62,729 research outputs found
On the effect of combining cooperative communication with sleep mode
Cooperation is crucial in (next-generation) wireless networks as it can greatly attribute to ensuring connectivity, reliability, performance, ... Relaying looks promising in a wide variety of network types (cellular, ad-hoc on-demand), each using a certain protocol. Energy efficiency constitutes another key aspect of such networks, as battery power is often limited, and is typically achieved by sleep mode operation. As the range of applications is very broad, rather than modelling one of the protocols in detail, we construct a high-level model capturing the two essential characteristics of cooperation and energy efficiency: relaying and sleep mode, and study their interaction. The used analytical approach allows for accurate performance evaluation and enables us to unveil less trivial trade-offs and to formulate rules-of-thumb applicable across all potential scenarios
Toward a Wired Ad Hoc Nanonetwork
Nanomachines promise to enable new medical applications, including drug
delivery and real time chemical reactions' detection inside the human body.
Such complex tasks need cooperation between nanomachines using a communication
network. Wireless Ad hoc networks, using molecular or electromagnetic-based
communication have been proposed in the literature to create flexible
nanonetworks between nanomachines. In this paper, we propose a Wired Ad hoc
NanoNETwork (WANNET) model design using actin-based nano-communication. In the
proposed model, actin filaments self-assembly and disassembly is used to create
flexible nanowires between nanomachines, and electrons are used as carriers of
information. We give a general overview of the application layer, Medium Access
Control (MAC) layer and a physical layer of the model. We also detail the
analytical model of the physical layer using actin nanowire equivalent
circuits, and we present an estimation of the circuit component's values.
Numerical results of the derived model are provided in terms of attenuation,
phase and delay as a function of the frequency and distances between
nanomachines. The maximum throughput of the actin-based nanowire is also
provided, and a comparison between the maximum throughput of the proposed
WANNET, vs other proposed approaches is presented. The obtained results prove
that the proposed wired ad hoc nanonetwork can give a very high achievable
throughput with a smaller delay compared to other proposed wireless molecular
communication networks.Comment: submitted to IEEE International Conference on Communications 2020
(ICC 2020
Bayesian signaling game based efficient security model for MANETs
Game Theory acts as a suitable tool offering promising solutions to security-related concerns in Mobile Ad Hoc Networks (i.e., MANETs). In MANETs, security forms a prominent concern as it includes nodes which are usually portable and require significant coordination between them. Further, the absence of physical organisation makes such networks susceptible to security breaches, hindering secure routing and execution among nodes. Game Theory approach has been manipulated in the current study to achieve an analytical view while addressing the security concerns in MANETs. This paper offers a Bayesian-Signaling game model capable of analysing the behaviour associated with regular as well as malicious nodes. In the proposed model, the utility of normal nodes has been increased while reducing the utility linked to malicious nodes. Moreover, the system employs a reputation system capable of stimulating best cooperation between the nodes. The regular nodes record incessantly to examine their corresponding nodes’ behaviours by using the belief system of Bayes-rules. On its comparison with existing schemes, it was revealed that the presented algorithm provides better identification of malicious nodes and attacks while delivering improved throughput and reduced false positive rate
A New Scheme for Minimizing Malicious Behavior of Mobile Nodes in Mobile Ad Hoc Networks
The performance of Mobile Ad hoc networks (MANET) depends on the cooperation
of all active nodes. However, supporting a MANET is a cost-intensive activity
for a mobile node. From a single mobile node perspective, the detection of
routes as well as forwarding packets consume local CPU time, memory,
network-bandwidth, and last but not least energy. We believe that this is one
of the main factors that strongly motivate a mobile node to deny packet
forwarding for others, while at the same time use their services to deliver its
own data. This behavior of an independent mobile node is commonly known as
misbehaving or selfishness. A vast amount of research has already been done for
minimizing malicious behavior of mobile nodes. However, most of them focused on
the methods/techniques/algorithms to remove such nodes from the MANET. We
believe that the frequent elimination of such miss-behaving nodes never allowed
a free and faster growth of MANET. This paper provides a critical analysis of
the recent research wok and its impact on the overall performance of a MANET.
