Top PDF Realtime multiprocessor for mobile ad hoc networks

Realtime multiprocessor for mobile ad hoc networks

Realtime multiprocessor for mobile ad hoc networks

RAPTOR2000 rapid prototyping system, the test environ- ment can be reused as described in section 2.4.1. The hier- archical design of the ASIC shortens development time, be- cause parts as the processing elements and the switch boxes have to be designed only once an then can be multiply instan- tiated. This is also an advantage of our SoCs as wire-length can be calculated better in advance and more aggressive sig- naling strategies can be used. In the fabricated multiproces- sor (see Fig. 6) four processing enginges are connected to one switch box. Two of these processor clusters form the eight-core MPSoC. This architecture results from a design space exploration and simulation of different architectures as described in Sect. 1 and achieves a high ressource effi- ciency which is important for low power applications as mo- bile ad hoc networks. The proposed system has been manu- factured in 180 nm UMC standard-cell-technology and oc- cupies an area of 25 mm 2 using six metal layers. It em- beds 2.1 MBit memory and consists of 1.6 million transistors. At a clock frequency of 100 MHz, the average power con- sumption is 772 mW. At this speed, a communication band- width of up to 2.1 Gbps is achieved for each link of the NoC. 4.2 Gbps throughput per switch box are achieved in total with all six links active which is a disadvantage of memory shared switching. The off-chip communication bandwidth via two physical ports is 500 MBit/s. A daughterboard for RAPTOR2000 has been developed, comprising the MPSoC, 4 MB external memory, and a Spartan XC3S1500 FPGA, in- tegrating an interface to the RAPTOR2000 motherboard (see Fig. 7). The user can easily interact with the MPSoC, using the PCI bus interface of RAPTOR2000.
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An Overview on Intrusion Detection in Manet

An Overview on Intrusion Detection in Manet

A mobile ad hoc network (MANET) is a self-configuring of mobile devices network connected without wires and hence MANET has become a very popular technology now days. A MANETS are the networks that are building, when some mobile nodes come in the mobility range of each other for data transfer and communication. In MANET, nodes are not stable hence the communication topology is not stable due to this vulnerable for attacks. MANET devices are connected via wireless links without using an existing network infrastructure or centralized administration due to which MANETs are not able to diverse types of attacks and intrusions. Hence intrusion detection has attracted many researchers. This paper gives an overview and different methods to detect intrusion in MANET.
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Design and Implementation of AMRP for Multi hop wireless Mobile ad hoc Networks

Design and Implementation of AMRP for Multi hop wireless Mobile ad hoc Networks

A large number of studies on multi-hop wireless networks have been devoted to system stability while maximizing metrics like throughput or utility. These metrics measure the performance of a system over a long time-scale. For a large class of applications such as video or voice over IP, embedded network control and for system design; metrics like delay are of prime importance [1]. The delay performance of wireless networks, however, has largely been an open problem. This problem is notoriously difficult even in the context of wire line networks, primarily because of the complex interactions in the network (e.g., superposition, routing, departure, etc.) that make its analysis amenable only in very special cases like the product form networks. The problem is further exacerbated by the mutual interference inherent in wireless networks which, complicates both the scheduling mechanisms [3] and their analysis. Some novel analytical techniques to compute useful lower bound and delay estimates for wireless networks with single hop traffic were developed
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Reliable and Efficient Broadcasting in Asymmetric Mobile Ad Hoc Networks Using Minimized Forward Node List Algorithm

Reliable and Efficient Broadcasting in Asymmetric Mobile Ad Hoc Networks Using Minimized Forward Node List Algorithm

Wireless ad hoc networks, also called Mobile Ad Hoc Networks (MANETs) are collections of autonomous mobile nodes or terminals that communicate with each other by forming a multi-hop wireless radio network. Each node in a MANET can act as both a host and a router to receive and forward packets and it can randomly move around, leave the network or switch off. Network wide broadcasting is a fundamental operation in ad hoc networks. In broadcasting, a source node sends a message to all the other nodes in the network. The advantage is that one packet can be received by all neighbors; the disadvantage is that it interferes with the sending and receiving of other transmissions, creating exposed terminal problem, that is, an outgoing transmission collides with an incoming transmission and hidden terminal problem that is, two incoming transmissions collide with each other. In general, broadcasting refers to a process of transmitting a packet so that each node in a network receives a copy
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COMPARATIVE ANALYSIS OF DIFFERENT ENCRYPTION TECHNIQUES IN MOBILE AD HOC NETWORKS (MANETS)

