Multi Hop Wireless Networks

Multi-hop Wireless Networks (MWNs) emerge as an enabling communication technology, evolving rapidly due to the accelerating advancements and creating potential network applications that significantly improve the quality of life. Pure general-purpose MANET laid the theoretical foundation for MWNs, and many extensions are successfully deployed in commercial networks. This article surveys geographical routing protocols and mobility models applicable to MWNs and their recently proposed extensions. Mobility is a significant factor that profoundly impacts the performance of multi-hop geographical routing. This study analyzes various mobility models that significantly influence the performance of geographical routing protocols based on the characteristics and behavior of various network extensions. This survey investigates the primary challenges in designing geographical routing for various mobility models that notably impact the routing performance for a particular network extension. It also explores the enormous potential of geographical routing protocols under each extension and adequately addressing the routing and mobility-related issues. The essential factors that impact geographical routing, the freshness of location information, and the adaptive location update are examined extensively for various network extensions. Finally, the survey concludes with future research challenges and directions.

In this article it has presented leach extended hierarchical 3-level clustered heterogeneous and dynamics algorithm. On suggested protocol (LEH3LA) with planning of selected auction cluster head, and alternative cluster head node, problem of delay on processing, processing of selecting members, decrease of expenses, and energy consumption, decrease of sending message, and receiving messages inside the clusters, selecting of cluster heads in large sensor networks were solved. This algorithm uses hierarchical heterogeneous network (3-levels), collective intelligence, and intra-cluster interaction for communications. Also it will solve the problems of sending data in Multi-BS mobile networks, expanding inter-cluster networks, overlap cluster, genesis orphan nodes, boundary change dynamically clusters, using backbone networks, cloud sensor. Using sleep/wake scheduling algorithm or TDMA-schedule alternative cluster head node provides redundancy, and fault tolerance. Local processing in cluster head nodes, and alternative cluster head, intra-cluster and inter-cluster communications such as Multi-HOP cause increase on processing speed, and sending data intra-cluster and inter-cluster. Decrease of overhead network, and increase the load balancing among cluster heads. Using encapsulation of data method, by cluster head nodes, energy consumption decrease during sending data. Also by improving quality of service (QoS) in CBRP, LEACH, 802.15.4, decrease of energy consumption in sensors, cluster heads and alternative cluster head nodes, cause increase on lift time of sensor networks.

Nodes in a dynamic wireless network are expected to autonomously self-organize and configure routes for communicating amongst themselves. Such networks have applications in several scenarios, including military, disaster relief, and search and rescue operations. Designing a solution for such networks is challenging because of their unique characteristics. Traditionally, decentralized solutions have been sought-after. In the past few years, Software-Defined Networking (SDN) has emerged as a promising approach for designing effective solutions for different types of networks. In this paper, we present an SDN-based architecture and a control communication protocol for dynamic multi-hop wireless infrastructure-less networks. In particular, the solution is designed for networks with 1) node mobility and unreliable con-nectivity, 2) unstructured network topology, 3) limited bandwidth and high interference due to multi-hop communication in a shared channel, 4) no out-of-band communication channel, and 5) no location-tracking services for learning the position of mobile nodes. We evaluate our architecture and control communication protocol in NS-3 and compare the results with two conventional solutions-OLSR and DSDV. The results demonstrate up to 40% reduction in the routing overhead while achieving the same or better throughput than the conventional solutions for networks of size up to 50 nodes.

In this paper, we have proposed a Relay based Improved Throughput and Energy-efficient Multi-hop Routing Protocol (Rb-IEMRP) for the Intra Wireless Body Sensor Network (Intra-WBSN). Moreover, mathematical analysis has been presented, to calculate the minimum number of relay nodes require to be deployed corresponding to the bio-sensor nodes in Intra-WBSN. Normal sensing data from bio-sensor nodes forwarded to BNC through relay nodes while emergency data is directly transmitted to BNC. Relays nodes are placed in the patients' cloth. It can be easily replaced or recharged that facilitates effective health monitoring. The proposed routing protocol has achieved better network stability, network lifetime, energy efficiency and throughput as compared to Stable Increased Throughput Multi-Hop Protocol for Link Efficiency in Wireless Body Area Networks (SIMPLE) and Reliable Energy Efficient Critical Data Routing in Wireless Body Area Networks (REEC) routing protocols. It has been validated through simulation results. KEYWORDS Intra wireless body sensor network (Intra-WBSN), Body node coordinator (BNC), Relay, Wireless body sensor network (WBSN), Energy efficiency.

Wireless Video Sensor Networks (WVSNs) - a type of WSNs - comprise of sensor nodes that can capture, process and communicate video frames. The battery powered sensor nodes have limited hardware resources while video processing and communication are resource intensive tasks i.e., require high-end processors, large memory and bandwidth. Video encoding is a popular method used to reduce the communication overhead
but being an inherently complex process it results in higher computational energy-drain on video sensor nodes. This establishes an interesting computation-communication tradeoff for energy efficient video communication (encoding and transmission) in WVSNs. In this paper, we study this computation-communication tradeoff under Intel-imote2 based single-hop and multi-hop video sensor networks testbed by empirically evaluating selected implementations of the MPEG-4 (Part 2) and H.264/AVC encoders. The analysis has been carried out to characterize the performance of encoders in terms of energy efficiency, compression efficiency and video distortion. The experimental results show that in single-hop WVSNs, MPEG-4 is energy efficient over H.264 whilst in multihop WVSNs, H.264 is energy efficient over MPEG-4.

