Mobile Wireless Network Essay

MANET-“ A mobile ad-hoc network is a self-configuring infrastructure less network of mobile devices connected by wireless.”. Each device in a MANET is free to move independently in any direction, and will therefore change its links to other devices frequently. Each must forward traffic unrelated to its own use, and therefore be a router. The primary challenge in building a MANET is equipping each device to continuously maintain the information required to properly route traffic.

Geographic Adaptive Fidelity (GAF): Geographic Adaptive Fidelity is an energy-aware location based routing algorithm planned for mobile ad-hoc networks but has been used to WSNs. Geographic Adaptive Fidelity conserving energy by switching off redundant sensors nodes. In this routing protocol, the entire network is classified into number of static zones and a virtual grid is made for the covered region. Every node utilizes its GPS-indicated location to link itself with a point in the virtual grid. Nodes linked to the same point on the grid are assumed equivalent with respect to packet routing costs. Nodes within a zone cooperate by choosing one node to show the zone for a period of time whereas the rest of the nodes sleep. A sample situation is considered from

A group of wireless sensor nodes (devices) dynamically constructs a temporary network without the exercise of any pre-existing network infrastructure or centralized administration. The main goal of ad-hoc networking is multihop broadcasting in which packets are transferred from source node to destination node through the intermediate nodes (hops). The main function of multi hop WSN is to enable communication between two terminal devices through a bit of middle nodes, which are transferring information from one level to another level. On the foundation of network connectivity, it dynamically gets to determine that which nodes should get included in routing, each node involved in routing transmit the data to further

With the increasing dependency on wireless networks, the need for proper reliability analysis for Mobile ad hoc networks (Manets) is also increasing. Failure of Manets in areas like warfare, nuclear reactors, medical equipment and airplanes can lead to catastrophe. Unlike traditional networks, measuring the reliability of Manets is a tedious task as it involves dynamically changing topology. The existing methods for calculating reliability use two terminal analysis as the basis for calculation. It uses the same method used for traditional computer networks to calculate reliability. However, the method is not very efficient when it comes to the wireless networks as they are far different from traditional networks. It is also a time consuming task to identify all the nodes and links in a wireless network as nodes move freely in the network. In This paper, We are going to discuss about NLN(Node-Link-Node) technique which reduces the complexity of analyzing the reliability in Manets.

In disconnected MANET, p2p file sharing systems is based on two methods flooding based and advertisement based. First

This layer is used to coordinate node access to the shared wireless medium. The MAC is the core of communication protocol stack which provides the basic for achieving Quality of Service (QoS) in any wireless networks. A versatile MAC should support diverse applications and different types of data such as continuous, periodic, burst and non-periodic data along with high level QoS. MAC plays a major determining factor in improving overall network performance. The fundamental task in MAC protocol is to avoid collisions and to prevent simultaneous transmissions while preserving maximum throughput, minimum latency, communication reliability and maximum energy efficiency. It is important to note that while

There are number of metrics which are helpful for deciding the efficiency of a protocol. In this work the parameters used to evaluate the efficiency of a protocol are the packet delivery ratio, packet statistics in the network and the throughput of the network. The protocols AODV and AODVBC are checked against these parameters for their performance. Packet delivery ratio of the network is improved as the mobility with respect to the number of nodes changes. Increase in the PDR (Packet delivery ratio is because of the less number of packet drops when AODVBC is used. Fig. 4 justifies the better performance of AODVBC routing protocol over AODV protocol in terms of less number of packets drop.

With the drop of the hardware cost, more and more mobile devices with higher capacities are now used. The widely deployed wireless LAN and broadband wireless networks provide the ubiquitous network access for multimedia applications. Provision of Quality of Service (QoS) is challenging in mobile ad hoc networks because of the dynamic characteristics of mobile networks and the limited resources of the mobile devices. The wireless network is not reliable due to node mobility, multi-access channel and multi-hop communication.

Another attack the heavily attacks the performance of MANET is replay attack. The valid signed messages are captures and retransmitted by the replay attacker. The transmitter and the receiver nodes use timestamp for validating the signed messages. The freshness of routes is affected by this attack.

After a discussion of the challenges in planning a secure protocol and therefore the attacks, successive section discusses many secure routing protocols for ad hoc networks. [20]

VANETs are a exacting outward appearance of wireless network made by vehicles communicating among themselves and with roadside units (RSUs). The wireless communications afford by VANETs have great impending to make easy new services that could save thousands of lives and improve the driving knowledge. A key requirement for such services is that they are accessible with quality of service (QoS) assurance in terms of service reliability and availability. Safety is comprehend as principal attribute of Vehicular AdHoc Network (VANET) system.

Many networks are infrastructure less networks where the nodes can configure dynamically to form a useful network. There are many challenges in wireless networks as explored in [1]. The challenges are as follows.

Abstract— this paper is an involvement in the field of security study on mobile ad-hoc networks. Boundaries of the mobile ad hoc nodes have been considered in order to design a secure Ad hoc routing protocol that thwarts selfish and flooding attacks. We took the base of Ad hoc On Demand Routing Protocol (AODV); the most popular Routing protocol. The significance of the proposed protocol that should make sure security as wanted by providing a broad architecture of Trusted and PES Mechanism based smart Path Routing protocol (TBAODV) based on effective key management, secure neighbor detection, secure routing data’s, finding malicious nodes, and eliminating these nodes from routing table. Our results clearly show that our secured Ad hoc routing protocol increases the throughput and packet delivery ratio while it has a tolerable increase in the routing overhead and average delay. Also, security study proves in details that the proposed protocol is robust enough to thwart all classes of

One of the most promising and discussed technologies in the past decade is the wireless communication technology which allows each users to utilize devices that enable the access to information at any place any time. These demands make wireless communication networks the best solution for inter connect the devices and people worldwide. Unlike wired communication networks, which are comprised of devices that can communicate through wires, wireless networks are comprised of devices that communicate through media such as infra-red and radio signals. Wireless networks are generally classified into two categories: infrastructure-based and infrastructure less network (ad hoc wireless networks).

Mobile Adhoc Network(MANET) is a collection of two or more devices or terminals or hosts with the wireless communication with each other and the exchange of information from the existing networks.A MANET can be a standalone network or it can be a standalone network or it can be connected to the external networks.MANET consists of mobile platforms which are free to move. In this paper, we will focus on the current applications ,challenges and some of the protocols which provide the connectivity in mobile adhoc networks.The mode of operation of adhoc networks are basically peer to peer multihop mobile wireless networks where the information packets are transmitted via the intermediate nodes.The challenges include routing ,service ,billing