Andrea Lupia

Evaluation of the Energy Consumption Introduced by a Trust Management Scheme on Mobile Ad-hoc Networks

Nodes in mobile ad-hoc networks communicate each other using the wireless transmission. Many protocols have been proposed allowing the establishment of multi-hop paths to connect source and destination nodes. The absence of a physical link between the nodes and the multi-hop routing lead to a lack of security. Different typologies of attack effective against MANETs have been investigated thoroughly, and many solutions have been proposed to take the required countermeasures. Many of them are based on the cryptography, protecting data with digital signatures and hash chains, but they are not useful when a fair node is compromised later in time. Using a Trust Management Scheme can help in these situations, allowing to evaluate dynamically if a node is trustworthy or not. The computation of a trust value requires the monitoring of the interactions between nodes, therefore it has an effect on the energy consumption, which is an important issue of ad-hoc networks. Energy availability is limited for the nodes in a MANET, so the security measures that they adopt must not excessively increase the consumption.

Performance evaluation of secure AODV with trust management under an energy aware perspective

Ad-hoc networks allow nodes communication without an infrastructure, so they can be used in many environments. This lack of infrastructure introduces many security threats to the nodes in the network. Communication between nodes must be reliable, and protocols for MANETs need to make it possible. Due to the wireless channel and to the possible malicious behavior of nodes, it is necessary to introduce security mechanisms to avoid possible attacks in the network. The introduction of a trust management system on a well-known protocol such as SAODV protocol can protect against more attacks from malicious nodes, making wireless communication reliable and more secure. In this contribution Black hole and gray hole attacks will be detected, so communication will not be disrupted. Moreover, in order to understand as the energy consumption due to additional introduced security mechanisms, an energetic analysis is also performed on SAODV with and without trust management.

A new application for enhancing VANET services in emergency situations using the WAVE/802.11p standard

Car-to-car communication (C2C) makes possible offering many services for vehicular environment, mainly to improve the safety. The decentralized kind of these networks requires new protocols to distribute information. The V2X communication requires On-Board Units (OBUs) in the vehicles, and Road-Side Units (RSUs) on the roads. The proposed application uses the peculiarities of the VANETs to advise danger or emergency situations with V2V and V2I message exchange. IEEE 802.11p is the standard on which the communication is based, that provides the PHY and MAC layers. The performance of the application will be evaluated through many simulations executed in different scenarios, to provide general data independent from them.

Energy consumption evaluation of SAODV with trust management scheme under gray-hole attacks

Mobile ad-hoc networks allow communication between mobile nodes without the existence of an infrastructure, so they are adaptable also in hostile environments. Using the wireless communication leads to a lack of security. Due to the characteristics of mobile nodes, they have batteries as power source, so their energy is constrained. A routing protocol for MANETs has to take into account this constraint, limiting the amount of used energy. Introducing security measures to protect the network against malicious nodes has an impact on the energy amount required to nodes. To improve security of the network, there are already proposals that use cryptography to secure routing packets. In this contribution, a trust management system is introduced into the well-known protocol SAODV, to protect the network against effective attacks not protected by that protocol. The proposal is evaluated using gray hole attack and comparing performances and energy consumption between the SAODV with and without Trust Management Scheme.

A probabilistic energy-efficient approach for monitoring and detecting malicious/selfish nodes in mobile ad-hoc networks

MANETs are networks composed of mobile nodes connected using the wireless medium to communicate each other. The MANET nature makes it subject to various types of security leaks. External nodes could interfere with the communication, fair nodes could be compromised at any time by malicious agents. Another issue regards the limited amount of energy available to nodes, so their behavior could become selfish under some conditions. Many proposals detect these behaviors using a trust management system, but the activity of packet monitoring is energy-consuming. The main aim of this proposal is the reduction of the energy required by the monitoring system without lowering detection performance. Various simulations show that the achievement of this result is obtained through the application of a probabilistic approach, having also better performance in terms of time needed to detect misbehaviors.