COMPARATIVE ANALYSIS OF DIFFERENT ENCRYPTION TECHNIQUES IN MOBILE AD HOC NETWORKS (MANETS)

Security is provided through security services such as confidentiality. The goal of confidentiality is to control or restrict access to sensitive information to the only authorized individuals. MANET uses an open medium, so usually all nodes within the transmission range can obtain the data. One way to keep information confidential is to use data encryption schemes. Moreover, compromised nodes may be a threat to confidentiality if the cryptographic keys are not encrypted and stored in the node [2]. Another challenge when it comes to MANET security is the key management issue. In order to prevent the malicious nodes from joining in the networks, it's necessary to authenticate the nodes when they are joining in. Due to the restricted energy and computational capability of MANETs, it's necessary to design a light weight and storage efficient key management scheme [3] [4].
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Intrusion detection in mobile ad hoc network

Intrusion detection in mobile ad hoc network

Intrusion detection in MANETs, however, is challenging for a number of reasons [9-11]. These networks change their topologies dynamically due to node mobility; lack of concentration points where traffic can be analyzed for intrusions; utilize self configuring multi-party infrastructure protocols that are susceptible to malicious manipulation; and rely on wireless communication channels that provide limited bandwidth and are subject to noise and intermittent connectivity. To overcome these constraints, a number of decentralized intrusion detection approaches tailored specifically for MANETs have been proposed. These approaches, however, have focused almost exclusively on detecting malicious behavior with respect to MANET routing protocols and have provided little evidence that they are applicable to a broader range of threats, including attacks on conventional protocols, which also pose new problems in MANETs. This paper describes a generalized, cooperative intrusion detection architecture proposed as the foundation for all intrusion detection and supporting activities in mobile ad hoc wireless networks.
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An Efficient Quality of Service Based Routing Protocol for Mobile Ad Hoc Networks

An Efficient Quality of Service Based Routing Protocol for Mobile Ad Hoc Networks

The routing overload of AODV and QAODV almost zero at minimum speed. This is because once a route discovery process is completed; there is no need to perform the discovery process again. As shown in fig:7 the routing overload increases in AODV and QAODV with the increase of maximum moving speed. In higher mobility networks, a node which is on the route for transmitting traffic flow has higher possibility to move out of the transmission range of the upstream or the downstream nodes. The upstream nodes are nodes that transmit the packets to the considered moving node and the down stream nodes are those that receive packets from the considered moving node.
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Identification of Closest and Phantom Nodes in Mobile Ad Hoc  Networks

Identification of Closest and Phantom Nodes in Mobile Ad Hoc Networks

There are several services that build on the availability of closest node location information like geographic routing in spontaneous networks, data gathering in sensor networks, movement coordination among autonomous robotic nodes, location specific services for hand held devices and danger warning or traffic monitoring in vehicular networks. Ad hoc networking protocols and location-aware services require that mobile nodes identify the location of their closest nodes. Such a process can be easily misuses or stop by opposed nodes. In absence of a priori trusted nodes, the spotting and identifying of closest node position presents challenges that have been scarcely investigated in the literature. Node can also send message from one to many nodes in a broadcasting manner here.
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DYNAMIC K-MEANS ALGORITHM FOR OPTIMIZED ROUTING IN MOBILE AD HOC NETWORKS

DYNAMIC K-MEANS ALGORITHM FOR OPTIMIZED ROUTING IN MOBILE AD HOC NETWORKS

The papers offering a complete clustering-based method for route optimization in MANETs are greatly abundant. The authors are aware of futurist research of [10, 11], where Mobility Based Metric for Clustering has been used to effectively find the optimized paths in MANETs with group mobility behavior, in which an colony of mobile nodes travels with similar speed and direction, as in highway traffic. In this method, by calculating the variance of a mobile node’s speed regarding each of its neighbors, the totality positional speed of mobile nodes is estimated. A low variance quantity demonstrates that this mobile node is relatively less mobile to its neighbors. Consequently, cluster heads are chosen from mobile nodes with low variance quantity in their neighborhoods.
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Mobile ad hoc networks tcp performance and comparison over routing protocols

