Optimizing cooperative cognitive radio networks with opportunistic access

Optimal resource allocation for cooperative cognitive radio networks with opportunistic access to the licensed spectrum is studied. Resource allocation is based on minimizing the symbol error rate at the receiver. Both the cases of all-participate relaying and selective relaying are considered. The objective function is derived and the constraints are detailed for both scenarios. It is then shown that the objective functions and the constraints are nonlinear and nonconvex functions of the parameters of interest, that is, source and relay powers, symbol time, and sensing time. Therefore, it is difficult to obtain closed-form solutions for the optimal resource allocation. The optimization problem is then solved using numerical techniques. Numerical results show that the all-participate system provides better performance than its selection counterpart, at the cost of greater resources

Automated Sensing System for Monitoring Road Surface Condition Using Fog Computing

The principle point of this task is to build up an Intelligent Monitoring System used to screen the Road Surface Condition using Fog Computing that increases the road safety. Multiple solutions have been proposed which make use of mobile sensing, more specifically contemporary applications and architectures that are used in both crowd sensing and vehicle based sensing. Nonetheless, these initiatives have not been without challenges that range from mobility support, location awareness, low latency as well as geo-distribution. As a result, a new term has been coined for this novel paradigm, called, fog computing

Enhanced Internet Access in MANETs: A Robust and Efficient Gateway Detection Approach with Amplified Backing

When a certain gateway is connected to a significant number of mobile devices, the quality of service begins to decline. As a result, we propose that the number of mobile devices up to which a specific gateway performs well within expectations be identified, and that this number be referred to as the gateway's capacity. The capacity of each node should then be verified in the optimum gateway discovery protocol before connecting to the gateway for the best results. Trust-based systems might help protect decentralised, self-organized networks like dedicated cellular carriers and dedicated vehicle networks against insider attacks. To guard against external threats, A/V encryption and access control might be utilised. Cryptographic systems, for example, are prevention-focused

An Effective Approach for Recovering From Simultaneous Node Failures in Wireless Sensor Networks

In wireless sensor - actor networks, sensors probe their surroundings and forward their data to actor nodes. Actors collaboratively respond to achieve predefined application mission. Since actors have to coordinate their operation, it is nec essary to maintain a stron gly connected network topology at all times. Failure of one or multiple actors may partition the inter - actor network into disjoint segments, and thus hinders the network operation. Autonomous detection and rapid recovery procedures ar e highly desirable in such a case . One of the effective recovery methodologies is to autonomously reposition a subset of the actor nodes to restore connectivity. Contemporary recovery schemes either impose high node relocation overhead or extend some of th e inter - actor data pat hs. This paper overcomes these shortcomings and presents extended version of DCR named RAM, to handle one possible case of a multi - actor failure with Least - Disruptive topology Repair (LeDiR) algorithm for minimal topological changes . Upon failure detection , the backup actor initiates a recovery process that relocates the least num ber of nodes

UAV-Assisted Wireless Powered Cooperative Mobile Edge Computing:Joint Offloading, CPU Control, and Trajectory Optimization

This article investigates the unmanned-aerial-vehicle (UAV)-enabled wireless powered cooperative mobile edge computing (MEC) system, where a UAV installed with an energy transmitter (ET) and an MEC server provides both energy and computing services to sensor devices (SDs). The active SDs desire to complete their computing tasks with the assistance of the UAV and their neighboring idle SDs that have no computing task. An optimization problem is formulated to minimize the total required energy of UAV by jointly optimizing the CPU frequencies, the offloading amount, the transmit power, and the UAV’s trajectory. To tackle the nonconvex problem, a successive convex approximation (SCA)-based algorithm is designed. Since it may be with relatively high computational complexity, as an alternative, a decomposition and iteration (DAI)-based algorithm is also proposed. The simulation results show that both proposed algorithms converge within several iterations, and the DAI-based algorithm achieve the similar minimal required energy and optimized trajectory with the SCA-based one. Moreover, for a relatively large amount of data, the SCA-based algorithm should be adopted to find an optimal solution, while for a relatively small amount of data, the DAI-based algorithm is a better choice to achieve smaller computing energy consumption. It also shows that the trajectory optimization plays a dominant factor in minimizing the total required energy of the system and optimizing acceleration has a great effect on the required energy of the UAV. Additionally, by jointly optimizing the UAV’s CPU frequencies and the amount of bits offloaded to UAV, the minimal required energy for computing can be greatly reduced compared to other schemes and by leveraging the computing resources of idle SDs, the UAV’s computing energy can also be greatly reduced

ARPNetSteg: Network Steganography using Address Resolution Protocol

Steganography is a technique that allows hidden transfer of data using some media such as Image, Audio, Video, Network Protocol or a Document, without its existence getting noticed. Over the past few years, a lot of research has been done in the field of Image, Video and Audio Steganography but very little work has been done in Network Steganography. A Network Steganography technique hides data in a Network Data Unit, i.e., a Network Protocol Packet. In this paper we present an algorithm ARPNetSteg that implements Network Steganography using the Address resolution protocol. Our technique is a robust technique that can transfer 44 bits of covert data per ARP reply packet

ARPNetSteg: Network Steganography using Address Resolution Protocol

Steganography is a technique that allows hidden transfer of data using some media such as Image, Audio, Video, Network Protocol or a Document, without its existence getting noticed. Over the past few years, a lot of research has been done in the field of Image, Video and Audio Steganography but very little work has been done in Network Steganography. A Network Steganography technique hides data in a Network Data Unit, i.e., a Network Protocol Packet. In this paper we present an algorithm ARPNetSteg that implements Network Steganography using the Address resolution protocol. Our technique is a robust technique that can transfer 44 bits of covert data per ARP reply packet