Ad-Hoc Network

A mobile ad hoc network is a dynamically self-organizing network without any central administrator or infrastructure support. If two nodes are not within the transmission range of each other, other nodes are needed to serve as intermediate routers for the communication between the two nodes [1]. Moreover, mobile devices wander autonomously and communicate via dynamically changing network. Thus, frequent change of network topology is a tough challenge for many important issues, such as routing protocol robustness, and performance degradation resiliency [11][12]. Proactive routing protocols require nodes to exchange routing information periodically and compute routes continuously between any nodes in the network, regardless of using the routes or not. This means a lot of network resources such as energy and bandwidth may be wasted, which is not desirable in MANETs where the resources are constrained [1-3]. On the other hand, on-demand routing protocols don't exchange routing information periodically. Instead, they discover a route only when it is needed for the communication between two nodes [1, 6, 7]. Due to dynamic change of net-work on ad hoc networks, links between nodes are not permanent. In occasions, a node cannot send packets to the intended next hop node and as a result packets may be lost. Loss of packets may affect on route performance in different ways. Among these packet losses, loss of route reply brings much more problems, because source node needs to re-initiate route discovery procedure. In this study we propose a power aware routing protocol which has a new aspect to find out path between source to destination according to available power of node.

The Request-to-Send and Clear-to-Send (RTS/CTS) mechanism was introduced to minimize the collisions due to "Hidden Nodes" in wireless networks. It tried well to solve this problem over Carrier Sense Multiple Access (CSMA), but it gave rise to some more problems. These problems are "Exposed Node Problem", "False Blocking Problem" and "Masked Node Problem". Exposed node is a node which is in transmission range of sender but it is not the actual receiver. False blocking arises when any RTS is sent to a blocked node. Masked node problem is the case in which RTS/CTS to solve Hidden Node problem. These problems decreased the performance of RTS/CTS badly. Till now several modifications in RTS/CTS mechanism have been proposed but none of them solved all these problems completely and hence RTS/CTS mechanism remained as an option in IEEE802.11 Distributed Coordination Function. So in this survey paper we are going to discuss briefly the drawbacks of RTS/CTS mechanism and some effective modifications in RTS/CTS mechanism which have been proposed to overcome the drawbacks of this mechanism.

In the recent years, the Ad-Hoc networks have been the focus of many researches especially in the routing protocols which include Proactive and Reactive routing. The strategy of forwarding the data packets from the source to the destination is the ultimate goal of routing protocols. Hence, the difference between these protocols is based on searching, maintenance and recovering the route path. The potential problem in Ad-Hoc networks is how to determine the optimum routing protocol that satisfies the needs of the application regarding to some criteria. This work will present the evaluation of proactive routing protocol Routing Information Protocol (RIP) and reactive routing protocol Dynamic Source Routing (DSR) based on the QualNet simulation. Moreover, the performance of these routing protocols will be measured based on the throughput, delay, average jitter and energy consumption metrics. The present paper shows that the routing information protocols (RIP) have better evaluation performance compared to DSR in the scenario.

Human advancement moving towards more associated in nature. it has been confirmed it even 10 years before when the electrical message was invented. From that point forward, there was no stop for the human to associate everything through electrical/electronic and computerized channels. As of late, the business has named it IoT which characterizes as the Internet of Things. The name characterizes its temperament as its Inter associating the "things". You can substitute any usable item that can be interconnected as a "thing" i.e., mechanical articles like vehicles, electrical articles like fans, TV, and so forth This opens up heaps of occasion to taunt any "things" on the web permit outsiders to assume control over the control.in every second a huge amount of data has been transmitted and saved from many resources in a secured manner. Data security, otherwise called network protection, means" measures taken to ensure a PC or PC framework (as on the Internet) against unapproved access or attack." Password securing our workstations and work telephones are instances of information security. Individuals and organizations do this for a bigger scope to shield touchy individual and business data from being spilled. This paper will assist with examining the dangers associated with data security and review the techniques associated with the data security and attack detection mechanism.

On wireless computer networks, ad-hoc mode is a method for wireless devices to directly communicate with each other. Operating in ad-hoc mode allows all wireless devices within range of each other to discover and communicated in peer-to-peer fashion. One main challenge in design of these networks is their vulnerability to security attacks. The growing popularity and widespread applications of wireless networks are directly proportionate to their propensity for security exploitation. In this paper we have discussed about the potential attacks and security issues of routing protocols face by ad-hoc network.