Mobile ad hoc networks tcp performance and comparison over routing protocols

An adhoc network is a collection of nodes that do not need to rely on a predefined infrastructure to stablish and maintain pending on there capacity with respect to cpu, memory and battery. With the proliferation of mobile computing devices, the demand for continuous network connectivity regardless of physical location has spurred interest in the use of mobile ad hoc networks. A mobile ad hoc network is a network in which a group of mobile computing devices communicate among themselves using wireless radios, without the aid of a fixed networking infrastructure. Their use is being proposed as an extension to the Internet, but they can be used anywhere that a fixed infrastructure does not exist, or is not desirable. the congestion control mechanism of TCP reacts adversely to packet losses due to temporarily broken routes in wireless networks. So, i propose a simple heuristic, called fixed RTO, to distinguish betien route loss and network congestion and thereby improve the performance of the routing algorithms. The TCP protocol has been extensively tuned to give good performance at the transport layer in the traditional wired network environment. Hoiver, TCP in its present form is not ill-suited for mobile ad hoc networks (MANETs) where packet loss due to broken routes can result in the counterproductive invocation of TCP’s congestion control mechanisms.
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A Cross-Layer Delay-Aware Node Disjoint Multipath Routing Algorithm for Mobile Ad Hoc Networks

A Cross-Layer Delay-Aware Node Disjoint Multipath Routing Algorithm for Mobile Ad Hoc Networks

To meet these QoS requirements, recent study on multihop networks has demonstrated that cross- layer design which can significantly improve the system performance [5]-[6]. To guarantee QoS in MANETs for delay sensitive applications two factors are considered. Firstly, route selection criterion must be QoS-aware i.e., it must consider the link quality before using the link to transmit. Secondly, the instantaneous response to the dynamics of MANET topology changes must be considered so that the route changes are seamless to the end user over the life time of a session. Generally, a QoS model defines the methodology and architecture by which certain types of services can be provided in the network. Protocols such as routing, resource reservation signaling and MAC must cooperate to achieve the goals set by the QoS model. QoS routing is one of the most essential parts of the QoS architecture [7]–[9]. Multipath approach has many advantages such as load balancing, QoS assurance and fault tolerance [10]- [12]. Several multipath routing protocols have been proposed so far in the literature. One of the earliest multipath routing protocols is Ad hoc On demand Multipath Distance Vector (AOMDV) [13]. AOMDV is a variant of Ad Hoc On Demand Distance Vector (AODV) [14] which establishes loop-free and link-disjoint paths based on the minimum hop count. QoS AODV (QS-AODV) in [15] extended the basic AODV routing protocol to provide QoS support in MANETs. It uses hop count as criterion for choosing the route with an assumption that NODE_TRAVERSAL_TIME (NTT) is constant. Stephane Lohier et al.[16] proposed reactive QoS routing protocol that also deals with delay and bandwidth requirements. In his proposal, QoS routes are traced by node to node and NTT is an estimate of the average one-hop traversal time, which includes queue, transmission, propagation, and other delays.
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Energy-Aware Performance Metric for AODV and DSDV Routing Protocols in Mobile Ad-Hoc Networks

Energy-Aware Performance Metric for AODV and DSDV Routing Protocols in Mobile Ad-Hoc Networks

DSDV is a proactive routing protocol based on the classical distributed Bellman-Ford routing algorithm [2]. In DSDV[4] messages are shared between the mobile nodes (i.e., nodes are in the same transmission range).The nodes will continuously evaluate the routes to all reachable nodes and attempt to maintain consistent up-to date information. The routing table updates will sent periodically throughout the network thus the table will maintain its consistency but this will generate a lot of traffic in the network. Each node will maintain a routing table in which all of the possible destinations within the network and the number of hops to each destination are recorded [3]. Each entry in the routing table is marked with a sequence number that is assigned by the destination node; the sequence numbering system will avoid the formation of loops.
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Towards a network management solution for vehicular delay-tolerant networks

