention for wireless channel access, limited battery power and range of mobile devices as well as the absence of a central coordination authority. So, the design of an efficient and reliable routing scheme providing QoS support for such applications is a difficult task. In this paper we studied the challenges and approaches for QoS aware routing techniques. </p><p> </p>

AMCCR: Adaptive Multi-QoS Cross-Layer Cooperative Routing in Ad Hoc Networks

The cooperative communication technique in an ad hoc network exploits the spatial diversity gains inherent in multiuser systems and mitigates the multipath fading. This technique is necessary but perhaps not sufficient to meet the QoS demands in ad hoc network. This is due to the fact that routing protocol at the network layer is more responsible for the successful packet delivery and QoS support. In this paper, we propose an adaptive multi-QoS cross-layer cooperative routing (AMCCR) protocol that enhances the performance through the cooperation of physical, MAC, and network layers. We first formulate an approach to analyze the channel state variations for effective communication schemes at the physical layer. Secondly, we dynamically select the transmission mode to employ cooperative MAC scheme by exploiting spatial diversity. Thereafter, the network layer chooses an optimized route from source to destination through the selected best relay candidates based on multiple QoS metrics. The paper is further extended to support dual-hop half-duplex communication via selected relay by coding technique. The proposed protocol is validated by extensive simulations and compared with CD-MAC and CODE protocols. The results clearly show that the proposed cooperative cross-layer design approach significantly improves the average delay, throughput, and network lifetime of the system.

Adaptive Cross Layer Design for Mobility Using Media Independent Handover

The fading boundaries between wireless computer networks and mobile personal communication have lead to rapid growth in all fields of mobile communication which include deployment of communication system, advances in mobile techniques and services in heterogeneous network environment. Various layers of the protocol stack contribute in decision-making during network switching in such an environment. Various network and quality of service metric considered in proposed framework include flow rate (congestion measure), throughput, delay, jitter and packet loss. Thus, the proposed framework is a unified and global cross layer framework to overcome challenging problem of seamless access of wireless networks and services. Inter-layer and inter-network communication is implemented through IEEE 802.21 Media Independent Handover standard.

SDN Orchestration for Next Generation Inter-Networking: A Multipath Forwarding Approach

Increasing trend of peering at Internet exchange points (IXPs) provides a topological and network management advantage to the Internet service providers (ISPs) that is otherwise not possible through individual peering arrangements with their neighboring domains. ISPs keep analyzing potential advantages to peer at geographically diversified IXPs. Increasing degree of multihoming in ISPs requires extensive coordination among ISPs in different roles (access and transit), for mutual benefit. We propose a novel approach to build a conducive inter-networking ambiance for future data centric applications. Our approach exploits edge multiplicity of transit ISPs present across different IXPs to leverage a cross layer coordination between network stack at access ISP subscribers and the network infrastructure. Software defined networking provides a useful apparatus to control IXP fabric and also empowers our multipath forwarding strategy for an optimal network resource utilization in the inter-domain configuration. Contributions of this paper include the derivation of abstracted overlay graph from an IXP centric inter-domain connectivity model. This graph is used to provide multipath forwarding for increased reliability and throughput over abstracted graph. Adaptive cross layer coordination increases the efficiency of the proposed framework and provides an online mechanism of forwarding the traffic across the domains. We have observed as high as 54% increase in throughput using proposed scheme as compared with single path routing and forwarding strategy currently employed at the Internet backbone.

Content and Network Adaptive Cross-layer Optimization for Video Transmission

Content and Network Adaptive Cross-layer Optimization for Video Transmission

Energy Aware and Adaptive Cross-Layer Scheme for Video Transmission Over Wireless Sensor Networks

Wireless multimedia sensor networks (WMSNs), is an ad hoc network of wirelessly connected sensor nodes that allow retrieving video and audio streams, still images, and scalar sensor data but such sensors are limited in energy, memory, communication, and computational power. Multimedia transmission over wireless sensor network (WSN) is a challenging task due to quality-of-service(QoS) guarantees such as huge amount of bandwidth, strict delay, and lower loss ratio. Recently, cross-layer approach adopted by WMSNs shows a promising approach that improves quality of multimedia transmitted over WSNs under different wireless conditions. In this paper, an energy aware and adaptive cross layer scheme to transmit multimedia content over WSNs is presented. It provides packet, queue, and path scheduling, so that it selects optimal video encoding parameters at application layer according to current wireless channel state, and schedules packets according to its type through an adaptive priority video queue so that less important packets are dropped in case of network congestion. Finally, path scheduling is introduced so that different packets types/priority are routed through different paths with different QoSs considering network lifetime. Simulation results show that new scheme transmits video over WSNs efficiently and meets QoS requirements and uses energy wisely to prolongs network lifetime.