Natural and catastrophic disasters can cause damage to the communication system, the damage may be complete or it may be partial. In such areas communication and exchange of information plays a very important role and become difficult to happen in such situations. So, the rescue systems should be installed in those areas for the rescue operations and to take important decisions about how to make a connection from there to the outside world. Wireless communication network architecture should be setup in disaster areas for the communication to happen and to gather information. In this document, wireless ad-hoc access node network architecture has been proposed. These access nodes acts as hotspot for certain area in which they are set up such that the Wi-Fi capable devices get connected to them for communication to happen. If the mobile battery is drained in such situations wireless charging using microwave is shown in this paper. Performance analysis of the communication transport layer protocols is shown and new-SCTP algorithm is developed which shows the better results in terms of cumulative packet loss.

Security is a main concern now a day. A spontaneous network is a special kind of ad-hoc network; Ad-hoc wireless network is an infrastructure less network that is there is no central coordination for network operations. As and when a new node comes in the region of the network it will spontaneously form the network. Security is a major concern while designing and developing spontaneous ad-hoc network in mobile devices. Spontaneous ad hoc networks require well defined, energy efficient and user-friendly security mechanisms. This method presents data transmission using a secure protocol for spontaneous wireless ad-hoc network which uses an hybrid symmetric or asymmetric scheme and the trust between the users in order to exchange initial data and to exchange the secret keys that is used to encrypt the data. In spontaneous wireless ad hoc network creation there is no need of any infrastructure no need of any administrator for handling the services. No need of any external base for handling functionalities of network. This protocol is a completely self-configured secure protocol that is able to create a network and share services without any central infrastructure. Network creation stages, protocol messages, and network management are explained. This protocol allows sharing of resources among users in a secure environment. In human communication model any two people that are physically close to each other can communicate with each other without any central server, anybody those who want to communicate can come join, communicate and leave the network without central server. In spontaneous network there is no server or any central infrastructure between nodes to communicate, anybody want to communicate can come join and leave the network without central infrastructure. A user can create its own resources or it can request from its neighbour user, because it allows resource sharing.

Wireless Ad hoc network is a set of wireless devices
which move randomly and communicate with other node via
radio signal. Ad-hoc networks may be logically represented as a
set of clusters by grouping together nodes on the basis of
different criteria such as 1-hop and k-hop  that are in close
boundary with one another. Clusters are formed by diffusing
node identities along the wireless links. Different heuristics
employ different policies to elect cluster heads. Several of these
policies are biased in favour of some nodes. As  a result, these
nodes should greater responsibility and may deplete their energy
faster, causing them to drop out of the network. Therefore, there
is a need for load-balancing among cluster-heads to allow all
nodes the opportunity to serve as a cluster-head. In this paper,
different cluster head election mechanism are discussed in the
one hop clustering approach.

Mobile ad hoc network is a standalone network capable of autonomous operation where nodes
communicate with each other without the need of any existing infrastructure. They are self configuring,
autonomous, quickly deployable and operate without infrastructure. Mobile ad hoc networks consist of
nodes that cooperate to provide connectivity and are free to move and organize randomly. Every node is
router or an end host, in general autonomous and should be capable of routing traffic as destination
nodes sometimes might be out of range. Nodes are mobile since topology is very dynamic and they have
limited energy and computing resources. These nodes are often vulnerable to failure thus making mobile
ad hoc networks open to threats and attacks. Communication in MANET relies on mutual trust between
the participating nodes but the features of MANET make this hard. Nodes sometimes fail to transmit and
start dropping packets during the transmission. Such nodes are responsible for untrustworthy routing. A
trust based scheme can be used to track these untrustworthy nodes and isolate them from routing, thus
provide trustworthiness. In this paper a trusted AODV (ST-AODV) protocol is presented which assigns a
trust value for each node. Nodes are allowed to participate in routing based on their trust values. A
threshold value is assigned and if the nodes trust value is greater than this value its marked as
trustworthy node and allowed to participate in routing else the node is marked untrustworthy. The STAODV
increases PDR and decreases delay thereby enhancing the QoS metrics and trustworthiness in
AODV based MANET routing. The work is implemented and simulated on NS-2. The simulation result
shows the proposed ST-AODV provides more trustworthy routing compared with general AODV in
presence of packet dropping nodes in MANET.