Towards a network management solution for vehicular delay-tolerant networks

In order to overcome the above-presented issues, several architectures have been proposed, including Vehicular Ad-hoc Networks (VANETs) [2], Delay-Tolerant Networks (DTNs) applied to vehicular communications [3], and even Vehicular Delay-Tolerant Networks (VDTNs) [4]. In VANETs, vehicles are used as mobile nodes in order to enable communications. These communications can be classified into vehicle to vehicle (V2V) or vehicle to infrastructure (V2I). Both approaches assume an available end-to-end link among communication end points. However, they are not able to deal with network partition, disconnection, or long time delays. A possible solution to these limitations is the store-carry-and-forward paradigm proposed by the DTN architecture. In DTNs, vehicles are used to transport data between disconnected parts of the network. Data is stored until a contact opportunity is available. When this contact opportunity is available, data is forwarded based on a specific routing protocol, in order to reach its final destination.
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Secure Clustering in Vehicular Ad Hoc Networks

Secure Clustering in Vehicular Ad Hoc Networks

With The growth of wireless communication technology, two elementary wireless network models have been established for the wireless communication system [1] [2]. The fixed infrastructure wireless model consists of a large number of Mobile Nodes and relatively fewer, but more powerful, fixed nodes. The communication between a fixed node and a MN within its range occurs via the wireless medium. However, this requires a fixed infrastructure. Another system model, an Ad-hoc Network, it is a self- organizing collection of Mobile Nodes that form an infrastructure less wireless network on a shared wireless channel. Nodes which lie in the range of each other can easily communicate, while those which are far apart from each other communicate over the routers. Their deploying cost is relatively low as compared to other wireless networks because there is no necessity of a proper fixed infrastructure. Security is an important issue which is faced while deploying the ad hoc networks; the security issues under consideration are availability, confidentiality, integrity, authentication and non- repudiation [3] [4]. Availability refers that the system must survive in critical conditions such as denial of service and worm attacks. The attackers also try to create hindrance in the
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Content delivery in vehicular ad hoc networks

Content delivery in vehicular ad hoc networks

solution that considers a mobile social scenario in which nodes forward their content to their neighbors using opportunistic communications. The forwarding is performed con- sidering user profile and preferences instead of relying on the proximity of the mobile nodes. Although proposed for MANETs, the idea of social preferences may be applied to VANETs to improve content distribution solutions. RTAD [Sanguesa et al., 2015] is a real-time adaptive dissemination system in which vehicles decide the broadcast scheme to use, among a set of schemes, based on the current network density and topology information on the road. Thus, this solution is expected to perform well under different network conditions. Push-and-Track [Whitbeck et al., 2012] is a framework that takes advantage of opportunistic ad-hoc communications to offload the network core infras- tructure when disseminating content to various nodes. This solution was proposed for scenarios in which many nodes may be interested in the same content. Some nodes are selected to initially receive the content, which they then periodically disseminate to their neighbors. One strength of this solution is that the disseminators keep track of the nodes that have already received the content by adopting an acknowledgment scheme, which is very useful for increasing the dissemination coverage area.
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Manet Load Balancing Parallel Routing Protocol

Manet Load Balancing Parallel Routing Protocol

This paper has proposed a load balancing parallel routing protocol (LBPRP) for mobile ad-hoc networks. LBPRP allows routing multiple packets in parallel from a source node to a destination node over disjoint paths. The LBPRP balances the data load through calculating each path speed and selecting the path with the high speed for sending first. LBPRP is a load balancing parallel routing protocol achieving low communication delays, high packet delivery ratios, high routing path stability, and low routing overheads.

