Suitable Relay Node Research Articles

Social mobility and geo-context aware macroscopic routing scheme for mobile opportunistic network

Mobile opportunistic networks (MONs) are deliberated as important aspect to proliferate the wireless communications. These networks pose several challenges such as network lifetime, storage capacity, and forwarding capacity. End-to-End routing schemes are considered as promising technique solution to deal with these issues. In this domain, opportunistic routing has gained huge attention because it follows the broadcasting nature of wireless communication and focus on selection of relay node for packet transmission to ensure the better quality of service (QoS) and energy efficiency. This work focuses on optimizing the next hop selection process and introduced reinforcement learning approach which considers distance, energy and link connectivity to assign the reward for different actions to identify the suitable relay node. Moreover, geo-context and social behaviour based opportunistic routing models are used to increase the reliability of next hop selection. Similarly, social model considers social profiling, social connectivity, and social interaction model to identify the relay node. The outcome of proposed approach is compared with several existing approaches such as prophet, spray and wait, and epidemic routing in terms of packet delivery, and network overhead. The relative study shows that the proposed approach achieves the average packet delivery as 47.22% and minimizes the network overhead.

A Bidirectional Relay-Assisted Underlay Device-to-Device Communication in Cellular Networks: An IoT Application for FinTech

The device-to-device (D2D) networks bear a close resemblance to future Internet-of-Things (IoT) networks. IoT plays a significant role in the FinTech industry, especially in data security and context-aware applications. D2D communication in cellular networks has emerged as a competent technology for the upcoming future cellular networks. To improve spectral efficiency and data secrecy, we propose a two-phase network coding-based two-way decode-and-forward (DF) relaying policy for D2D communication. First, a suitable relay node is selected considering the end-to-end signal-to-interference-plus-noise ratio (SINR). Then, an XOR-based DF operation is performed when the signal transmitted by both the D2D users (DUEs) is successfully decoded at the relay node. In order to analyze the performance of the proposed two-way communication system, we derive the outage probability expression as a function of various system parameters, such as the SINR, position of both the relays and DUEs, power splitting factor, number of relays, and data rate. Furthermore, we also derive an expression for the error probability and average throughput of the D2D link to evaluate a fair comparison of the proposed approach with the traditional methods. The analytical results are also validated with the simulation results to justify the efficacy of the proposed method.

Improved Multi-Path Routing for QoS on MANET

A Mobile Ad hoc NETwork (MANET) is a self-configuring network that is not reliant on infrastructure. This paper introduces a new multipath routing method based on the Multi-Hop Routing (MHR) technique. MHR is the consecutive selection of suitable relay nodes to send information across nodes that are not within direct range of each other. Failing to ensure good MHR leads to several negative consequences, ultimately causing unsuccessful data transmission in a MANET. This research work consists of three portions. The first to attempt to propose an efficient MHR protocol is the design of Priority Based Dynamic Routing (PBDR) to adapt to the dynamic MANET environment by reducing Node Link Failures (NLF) in the network. This is achieved by dynamically considering a node’s mobility parameters like relative velocity and link duration, which enable the next-hop selection. This method works more efficiently than the traditional protocols. Then the second stage is the Improved Multi-Path Dynamic Routing (IMPDR). The enhancement is mainly focused on further improving the Quality of Service (QoS) in MANETs by introducing a QoS timer at every node to help in the QoS routing of MANETs. Since QoS is the most vital metric that assesses a protocol, its dynamic estimation has improved network performance considerably. This method uses distance, linkability, trust, and QoS as the four parameters for the next-hop selection. IMPDR is compared against traditional routing protocols. The Network Simulator-2 (NS2) is used to conduct a simulation analysis of the protocols under consideration. The proposed tests are assessed for the Packet Delivery Ratio (PDR), Packet Loss Rate (PLR), End-to-End Delay (EED), and Network Throughput (NT).

From Single-Protocol to Large-Scale Multi-Protocol Quantum Networks

In the initial stage of the quantum Internet, most of the practical quantum networks have been deployed relying on diverse individual quantum key distribution (QKD) protocols. However, this single-protocol paradigm cannot fulfill the heterogeneous requirements of the users, hence market-penetration of quantum networks is limited. Given the recent advances in QKD protocols, the next generation quantum networks are expected to support both legacy and emerging QKD protocols. However, the evolution from single-protocol to multi-protocol quantum networks poses numerous challenging problems. As a remedy, we conceive a practical protocol translation framework for supporting this migration from single-protocol to large-scale multi-protocol quantum networks. Furthermore, we propose a programmable multi-functional relay node architecture for harmonizing the components of a suitable relay node. A pair of protocol translation policies are presented for meeting the challenging security requirements of migration requests, which are compared to the single-protocol-based migration solutions both in terms of the translation success probability attained (i.e., the proportion of migration requests with successful protocol translation), and the average relaying risk probability encountered (i.e., the mean of the relaying risk probabilities of end-to-end key negotiation in a quantum network). Finally, we highlight a suite of open problems in both quantum secure direct communication and quantum teleportation for research into future multi-protocol quantum networks.