Wireless is playing the wide role in today’s industrial application. Central idea of this paper is to enhance quality of service (QoS) for multimedia transmission over ad-hoc network. This paper describes the operational of different QoS routing protocols, their properties and various parameters advantages and disadvantages. Also describes the use of QoS in Cross layer routing protocol. Finally, it concludes by study of all these cross layer QoS routing protocols.

In MANETs (Mobile Ad Hoc Networks) communication at the mobile nodes can be achieved by using multihop wireless links. The architecture of such network is based not on a centralized base station but on each node which acts as a router and forwards data packets to other nodes in the network. The aim of each protocol, in an ad-hoc network, is to find valid routes between two communicating nodes. These protocols must be able to handle high mobility of the nodes which often cause changes in the network topology. This paper evaluates four ad-hoc network protocols (AODV, DSDV, DSR and TORA) in different network scales taking into consideration the mobility factor. The evaluation of these four protocols was carried out using Network Simulator-2 (ns2), and the poor performance of TORA may be attributed to its implementation in this package. Therefore further investigation of TORA implementation in ns2 needs to be carried out.

As an emerging platform wireless Adhoc sensor network emerged in the field of remote sensing data assessment, analysis. Today network plays main role in one’s life mainly communication take place through this network so network security is one of the main concern. The security work in this area is mainly focusing over denial of communication at the routing or medium access control level. Network survivability is one of the main concerns. It reduces the battery power of the network hence one cannot send message through that network for the desired time it will be expensive to use new battery. In this paper we are trying to reduce this kind of attack in wireless sensor network by using cluster mechanism. Here we are using MOCA(Multiple over lapping cluster Algorithm)it create new cluster in each desired or valid route.

On wireless computer networks, ad-hoc mode is a method for wireless devices to directly communicate with each other. Operating in ad-hoc mode allows all wireless devices within range of each other to discover and communicated in peer-to-peer fashion. One main challenge in design of these networks is their vulnerability to security attacks. The growing popularity and widespread applications of wireless networks are directly proportionate to their propensity for security exploitation. In this paper we have discussed about the potential attacks and security issues of routing protocols face by ad-hoc network.

The problems of the Mobile Ad-hoc Network are due to the limited resources of inactive mobile nodes and its low ability to cooperate due to network congestion. Furthermore, there is no central coordination that makes it difficult to predict the availability of mobile nodes. Hence, in this paper, we are implementing a free congestion zone (ConZone) where it can accept congested packet and re-route to the right path. These two mechanisms are thought to reduce the end-to-end delay ratio and the loss of the packets. At the same time, there is a possibility to improve the distribution ratio and packet throughput.

An Ad-Hoc network is a wireless, decentralized, dynamic network in which devices associate with each other in their link range, in which the basic 802.11 MAC protocol uses the Distributed Coordination Function (DCF) to share the media between various devices. But use of 802.11 MAC protocol in Ad-Hoc networks affected by different issues such as restricted power capacity, packet loss because of transmission error, various control traffic and failure to avoid packet collision. To solve these problems various protocols have been proposed. But we don't have any perfect protocol which can resolve the issues related to power management, packet collision and packet loss efficiently. In this research paper, we suggest a new protocol to adjust the upper & lower bounds for the contention window to decrease the number of collisions. As well as it proposes a power control scheme, triggered by the MAC layer to reduce the packet loss, energy wastage and decrease the number of collisions during transmission. The proposed MAC protocol is implemented and performance is compared with existing 802.11 MAC protocol. We computed the Packet Delivery Fraction(PDF), average End-to-End(e-e) delay, average throughput and packet loss in several conditions. We find proposed protocol is comparatively improved than the existing protocol.

This paper outlines experience with the implementation and deployment of wireless network with direct connection between the devices using Ad-hoc network. The work was prompted by the lack of published results concerning the issues associated with the implementation of ad-hoc network on actual wireless networks, as opposed to results of simulation experiments. I examined implementations of adhoc network is defined as the wireless network with direct connection between the devices. The connection is here been established dynamically while defining a session. While performing the communication, the communicating device discovers the other communicating device in the range so that effective communication will be drawn over the system. The search mechanism is performed till the target node is not identified.