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Proposed protocol for secured multi path routing in ad hoc networks

Proposed protocol for secured multi path routing in ad hoc networks

The common mobile network usually appears in forms, such as the cellular network or the wireless local area networks. Among cellular network, communication of portable terminal must finish with the aid of base station and switching of portable exchanger; in the wireless local area network, the portable terminal is connected to an existing infrastructural network through the wireless access point. However, today’s cellular networks use fix infrastructures, which are vulnerable to some special environments or the emergency such as the search and rescue after nature calamity. As a consequence, in such conditions, we need to rely on a kind of mobile communication network technology as the Ad Hoc network which individual nodes cooperate by forwarding packets for each other to allow nodes to communicate beyond direct wireless transmission range. Furthermore, it requires no centralized administration or fixed network infrastructure such as base stations or access points, and can be quickly and inexpensively set up as needed in the Ad Hoc network. They can be used in many special applications such as military usage, sensor networks, urgent and sudden occasion, and remote open-air area, interim occasions, personal communication, and business application. Until now, many routing protocols of Ad Hoc network are proposed [1], [2], [3], [4], [5], [6]. Compared with other traditional communication networks, there are several characteristics such as without a pre-existing infrastructure, dynamic topologies, dispose automatically, transmission bandwidth- constrained, and energy constrained operation in Ad Hoc network. Unfortunately, most of authors design originally routing protocols which mainly rely on the efficiency of the routing protocol and the quality of transmission of data. They do not consider the secure problem in the Ad Hoc network. Therefore, many experts and scholars have proposed different solutions to solve the secure problem in the Ad Hoc network
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A Combined Solution for Routing and Medium Access Control Layer Attacks in Mobile Ad Hoc Networks

A Combined Solution for Routing and Medium Access Control Layer Attacks in Mobile Ad Hoc Networks

Abstract: Problem statement: In Mobile Ad hoc Network (MANET), both the routing layer and the Medium Access Control (MAC) layer are vulnerable to several attacks. There are very few techniques to detect and isolate the attacks of both these layers simultaneously. In this study, we developed a combined solution for routing and MAC layer attacks. Approach: Our approach, makes use of three techniques simultaneously which consists of a cumulative frequency based detection technique for detecting MAC layers attacks, data forwarding behavior based detection technique for detecting packet drops and message authentication code based technique for packet modification. Results: Our combined solution presents a reputation value for detecting the malicious nodes and isolates them from further network participation till its revocation. Our approach periodically checks all nodes, including the isolated nodes, at regular time period λ. A node which recovers from its misbehaving condition is revoked to its normal condition after the time period λ. Conclusion/Recommendations: By simulation results, we show that our combined solution provides more security by increased packet delivery ratio and reduced packet drops. We also shown that our approach has less overhead compared to the existing technique.
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A MODEL FOR CONGESTION CONTROL OF TRANSMISSION CONTROL PROTOCOL IN MOBILE WIRELESS AD HOC NETWORKS

A MODEL FOR CONGESTION CONTROL OF TRANSMISSION CONTROL PROTOCOL IN MOBILE WIRELESS AD HOC NETWORKS

Other researchers look from different perspectives since nodes in ad hoc networks use wireless channel as a shared medium to send and receive data. The shared channel allows a single sender to transmit at a time. Therefore, senders within a local neighborhood have to compete for wireless channel access before transmitting. In addition, the number of segments that can be in-flight concurrently is limited from a source to a destination. Fu et al. (2005) observed that packet drop due to link-layer contention dominates in ad hoc networks while buffer overflow-induced packet loss is rare.
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A Comprehensive Study on Defence Against Wormhole Attack Methods in Mobile Ad hoc Networks

A Comprehensive Study on Defence Against Wormhole Attack Methods in Mobile Ad hoc Networks

Due to inherent specifications of MANETs, they face many security issues compared to present ordinary networks (Hoang et al, 2006). An attacker can contravention them by passively or actively attacking on MANETs (Rutvij et al, 2010). A passive attack is difficult to detect as the adversary obtains information without disturbing normal network operations; traffic analysis, traffic monitoring and eavesdropping are examples of passive attacks. On the other hand, active attack can be internal or external in which adversary alters information and thus, disturbs network operations; examples of such attack are impersonation, modification, fabrication, jamming, message replay, denial-of service. TABLE I. shows the characteristics and examples of active and passive attacks. Both active and passive attacks can be launched on any layer of the network protocol stack. Table II. The paper (Perkins et al, 2004) shows some examples of attacks on different layers.
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