Routing in Opportunistic Networks: Implementation and Research Challenges

Opportunistic Networks can be defined as Delay Tolerant Network, which are formed dynamically with participating nodes’ help. Opportunistic Networks follows Store-Carry-Forward principle to deliver/route the data in the network. Routing in Opportunistic Network starts with the Seed Node (Source Node) which delivers the data with the help of Intermediate nodes. Intermediate nodes store the data while roaming in the network until it comes in contact with appropriate forwarding node (relay node) or destination node itself. An extensive literature survey is performed to analyse various routing protocols defined for Opportunistic Network. With mobility induced routing, establishing and maintaining the routing path is a major challenge. Further, Store-Carry-Forward routing paradigm imposes various challenges while implementing and executing the network. Due to the unavailability of the suitable relay node, data needs to be stored within the Node’s Memory, imposes buffer storage issues at the node level. Also, uncontrolled flooding may impose link-level Congestion and treated as overhead to maintain the network. Another major challenge can be maintaining the energy level of the nodes in the network. Recently developed ONE (Opportunistic Network Environment) Simulator is used to simulate and emulate the environment required by Opportunistic Network. Along with the extensive literature survey of the protocols, few of the existing protocols viz. Direct Delivery, ProPHET, Epidemic and Spray & Wait Routing are implemented using ONE Simulator to analyse their performance while in execution. Results are being compared, and the researchers’ future direction is identified to address the open problems and challenges in Opportunistic Network.

A Universal Routing Algorithm Based on Intuitionistic Fuzzy Multi-Attribute Decision-Making in Opportunistic Social Networks

With the vigorous development of big data and the 5G era, in the process of communication, the number of information that needs to be forwarded is increasing. The traditional end-to-end communication mode has long been unable to meet the communication needs of modern people. Therefore, it is particularly important to improve the success rate of information forwarding under limited network resources. One method to improve the success rate of information forwarding in opportunistic social networks is to select appropriate relay nodes so as to reduce the number of hops and save network resources. However, the existing routing algorithms only consider how to select a more suitable relay node, but do not exclude untrusted nodes before choosing a suitable relay node. To select a more suitable relay node under the premise of saving network resources, a routing algorithm based on intuitionistic fuzzy decision-making model is proposed. By analyzing the real social scene, the algorithm innovatively proposes two universal measurement indexes of node attributes and quantifies the support degree and opposition degree of node social attributes to help node forward by constructing intuitionistic fuzzy decision-making matrix. The relay nodes are determined more accurately by using the multi-attribute decision-making method. Simulation results show that, in the best case, the forwarding success rate of IFMD algorithm is 0.93, and the average end-to-end delay, network load, and energy consumption are the lowest compared with Epidemic algorithm, Spray and Wait algorithm, NSFRE algorithm, and FCNS algorithm.

A fuzzy-based check-and-spray geocast routing protocol for opportunistic networks

Unlike communication networks which are traditionally assumed to be connected, Opportunistic networks (OppNets) are a type of wireless ad hoc networks with no guarantee of end-to-end path for data routing, which is due to node mobility, volatile links, and frequent disconnections. As such, data transmission among the nodes relies on their cooperation and this is realized in a store-and-carry fashion. To this end, several opportunistic routing techniques have been proposed in the literature, some of which using geocasting, a technique that consists of scheduling the message to a specific region toward its destination. This paper proposes a Fuzzy-based Check-and-Spray Geocast (FCSG) routing protocol for OppNets, in which a Check-and-Spray mechanism is used to control the message flooding within the destination cast and a fuzzy controller is used for selecting the suitable relay nodes to carry the message toward the destination, with the aim to improve the delivery ratio. Using simulations, the proposed FCSG protocol is shown to outperform the F-GSAF, GeoEpidemic and EECSG routing protocols in terms of overhead ratio, average latency, and delivery ratio, under varying number of nodes, buffer size, and Time-to-Live.