Multiple Video Delivery in m-Health Emergency Applications

M-health services are expected to become increasingly relevant in the management of emergency situations by enabling real-time support of remote medical experts. In this context, the transmission of multiple health-related video streams from an ambulance to a remote hospital can improve the efficacy of the teleconsultation service, but requires a large bandwidth to meet the desired quality, not always guaranteed by the mobile network. In order to deliver the multiple streams over a single bandwidth-limited wireless access channel, in this paper we propose a novel optimization framework that enables to classify the available video sources and to automatically select and adapt the best streams to transmit. The camera ranking algorithm jointly works with a cross-layer adaptation strategy for multiple scalable streams to achieve different objectives and/or tradeoffs in terms of number and target quality of the transmitted videos. The final goal of the optimization is to dynamically adjust the overall transmitted throughput to meet the actual available bandwidth, while being able to provide high quality to diagnostic video sequences and lower quality to less critical ambient videos. Numerical simulations considering a realistic emergency scenario with long term evolution advanced (LTE-A) connectivity show that the proposed content/context-aware solution is able to automatically select the best sources of information from a visual point of view and to achieve optimal end-to-end video quality for both the diagnostic and the ambient videos.

Location aware sensor routing protocol for mobile wireless sensor networks

Location aware sensor routing (LASeR) protocol is a novel solution to the challenges of routing in mobile wireless sensor networks (MWSNs). It addresses the high reliability and low latency requirements of emerging applications. The protocol uses location information to maintain a gradient field even in highly mobile environments, whilst reducing the routing overhead. This allows the protocol to utilise a blind forwarding technique to propagate packets towards the sink. The protocol inherently utilises multiple paths simultaneously to create route diversity and increase its robustness. LASeR is designed for use in a high variety of MWSN applications with autonomous land, sea or air vehicles. Analytical expressions are derived and evaluated against the simulations. Extensive modelling and simulation of the proposed routing protocol has shown it to be highly adaptable and robust. It is compared with the recent MWSN proactive highly ambulatory sensor routing protocol, the high performance mobility adaptive cross-layer routing protocol, as well as ad-hoc on-demand distance vector and optimised link state routing. Protocols are evaluated on packet delivery ratio, end-to-end delay, overhead, throughput and energy consumption. The results highlight both the high performance of LASeR in various challenging environments and its superiority over the state-of-the-art.

Cloud-assisted QoE guarantee scheme based on adaptive cross-layer perceptron of artificial neural network for mobile Internet

For improving the system performance of mobile Internet, how to provide the Quality of Experience (QoE) guarantee is an important factor. First, based on artificial neural network and adaptive cross-layer perceptron, we studied the cloud-assisted QoE guarantee mechanism. Then, according to the power, we divided the distance and perceptron layers of mobile Internet and cloud into three levels. We showed the state information definition of the mobile node on the basis of the adaptive adjustment perceptron layers. Thirdly, the perceptron network topology would be updated according to the customer service, which would be updated based on the perceptron learning rule for improving the training practice efficiency. The above scheme would guarantee the QoE effectively. The experimental results show that the proposed QoE guarantee mechanism has obvious advantages in terms of throughput, efficiency, and reliability.

Adaptive Cross-Layer Multipath Routing Protocol for Mobile Ad Hoc Networks

Mobile ad hoc networks (MANETs) are generally created for temporary scenarios. In such scenarios, where nodes are in mobility, efficient routing is a challenging task. In this paper, we propose an adaptive and cross-layer multipath routing protocol for such changing scenarios. Our routing mechanisms operate keeping in view the type of applications. For simple applications, the proposed protocol is inspired from traditional on-demand routing protocols by searching shortest routes from source to destination using default parameters. In case of multimedia applications, the proposed mechanism considers such routes which are capable of providing more data rates having less packet loss ratio. For those applications which need security, the proposed mechanism searches such routes which are more secure in nature as compared to others. Cross-layer methodology is used in proposed routing scheme so as to exchange different parameters across the protocol stack for better decision-making at network layer. Our approach is efficient and fault tolerant in a variety of scenarios that we simulated and tested.