A new call admission control scheme based on pattern prediction for mobile wireless cellular networks

Recently, cellular networking has become really popular, because of its different and growing fields of interest. It is able to satisfy user requirements in terms of Quality of Service, especially when mobility is present, managing hand-over issues in an adequate manner. So, it is very important to decide whether a new connection can be accepted into the system, in order to maximize bandwidth utilization while avoiding quality degradations, with more emphasis for non-tolerant applications. In this paper, the attention is not focused on a particular prediction scheme, but it is shown how a statistical approach can enhance system performance. We employ a general predictor (that can be based on Markov theory, neural networks, data mining approach or similars) and then we integrate it with a threshold-based statistical bandwidth multiplexing scheme in order to propose the Prediction-Based MUltipleXing Call Admission Control (PB-MUX CAC) scheme for cellular networks with mobile hosts. It is able to manage users mobility and to mitigate it, minimizing the amount of wasted bandwidth. Many simulation campaigns have been carried-out, giving us the possibility of evaluating the performance of the proposed idea in terms of number of admitted flows, bandwidth utilization and call blocking/dropping probability.

Trust management using probabilistic energy-aware monitoring for intrusion detection in mobile ad-hoc networks

The security is a key aspect in Mobile Ad-hoc Networks (MANETs), because the communication between the nodes is obtained using the wireless transmission, and the network setup is done without an infrastructure. In this scenario it is possible to perform internal and external attacks compromising the network functions. Moreover, the adoption of Intrusion Detection System (IDS) to discover internal attacks is often energy consuming highly reducing the network lifetime. At this purpose, our proposal is the design and adoption of an energy-aware probabilistic monitoring module useful to IDS, to better perform in a MANET scenario where not only security but also energy constraints need to be accounted. The proposed scheme has been analyzed by an energy point of view and considering also its efficacy to discover malicious nodes under different network conditions.

Vehicular networking and channel modeling: A new Markovian approach

Vehicular networking is rapidly growing in the last years, due to its ability of enhancing users everyday-life, in terms of comfort, security and QoS. New services are being implemented and the research activity on the topic is embracing different OSI layers, like the network and application ones. Many efforts have been also given at the PHY layer. In this paper we focus our attention on a new approach for modeling the wireless channel of VANETs communications. In the literature many channel models have been proposed, but most of them work at the bit level or they investigate only some aspects of channel interaction. In this work we provide a high level IEEE802.11p channel model based on Discrete Time Markov Chain (DTMC) modeling, useful in every simulation context. The proposed model is called Markovian Vehicular Channel Model (MVCM) and it is based on the concept of Packet Error Rate (PER) discretization: we do not consider the performance analysis at the bit level, but we derive the proposed model by computing the PER, associated to different observation times. The effectiveness of the proposed idea has been evaluated through a deep campaign of simulations.

An energy-efficient technique for MANETs distributed monitoring

Dishonesty detection in mobile and wireless networks is a task that typically relies on watchdog techniques. However, these medium overhearing-based techniques are prone to cause a high energy consumption. In an attempt to address this problem, several proposals adopted trust management as an alternative solution that is able to overcome the shortcomings of cryptography-based solutions when facing inside attacks. Unfortunately, these trust-based solutions remain mostly unable to reduce energy consumption. In this paper we propose a distributed time division-based monitoring strategy to achieve the required security levels while optimizing the energy consumption. Our proposal accounts for both trust and link duration among honest peers to fairly divide the monitoring period, and takes advantage of the periodically exchanged hello messages to make this solution fully distributed. Simulations results evidence the energy efficiency achieved by our proposal, especially for high density scenarios (>120 nodes) where the consumption becomes stable and does not increase with the number of nodes, while ensuring high detection ratios of malicious nodes (>85%).

TEEM: Trust-based Energy-Efficient Distributed Monitoring for Mobile Ad-hoc Networks

Detecting malicious and selfish nodes in mobile and wireless networks is a task that typically relies on watchdog techniques. However, such medium overhearing techniques are prone to cause a high energy consumption. In this paper we propose a distributed time division-based monitoring strategy to achieve the high security levels required while consuming less energy. Our proposal involves both trust and link duration among honest peers to fairly divide the monitoring period, and takes advantage of the periodically exchanged hello messages to make this solution fully distributed. Simulations results evidence our proposal energy efficiency, especially for high density scenarios (>100 nodes) where the consumption became stable and does not increase with the number of nodes (<4300 W·s), while ensuring high detection ratios of malicious nodes (>90%).