Handoff in WLAN/cellular systems based on a hybrid of WLAN bandwidth and ad hoc relaying strategies

The seamless vertical handoff from a wireless local area network (WLAN) to a cellular system yet poses a big challenge. While serving by a WLAN, a mobile node (MN) may enter a region with a low data rate before completing a handoff towards a cellular network. To maintain quality of service, a large amount of WLAN bandwidth must be allocated to compensate for the weakness of MN link. However, this mechanism does not work properly in dense hotspots because of the lack of WLAN bandwidth. An alternative is to employ relay nodes (RN) to remain connected to the AP. This scheme also does not operate well in a low-density hotspot because the chance of finding a suitable RN is low. In this paper, a hybrid solution that uses both WLAN bandwidth and potential RNs is proposed. It uses the trade-off between the WLAN bandwidth and the potential RNs to reach an optimum handoff performance in terms of call dropping probability. Initially, the probability of call dropping in relay mode is theoretically evaluated and compared with the simulation results. Next, the proposed Hybrid approach is modelled by assuming 5% and 10% of nods as the relay nodes. The results show the proposed method can significantly reduce call dropping probability in both low and high-density hotspots when compared with a relay or bandwidth-based approach. It also reduces new call blocking probability of the bandwidth only but slightly worse than the relay only methods.

Cooperative‐routing mechanism based on node classification and task allocation for opportunistic social networks

With the development of big data, the authors have witnessed the great success of the mobile internet that the number of intelligent mobile devices (MDs) has increased dramatically and the data that needs to be transmitted grows exponentially. The traditional end-to-end communication mechanism in social networks is difficult to satisfy enormous communication demands. Therefore, opportunistic social networks proposed that message applications should choose relay nodes to perform effective data transmission processes. Currently, some routing algorithms that utilise contextual information associated with nodes need to handle heavy computing tasks and manage large numbers of messages, which usually results in higher network overhead and network latency. Furthermore, the computing power of MDs is usually limited, message carriers may not be able to quickly find the suitable relay node because of their insufficient computing power, resulting in higher network latency and network overhead. In this study, they construct a cooperative-routing mechanism based on node classification and task allocation for opportunistic social networks. In their proposed strategy, the reliable relay nodes can be obtained by classifying nodes according to the social attributes of the nodes. The task of node classification will be uniformly assigned to other idle nodes according to their computing power.

A Novel Synchronous MAC Protocol for Wireless Sensor Networks with Performance Analysis.

Synchronous medium access control (MAC) protocols are highly essential for wireless sensor networks (WSN) to support transmissions with energy saving, quality services, and throughput in industrial, commercial and healthcare applications. In this paper, a synchronous channel access mechanism is designed, where sensors can reserve the contention free data transmission slots in different available channels. To reduce the delay of data transmission among the nodes in the mesh topology, a linear programming problem (LPP) model is designed to select suitable relay nodes. Moreover, the performance of the proposed MAC is analyzed and our models are validated with simulation and analytical results. The results show that our proposed MAC protocol outperforms the IEEE 802.15.4e MAC mechanism in terms of throughput, reliability, delay, energy, packet drop rate and transmission success rate.

Secure big data communication for energy efficient intra-cluster in WSNs

Big data communications in wireless sensor networks (WSNs) play a very important role in the energy efficiency and lifetime of routing schemes. Nowadays, multi-hop path routing schemes in WSNs have been widespread focused by scholars at home and abroad. However, most of the scholars focus only on the data communication between the cluster head (CH) node and the base station (BS), resulting in why the impacts of intra-cluster communications has not been paid enough attention. In this paper, we propose a new energy efficient intra-cluster data communication scheme (EEICS), for WSNs, to solve the energy and secure problem of the intra-cluster data communication. The presented scheme includes three key parts: a new layer scheme in one cluster that enables self-organization of local nodes and the width of each layer is not equal, a new multi-hop path selection algorithm for choosing a suitable relay node to forward data packets to the CH nodes and a secure communication mechanism to preserve the privacy of source nodes in the cluster. The residual energy of nodes is taken into consideration in our scheme in particular when it comes to the selection of the relay node. Our analysis and simulation can prove the advantage of our scheme in view of lifetime and the amount of data packages. The simulation part plays a significant role in analysing the security and performance of our scheme. At the end of simulation part, we present the qualitative analysis among EEICS and the conventional schemes such as LEACH, LEACH-C and EECRP. It is noteworthy that EEICS in terms of the above indicators outperforms than the existing schemes.