Cross-layer TCP/IP segmentation, re-routing and adaptive modulation techniques to exploit instantaneous BER variations on parallel subchannels

This paper describes a cross-layer technique for TCP-enabled multichannel wireless communications systems such as Multiple-Input Multiple-Output (MIMO) links. The technique uses adaptive modulation (AM) and different packet re-routing strategies over physically decomposed sub-channels to exploit time-varying channel conditions. The paper will demonstrate that combining both AM and packet re-routing mechanisms can improve the overall performance of MIMO systems where sub-channels possess unbalanced or uneven time-varying error rate characteristics. A simulated wireless communications system is developed to evaluate packet re-routing techniques over four sub-channel connections made available to the link layer. It then considers the effect of cross-layer link modulation adaptation switching. The system is investigated primarily in terms of goodput for several channel arrangements and characteristics, for various data rates and mean bit error rates. Based on the investigation results, this paper will demonstrate that even simple re-routing and AM mechanisms may be beneficial for systems utilising multiple antennas, as long as these expose the underlying sub-channels and their different instantaneous error characteristics to the link layer.

English

English

Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

ACWSN: an adaptive cross layer framework for video transmission over wireless sensor networks

Wireless multimedia sensor networks (WMSNs), have limited resources in terms of computational, memory, bandwidth, and battery capability, which makes transmitting multimedia content over it, is a challenge as multimedia requires QoS guarantee. Recently adopting cross-layer design in WMSNs proved to be a promising approach, which improves quality of service of WSN under various operational conditions. In this work, an adaptive cross layer framework for transmitting multimedia content over WSN (ACWSN) is presented, it is based on an extensive study of Group Of Picture structure effect on quality of multimedia transmission in various wireless channel states that is executed at sink node. It adaptably selects optimum video encoding parameters at application layer according to current wireless channel state which is communicated from physical layer and recommendations communicated from sink node; in addition an AVQ (adaptive video queue) which schedule packets according to its type to drop less important packets in case of network congestion. Simulation results show that ACWSN optimizes video quality in different wireless channel conditions.

Energy-Aware and Adaptive Cross Layer Framework for Video Transmission over Wireless Sensor Networks

Wireless Multimedia Sensor Networks (WMSNs), is a network of sensors which are limited in terms of computational, memory, bandwidth, and battery capability. Multimedia transmission over WSN requires certain Qos guarantees such as huge amount of bandwidth, strict delay and lower loss ratio, which makes transmitting multimedia content over it, is a challenging problem. Recently adopting cross-layer design in WMSNs proved to be a promising approach, which improves quality of service of WSN under various operational conditions. In this work, an energy aware framework for transmitting multimedia content over WSN (ECWMSN) is presented, where packet and path scheduling were introduced, so that It adaptably selects optimum video encoding parameters at application layer according to current wireless channel state, and schedules packets according to its type to drop less important packets in case of network congestion. Finally, path scheduling is introduced so that different packets types/priority is routed through suitable path with suitable Qos taking into consideration the network lifetime. Simulation results show that ECWMSN optimizes video quality and prolongs network lifetime.

Analytical model in discrete time for cross-layer video communication over LTE

Since video traffic is resource intensive, it is a challenging issue to stream video over low bandwidth networks, whereas video communication over LTE becomes an open research topic nowadays due to LTE’s high throughput capabilities. Indeed, video transmission requires low delay, and wireless channel is time-varying, which result in a scenario when a layer-separated design is replaced by a Cross-Layer Adaptation (CLA) principle. In this paper an efficient analytical model that evaluates the behavior of the downlink LTE channel with CLA is presented. To the best of our knowledge, this is the first time an analytical model using CLA principle has been devised that covers both the transmission process from the eNB to the User Equipment (UE) at the first phase and video decoding process at the UE at the second phase. In order to ensure the cross-layer adaptation in the model, the arrival rate varies based on the received video request, whereas the service probability changes according to the channel quality indicator sent from the UE. In the experimental part the analysis of the main performance measures found from the stationary distribution is conducted.

