PMSS: Producer Mobility Support Scheme Optimization with RWP Mobility Model in Named Data Networking

Abstract: The movement pattern of mobile producer plays an important role in mobility performance analysis of the wireless and mobile network. However, the producer mobility behavior is directly affecting the handoff latency and signaling overhead cost. Many researchers provide analytical investigation to analyze and solve the handoff problems and compared with the simulation result. To justify between simulation and analytical investigation, movement behavior of mobile node needs to be included in the analytical investigation to make it possible to compare with the simulation-based result. This paper incorporated Random WayPoint Mobility (RWPM) model, to determine the behavior of mobile producer, for analytical solution of producer mobility support in NDN. In this paper, we introduce mobility Interest packets to conveyed new prefix or location of mobile producer, a broadcasting strategy to facilitate the handoff process and the immobile anchor router was modified to perform a dual function that is, tagging of anchors and broadcasting of tagged mobility Interest packets. The performance analysis for mobile producer behavior and handoff latency shows that our proposed Producer Mobility Support Scheme (PMSS) reduces handoff latency compared to DNS-like and Home Agent routing approach

Information-Centric Semantic Web of Things

In the Semantic Web of Things (SWoT) paradigm, a plethora of micro-devices permeates an environment. Storage and information processing are decentralized: each component conveys and even processes a (very) small amount of annotated metadata. In this perspective, the node-centric Internet networking model is inadequate. This paper presents a framework for resource discovery in semantic-enhanced pervasive environments leveraging an information-centric networking approach. Information gathered through different Internet of Things (IoT) technologies can be exploited by both ubiquitous and Web-based semantic-aware applications through a uniform set of operations. Experimental results and a case study support sustainability and effectiveness of the proposal

Thwarting Sybil Attackers in Reputation-based Scheme in Mobile Ad hoc Networks

Routing in mobile ad hoc networks is performed in a distributed fashion where each node acts as host and router, such that it forwards incoming packets for others without relying on a dedicated router. Nodes are mostly resource constraint and the users are usually inclined to conserve their resources and exhibit selfish behaviour by not contributing in the routing process. The trust and reputation models have been proposed to motivate selfish nodes for cooperation in the packet forwarding process. Nodes having bad trust or reputation are detected and secluded from the network, eventually. However, due to the lack of proper identity management and use of non-persistent identities in ad hoc networks, malicious nodes can pose various threats to these methods. For example, a malicious node can discard the bad reputed identity and enter into the system with another identity afresh, called whitewashing. Similarly, a malicious node may create more than one identity, called Sybil attack, for self-promotion, defame other nodes, and broadcast fake recommendations in the network. These identity-based attacks disrupt the overall detection of the reputation systems. In this paper, we propose a reputation-based scheme that detects selfish nodes and deters identity attacks. We address the issue in such a way that, for normal selfish nodes, it will become no longer advantageous to carry out a whitewash. Sybil attackers are also discouraged (i.e., on a single battery, they may create fewer identities). We design and analyse our rationale via game theory and evaluate our proposed reputation system using NS-2 simulator. The results obtained from the simulation demonstrate that our proposed technique considerably diminishes the throughput and utility of selfish nodes with a single identity and selfish nodes with multiple identities when compared to the benchmark scheme

An Analysis of the Node Spatial Distribution of the Random Waypoint Mobility Model for Ad Hoc Networks

by nodes moving according to the random waypoint model, which is widely used in the simulation of mobile ad hoc networks. We extend an existing analysis for the case in which nodes are continuously moving (i.e., the pause time is 0) to the more general case in which nodes have arbitrary pause times between movements. We also generalize the mobility model, allowing the nodes to remain stationary for the entire simulation time with a given probability. Our analysis shows that the structure of the resulting asymptotic spatial density is composed by three distinct components: the initial, the pause and the mobility component. The relative values of these components depend on the mobility parameters. We derive an explicit formula of the one-dimensional node spatial density, and an approximated formula for the two-dimensional case. The quality of this approximation is veri ed through experimentation, which shows that the accuracy heavily depends on the choice of the mobility parameters. 1

A reputation-based mechanism to mitigate host misbehaviors in DTNs

Delay Tolerant Networking (DTN) is a network paradigm designed for disconnected networks. Message delivery in DTNs relies on the mobility of carriers, hosts that carry messages from a network partition to another. Context-Aware Adaptive Routing (CAR) is a routing protocol for DTNs with the aim to select the carrier with the highest chance of successful message delivery. CAR relies on the assumption that all hosts in the network are collaborative, i.e. that cooperate in the message forwarding process. In real-life environments hosts can not cooperate in such process and endanger communication among partitions. We propose RCAR, a decentralized approach based on reputation aimed to detect and exclude misbehaving hosts from the network. Simulation tests made on a human mobility model show that RCAR increases the message delivery probability of CAR in presence of misbehaving carriers. Delay Tolerant Networking (DTN) è un paradigma di comunicazione progettato per reti caratterizzate da elevati ritardi e frequenti disconnessioni. La comunicazione fra dispositivi posizionati in partizioni di rete differenti avviene sfruttando la mobilità dei cosiddetti carriers, dispositivi che trasportano fisicamente un messaggio da una partizione di rete all'altra per conto di un altro dispositivo. Context-Aware Adaptive Routing (CAR) è un protocollo di routing per DTN che seleziona il carrier avente la più elevata probabilità di corretta consegna di un messaggio. Il corretto funzionamento di CAR fa affidamento sulla collaborazione di tutti i carriers nel processo di consegna di un messaggio. In sistemi reali però i carriers possono non partecipare a tale processo, mettendo quindi a rischio la comunicazione. Questo documento presenta RCAR, un meccanismo di sicurezza basato sul concetto di reputazione volto ad individuare ed escludere i carriers non collaborativi dal processo di consegna dei messaggi. I risultati di simulazioni effettuate utilizzando un modello di mobilità realistico dei dispositivi mostrano come RCAR aumenti la percentuale di messaggi consegnati correttamente rispetto a CAR in presenza di carriers non collaborativi