In this paper, we clarify some of the misconceptions in the understating of
selfishness and miss-behavior of nodes. Moreover, we propose a mathematical
model that based on the time division technique to minimize the malicious
behavior of mobile nodes by avoiding unnecessary elimination of bad nodes. Our
proposed approach not only improves the resource sharing but also creates a
consistent trust and cooperation (CTC) environment among the mobile nodes. The
simulation results demonstrate the success of the proposed approach that
significantly minimizes the malicious nodes and consequently maximizes the
overall throughput of MANET than other well known schemes.Comment: 10 pages IEEE format, International Journal of Computer Science and
Information Security, IJCSIS July 2009, ISSN 1947 5500, Impact Factor 0.42
System Performance Analysis of Cooperative Communication in Wireless Ad Hoc Networks
Wireless ad hoc networks have been attracting more and more attentions in recent years from both academia and industry, because of their low deployment costs and broad applications. Due to the scarcity of the radio spectrum, supporting concurrent transmissions by exploiting the spatial frequency reuse gain is necessary to enhance spectrum utilization. On the other hand, cooperative communication is a practical technique for realizing the spatial diversity gain to mitigate the detrimental effect of wireless channel and enhance the transmission reliability. Enabling concurrent cooperative transmissions across a network can achieve both types of gains. Due to the broadcast nature of wireless communications, the concurrent cooperative transmissions using the same radio channel generate interference to each other, which is the main performance-limiting factor. Accurate characterization of interference is a fundamental step towards evaluating the performance of cooperative communication in a wireless ad hoc network. However, the distributed network operation, random node locations, interference redistribution due to relay transmissions, and dynamic traffic arrival pose significant challenges in interference characterization.
Under the protocol interference model, this thesis evaluates the effectiveness of cooperative communication in a wireless ad hoc network from a perspective of overall network performance through investigating the network throughput, which captures the tradeoff between single-link cooperation gain and network-wide reduced spatial frequency reuse due to relay transmissions. In particular, based on stochastic geometry, the outage probabilities of direct and cooperative transmissions are derived to characterize single-link cooperation gain. On the other hand, according to a randomized scheduling scheme, the expected numbers of concurrent direct and cooperative transmissions that can be accommodated within
the network coverage area are calculated to characterize network-wide reduced spatial frequency reuse. The analytical results show that a locally beneficial cooperation decision is not guaranteed to be network-wide beneficial.
The number of potential relays determines the achievable performance of a cooperative link, and varies for different source-destination pairs due to random relay locations. This thesis proposes an opportunistic cooperation strategy based on the number of potential relays available for each source-destination pair. Under the physical interference model, the correlation of node locations induces the correlation of interference power. Via modeling
node locations as a Poisson point process (PPP) and based on the Campbell's theorem, the temporal correlation coefficient of interference power at a destination node is analyzed. In addition, we derive the outage probability of opportunistic cooperation while taking into account the spatial and temporal interference correlation. The overall network performance can be enhanced by adjusting the proportion of concurrent cooperative transmissions.
In addition to random node locations and interference redistribution, dynamic traffic arrival further complicates the interference characterization. This thesis investigates the performance of cooperative communication in a wireless ad hoc network with unsaturated traffic, which introduces a correlation between the interferer density and packet retransmission probability. Based on queueing theory and stochastic geometry, the interference power is characterized from two aspects, namely stationary interferer density and interference correlation in two consecutive time-slots, to evaluate the network performance. The analytical results show that the performance analysis under the assumption of independent
interference power overestimates the network performance.
The proposed theoretical performance analysis framework provides a step towards better understanding of the benefits and limitations of cooperative communication in wireless ad hoc networks with spatially random nodes, and in turn provides useful insights on protocol design and parameter setting for large-scale networks.4 month
Analysis of a Reputation System for Mobile Ad-Hoc Networks with Liars
The application of decentralized reputation systems is a promising approach
to ensure cooperation and fairness, as well as to address random failures and
malicious attacks in Mobile Ad-Hoc Networks. However, they are potentially
vulnerable to liars. With our work, we provide a first step to analyzing
robustness of a reputation system based on a deviation test. Using a mean-field
approach to our stochastic process model, we show that liars have no impact
unless their number exceeds a certain threshold (phase transition). We give
precise formulae for the critical values and thus provide guidelines for an
optimal choice of parameters.Comment: 17 pages, 6 figure
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