Spectrum efficient cross-layer adaptation of Raptor codes for video multicasting over mobile broadband networks

This paper explores the use of rateless application layer Forward Error Correction (AL-FEC) based on Raptor codes in a spectrally efficient way for real-time video multicasting over mobile broadband networks. The link between channel errors at the PHY, MAC and application layers and the required Raptor code parameters for quasi-error free video transmission is investigated. Low Raptor code rates are shown to place high demands on the limited bandwidth of a wireless channel. The selection of Modulation and Coding Scheme (MCS) is extended to take into account the channel resources required to accommodate the additional Raptor overheads. A cross-layer optimization approach and a novel metric are proposed to select the Raptor code parameters and the MCS mode jointly to maximize wireless transmission efficiency. Simulation results show that 166% more bandwidth is required by a non-Raptor enabled multicast WiMAX system, assuming a Mobile Station (MS) speed of 10 km/h, in comparison to the optimized Raptor AL-FEC multicast WiMAX system. Results show that more bandwidth is required at lower MS speeds. Furthermore, the optimized Raptor AL-FEC system is shown to eliminate packet loss, to enhance the link budget by up to 6 dB, which quadruples multicast coverage in LoS locations, and to increase the total goodput by 67%, in comparison to a non-Raptor enabled multicast WiMAX system.

Cross-Layer Framework for Multiuser Real Time H.264/AVC Video Encoding and Transmission over Block Fading MIMO Channels Using Outage Probability

We present a framework for cross-layer optimized real time multiuser encoding of video using a single layer H.264/AVC and transmission over MIMO wireless channels. In the proposed cross-layer adaptation, the channel of every user is characterized by the probability density function of its channel mutual information and the performance of the H.264/AVC encoder is modeled by a rate distortion model that takes into account the channel errors. These models are used during the resource allocation of the available slots in a TDMA MIMO communication system with capacity achieving channel codes. This framework allows for adaptation to the statistics of the wireless channel and to the available resources in the system and utilization of the multiuser diversity of the transmitted video sequences. We show the effectiveness of the proposed framework for video transmission over Rayleigh MIMO block fading channels, when channel distribution information is available at the transmitter.

A Cross-Layer QoE-Based Approach for Event-Based Multi-Tier Wireless Multimedia Sensor Networks

Wireless Multimedia Sensor Networks (WMSNs) are attracting attention from both academic and industrial environments due to the rapid development of low-cost multimedia sensors. With the enhancement of the multimedia content captured by multimedia devices, WMSNs play an important role in pervasive and ubiquitous systems. The multimedia content in these networks has the potential to enhance the level of collected information, by enlarging the range of coverage, and enabling multi-view support. In the case of WMSN applications, the multi-tier network architecture has proved to be more beneficial than single-tier architecture in terms of energy-efficiency, scalability, functionality and reliability. In this context, a multimedia event detection application is a promising application for multi-tier WMSNs, where the lower-tier nodes detect an event occurrence by means of scalar measurements, and the higher-tier nodes will be woken up to send real-time video flows from the event area. The transmission of multimedia content requires a certain quality level from the user's perspective, while energy consumption and network overhead should be minimized. Among the existing mechanisms for improving video transmissions, application-level Forward Error Correction (FEC) is regarded as a suitable solution to improve video quality level from the user´s standpoint. In this work, the authors propose an adaptive cross-layer approach, which includes a Quality of Experience (QoE)-aware FEC mechanism for WMSNs by generating redundant packets, based on frame importance from user's experience. Additionally, the aothors introduce a multi-tier routing protocol to select the best route to transmit multimedia data. According to the simulation results, the proposed cross-layer approach achieved high video quality level with reduced transmission of redundant packets, which will bring many benefits to a resource-constrained system.

Security in cognitive radio networks [Guest Editorial

Cognitive radio (CR) is an emerging advanced radio technology in wireless access, with many promising benefits including dynamic spectrum sharing, robust cross-layer adaptation, and collaborative networking. Based on software-defined radio (SDR), CRs are fully programmable, and can sense their environment and dynamically adapt their transmission frequencies, power levels, modulation schemes, and networking protocols for improving network and application performance. It is anticipated that CR technology will be the next wave of innovation in information and communications technologies.