A layered security approach for cooperation enforcement in MANETs

In fully self-organized MANETs, nodes are naturally reluctant to spend their precious resources forwarding other nodes' packets and are therefore liable to exhibit selfish or sometimes malicious behaviour. This selfishness could potentially lead to network partitioning and network performance degradation. Cooperation enforcement schemes, such as reputation and trust based schemes have been proposed to counteract the issue of selfishness. The sole purpose of these schemes is to ensure selfish nodes bear the consequences of their bad actions. However, malicious nodes can exploit mobility and free identities available to breach the security of these systems and escape punishment or detection. Firstly, in the case of mobility, a malicious node can gain benefit even after having been detected by a reputation-based system, by interacting directly with its source or destination nodes. Secondly, since the lack of infrastructure in MANETs does not suit centralized identity management or centralized Trusted Third Parties, nodes can create zero-cost identities without any restrictions. As a result, a selfish node can easily escape the consequences of whatever misbehaviour it has performed by simply changing identity to clear all its bad history, known as whitewashing. Hence, this makes it difficult to hold malicious nodes accountable for their actions. Finally, a malicious node can concurrently create and control more than one virtual identity to launch an attack, called a Sybil attack. In the context of reputation-based schemes, a Sybil attacker can disrupt the detection accuracy by defaming other good nodes, self-promoting itself or exchanging bogus positive recommendations about one of its quarantined identities. This thesis explores two aspects of direct interactions (DIs), i. e. Dis as a selfish nodes' strategy and Dis produced by inappropriate simulation parameters. In the latter case DIs cause confusion in the results evaluation of reputation-based schemes. We propose a method that uses the service contribution and consumption information to discourage selfish nodes that try to increase their benefit through DIs. We also propose methods that categorize nodes' benefits in order to mitigate the confusion caused in the results evaluation. A novel layered security approach is proposed using proactive and reactive paradigms to counteract whitewashing and Sybil attacks. The proactive paradigm is aimed at removing the advantages that whitewashing can provide by enforcing a non-monetary entry fee per new identity, in the form of cooperation in the network. The results show that this method deters these attackers by reducing their benefits in the network. In the reactive case, we propose a lightweight approach to detect new identities of whitewashers and Sybil attackers on the MAC layer using the 802.11 protocol without using any extra hardware. The experiments show that a signal strength based threshold exists which can help us detect Sybil and whitewashers' identities. Through the help of extensive simulations and real-world testbed experimentations, we are able to demonstrate that our proposed solution detects Sybil or whitewashers' new identities with good accuracy and reduces the benefits of malicious activity even in the presence of mobility

Distributed resource discovery: architectures and applications in mobile networks

As the amount of digital information and services increases, it becomes increasingly important to be able to locate the desired content. The purpose of a resource discovery system is to allow available resources (information or services) to be located using a user-defined search criterion. This work studies distributed resource discovery systems that guarantee all existing resources to be found and allow a wide range of complex queries. Our goal is to allocate the load uniformly between the participating nodes, or alternatively to concentrate the load in the nodes with the highest available capacity. The first part of the work examines the performance of various existing unstructured architectures and proposes new architectures that provide features especially valuable in mobile networks. To reduce the network traffic, we use indexing, which is particularly useful in scenarios, where searches are frequent compared to resource modifications. The ratio between the search and update frequencies determines the optimal level of indexing. Based on this observation, we develop an architecture that adjusts itself to changing network conditions and search behavior while maintaining optimal indexing. We also propose an architecture based on large-scale indexing that we later apply to resource sharing within a user group. Furthermore, we propose an architecture that relieves the topology constraints of the Parallel Index Clustering architecture. The performance of the architectures is evaluated using simulation. In the second part of the work we apply the architectures to two types of mobile networks: cellular networks and ad hoc networks. In the cellular network, we first consider scenarios where multiple commercial operators provide a resource sharing service, and then a scenario where the users share resources without operator support. We evaluate the feasibility of the mobile peer-to-peer concept using user opinion surveys and technical performance studies. Based on user input we develop access control and group management algorithms for peer-to-peer networks. The technical evaluation is performed using prototype implementations. In particular, we examine whether the Session Initiation Protocol can be used for signaling in peer-to-peer networks. Finally, we study resource discovery in an ad hoc network. We observe that in an ad hoc network consisting of consumer devices, the capacity and mobility among nodes vary widely. We utilize this property in order to allocate the load to the high-capacity nodes, which serve lower-capacity nodes. We propose two methods for constructing a virtual backbone connecting the nodes