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Over the last decade, mobile Adhoc networks have expanded dramatically in popularity, and their impact on the communication sector on a variety of levels is enormous. Its uses have expanded in lockstep with its growth. Due to its instability in usage and the fact that numerous nodes communicate data concurrently, adequate channel and forwarder selection is essential. In this proposed design for a Cognitive Radio Cognitive Network (CRCN), we gain the confidence of each forwarding node by contacting one-hop and second level nodes, obtaining reports from them, and selecting the forwarder appropriately with the use of an optimization technique. At that point, we concentrate our efforts on their channel, selection, and lastly, the transmission of data packets via the designated forwarder. The simulation work is validated in this section using the MATLAB program. Additionally, steps show how the node acts as a confident forwarder and shares the channel in a compatible method to communicate, allowing for more packet bits to be transmitted by conveniently picking the channel between them. We calculate the confidence of the node at the start of the network by combining the reliability report for the first hop and the reliability report for the secondary hop. We then refer to the same node as the confident node in order to operate as a forwarder. As a result, we witness an increase in the leftover energy in the output. The percentage of data packets delivered has also increased. [ABSTRACT FROM AUTHOR]

Neighbor discovery is an important first step after the deployment of ad hoc wireless networks since they are a type of network that do not provide a communications infrastructure right after their deployment, the devices have radio transceivers which provide a limited transmission range, and there is a lack of knowledge of the potential neighbors. In this work two proposals to overcome the neighbor discovery in static one-hop environments in the presence of collisions, are presented. We performed simulations through Castalia 3.2, to compare the performance of the proposals against that for two protocols from the literature, i.e. PRR and Hello, and evaluate them according to six metrics. According to simulation results, the Leader-based proposal (O(N)) outperforms the other protocols in terms of neighbor discovery time, throughput, discoveries vs packets sent ratio, and packets received vs sent ratio, and the TDMA-based proposal is the slowest ( O (N 2) ) and presents the worst results regarding energy consumption, and discoveries vs packets sent ratio. However, both proposals follow a predetermined transmission schedule that allows them to discover all the neighbors with probability 1, and use a feedback mechanism. We also performed an analytical study for both proposals according to several metrics. Moreover, the Leader-based solution can only properly operate in one-hop environments, whereas the TDMA-based proposal is appropriate for its use in multi-hop environments. [ABSTRACT FROM AUTHOR]

Neighbor discovery represents a first step after the deployment of wireless ad hoc networks, since the nodes that form them are equipped with limited-range radio transceivers, and they typically do not know their neighbors. In this paper two randomized neighbor discovery approaches, called CDH and CDPRR, based on collision detection for static multi-hop wireless ad hoc networks, are presented. Castalia 3.2 simulator has been used to compare our proposed protocols against two protocols chosen from the literature and used as reference: the PRR, and the Hello protocol. For the experiments, we chose five metrics: the neighbor discovery time, the number of discovered neighbors, the energy consumption, the throughput and the number of discovered neighbors versus packets sent ratio. According to the results obtained through simulation, we can conclude that our randomized proposals outperform both Hello and PRR protocols in the presence of collisions regarding all five metrics, for both one-hop and multi-hop scenarios. As novelty compared to the reference protocols, both proposals allow nodes to discover all their neighbors with probability 1, they are based on collision detection and know when to terminate the neighbor discovery process. Furthermore, qualitative comparisons of the existing protocols and the proposals are available in this paper. Moreover, CDPRR presents better results in terms of time, energy consumption and number of discovered neighbors versus packets sent ratio. We found that both proposals achieve to operate under more realistic assumptions. Furthermore, CDH does not need to know the number of nodes in the network. [ABSTRACT FROM AUTHOR]

Neighbor discovery is a crucial first step after the deployment of wireless ad hoc networks, which do not have a communications infrastructure. In this paper we present analytical models of randomized neighbor discovery protocols for static one-hop environments: CDPRR (Collision Detection Probabilistic Round Robin) and CDH (Collision Detection Hello). For CDPRR we assumed a geometric distribution and a uniform distribution for CDH. For comparison purposes, we chose two protocols from the literature, i.e., Hello and PRR, to be used as reference. To assess the performance of the proposals we carried out a mathematical study regarding six metrics, i.e., neighbor discovery time, energy consumption, overhead (number of packets sent), packet delivery ratio, the CDF of discoveries, and percentage of idle slots, and presented graphical results obtained from the equations. According to the analytical results, CDH protocol outperforms the other solutions regarding the neighbor discovery time, energy consumption, number of packets sent, packet delivery ratio and CDF of discoveries, while CDPRR achieves good results and it is better than Hello and PRR in terms of neighbor discovery time, energy consumption, CDF of discoveries and the overhead (number of packets sent). Moreover, we found that CDPRR presents more percentage of idle slots than PRR, which is a clear advantage in terms of energy consumed and number of packets sent. In addition, as novelty compared to the reference protocols, we found that both CDH and CDPRR protocols manage to discover all the neighbors, know when to terminate the discovery process, and achieve to operate under more realistic assumptions. We also focused the study on the CDH protocol varying the slot width, and demonstrated that the number of nodes in the network can be unknown, still providing reasonable results. [ABSTRACT FROM AUTHOR]