Multi-hop communication systems gained popularity in wireless communications; they can be used to extend the coverage of the network and reduce the transmitted power. The transmission of data from the source node to the destination node in multi-hop communications undergoes through intermediate relay nodes. In this paper, we study the performance of multi-hop communication systems, in terms of average bit error rate (BER) with Binary frequency shift keying assuming the κ-µ fading channel model. Due to the difficulty in finding the probability density function (PDF) of the end-to-end signal to noise ratio (SNR) and hence for the performance metrics, we use Gaussian Mixture (GM) approximation technique to approximate the PDF of the end to end SNR assuming the κ-µ fading models as weighted sums of Gaussian distributions. Numerical results are provided for the BER of binary frequency shift keying (BFSK) of amplify and forward (AF) multi-hop communication systems assuming different values for the fading parameters (and for different number of hops. Numerical results are validated by comparing them with simulation results.

Most Software-Defined Networking (SDN) based centralized architectures for mobile multi-hop wireless networks propose using one or more of the following: infrastructure for hosting stationary SDNC, out-of-band single-hop (direct) communication links, location-tracking, or existing IP connectivity. Such architectures are inadequate for infrastructure-less networks having low-capacity links and susceptibility to high interference, packet losses, and collisions.

We describe a novel centralized opportunistic reactive routing protocol called CORR that allows a mobile SDN Controller (SDNC) to establish connectivity by identifying a subset of nodes in the network and making them the network backbone for forwarding packets. The SDNC learns the network topology via the backbone nodes, reducing the network load and improving the scalability. We evaluate CORR for a wide range of network sizes, densities, and traffic rates. Our ns3 simulation results indicate that CORR provides up to 10% better packet delivery ratio than AODV while incurring at least 1.5x lower network load and 3x lower delay, making it energy efficient and suitable for time-sensitive applications

Mobile Ad-hoc Network (MANET) is an emerging technology, infrastructure less with self-organizing, self healing, multi-hop wireless routing networks in real time. In such networks, many routing problems arise due to complexity in the network mobility which results from difficulty in achieving energy efficient routing in the field of MANET. Due to the dynamic nature and the limited battery energy of the mobile nodes, the communication links between intermediate relay nodes may fail frequently, thus affecting the routing performance of the network and also the availability of the nodes. Though existing protocols are not
concentrating about communication links and battery energy, node links are very important factor for improving quality of routing protocols because Node Rank helps us to determine whether the node is within
transmission range or out of transmission range through considering residual energy of the node during the routing process.

An ad hoc wireless network, or simply an ad hoc network, consists of a collection of geographically distributed nodes that communicate with one other over a wireless medium. An ad hoc network differs from cellular networks in that there is no wired infrastructure and the communication capabilities of the network are limited by the battery power of the network nodes. One of the original motivations for ad hoc networks is found in military applications. A classic example of ad hoc networking is network of war fighters and their mobile platforms in battlefields. Indeed, a wealth of early research in the area involved the development of packet-radio networks (PRNs) and survivable radio networks . While military applications still dominate the research needs in ad hoc networking, the recent rapid advent of mobile telephony and plethora of personal digital assistants has brought to the fore a number of potential commercial applications of ad hoc networks. Examples are disaster relief, conferencing, home networking, sensor networks, personal area networks, and embedded computing applications [37].

One of the most complicated issues is to measuring the delay performance of end to end nodes in Multi-hop Wireless Networks. The two nodes are communicating via hopping over the multiple wireless links. The fact that is each node has to concentrate not only its own generated traffic, but also relayed one. Observing unfairness particularly for transmissions among nodes that are more than one hop Most of the existing works deals with the joint congestion control and scheduling algorithm, which does not focusing the delay performance. In turn, considering the throughput metric alone although for congestion control flows, throughput is the repeated difficult performance metric Packet delay is also important because practical congestion control protocols need to establish the timeouts for the retransmissions based on the packet delay, such parameters could significantly impact the speed of recovery when loss of packets occurred. The related issues on the delay-performance First, for long flows, the end to end delay may grow in terms of square with based on the number of hops. Second, it is difficult to control the end-to-end delay of each flows. TDMA schedules the transmissions in a fair way, in terms of throughput per connection, considering the communication requirements of the active flows of the network. It does not work properly in the multi-hop scenario, because it is generated only for single hop networks, We propose The Leaky Bucket Algorithm, in addition to joint congestion control and scheduling algorithm in multi-hop wireless networks. The proposed algorithm not only achieves the provable throughput and also considering the upper bounds of the delay of each flow. It reduces the transmission time by delivering packets at a constant bit rate even it receives the packet at a busty way.

Vehicular Ad Hoc Network (VANET) is a class of unusual remote ad hoc network, which has superior node portability and it can respond to rapid topology changes. Designing of optimal cluster-based multi-hop clustering approach for VANET is a major challenge due to the active change of network and link capacity. Several earlier proposed models do not consider the dynamic topology, the mobility characteristics, the limited driving direction of VANET and they require more energy. Clustering is a system for gathering nodes, making the network increasingly dynamic. With the unconsciousness of nodes, at some point, its less energy creates execution issues in network and topology changes. The main intention of the paper is to study the recent literature on optimal route-finding in VANET, also to study literature on minimizing the delay of signals between the nodes, and also to design an energy-efficient VANET. The study is carried out for network parameters such as optimal route, energy efficiency, network lifetime, etc.