An Efficient Cooperative Medium Access Control Protocol for Wireless IoT networks in Smart World System

In recent years, the Internet of Things (IoT) has become the key enabler for Smart World System (SWS). In SWS environment, the IoT is empowering wireless devices/objects with abilities of sensation and communication with each other via Internet and providing simplified, more efficient, and enjoyable lifestyle. However, efficient communication between various wireless devices in IoT network is very important, especially in long distant wireless transmission case. Cooperative Medium Access Control (MAC) protocols for wireless networks supporting the IoT is becoming popular to handle this issue. It considers several metrics, e.g., SNR (Signal to Noise Ratio), delay and residual energy. Nowadays, distance metric has appended a new dimension in the relay selection metric list for Cooperative MAC. Howsoever, protocols that have used distance metric can be optimized further in selecting a relay node by considering reliability. Hence, targeting to optimize relay selection for designing a cooperative MAC protocol, we have proposed a Reliability-based Distance-aware Data-rate-adaptive Cooperative MAC for wireless IoT networks. For the assurance of unfailing and cooperative data transmission, this work strengthens the most suitable relay node selection using a cooperative reliability factor. Distance and residual energy are also used to ascertain that the position of optimal relay possess superior rates. Extensive simulation results demonstrate that proposed reliability-based optimal relay selection as well as MAC operation significantly improves the performance over the existing ones.

Analysis of Joint Relay Selection and Resource Allocation Scheme for Relay-Aided D2D Communication Networks

Device-to-device (D2D) communications, as one of the promising technology for the future network, allow two devices in proximity to communicate directly with each other to alleviate the data traffic load for the base station (BS). In this paper, we analysis the joint relay selection and resource allocation scheme for relay-aided D2D communication networks. The objective is to maximize the total transmission data rates of the system while guaranteeing the minimum quality of service (QoS) requirements for both cellular users (CUs) and D2D users (DUs). We first propose a social-aware relay selection algorithm with low computational complexity to obtain the suitable relay nodes (RNs) for D2D links. Then the power control schemes are considered when a D2D link works in the D2D direct or relay mode to maximize the system transmission data rates. On basis of this, we propose a greedy-based mode selection and channel allocation algorithm, which can not only allocate the appropriate channel resource for D2D links, but also select the optimal communication mode for them. Numerical results demonstrate that the proposed scheme is capable of substantially improving the performance of the system compared with the other algorithms.

FCNS: A Fuzzy Routing-Forwarding Algorithm Exploiting Comprehensive Node Similarity in Opportunistic Social Networks

At the dawn of big data and 5G networks, end-to-end communication with large amounts of data between mobile devices is difficult to be implemented through the traditional face-to-face transmission mechanism in social networks. Consequently, opportunistic social networks proposed that message applications should choose proper relay nodes to perform effective data transmission processes. At present, several routing algorithms, based on node similarity, attempt to use the contextual information related to nodes and the special relationships between them to select a suitable relay node among neighbors. However, when evaluating the similarity degree between a pair of nodes, most existing algorithms in opportunistic social networks pay attention to only a few similar factors, and even ignore the importance of mobile similarity in the data transmission process. To improve the transmission environment, this study establishes a fuzzy routing-forwarding algorithm (FCNS) exploiting comprehensive node similarity (the mobile and social similarities) in opportunistic social networks. In our proposed scheme, the transmission preference of the node is determined through the fuzzy evaluation of mobile and social similarities. The suitable message delivery decision is made by collecting and comparing the transmission preference of nodes, and the sustainable and stable data transmission process is performed through the feedback mechanism. Through simulations and the comparison of social network algorithms, the delivery ratio in the proposed algorithm is 0.85 on average, and the routing delay and network overhead of this algorithm are always the lowest.

Predict and Forward: An Efficient Routing-Delivery Scheme Based on Node Profile in Opportunistic Networks

In the social scene of opportunistic networks, message applications find suitable relay nodes or certain transmission destinations from the surrounding neighbors through specific network addresses of users. However, at the dawn of big data and 5G networks, the variational location information of nodes is difficult to be available to mobile devices all the time, and a long wait for the destination may cause severe end-to-end delay. To improve the transmission environment, this study constructs an efficient routing-delivery scheme (Predict and Forward) based on node profile for the opportunistic networks. The node profile effectively characterizes nodes by analyzing and comparing their attributes instead of network addresses, such as physical characteristics, places of residence, workplaces, occupations or hobbies. According to the optimal stopping theory, this algorithm implements the optimal transmission for Prelearn messages by dividing the complex data transmission process into two different phases (Predict and Forward). Through simulations and the comparison of routing algorithms in opportunistic networks, the proposed strategy increases the delivery ratio by 80% with the traditional methods on average, and the average end-to-end delay in this algorithm is the lowest.

Fragment-based transmission using minimum power consumed routing (FBTMPCR) algorithm of a MIMO integrated MANET

The establishment of an efficient broadcast routing technique in a multiple input multiple output (MIMO)- based mobile ad hoc network is a challenge in wireless communication. MIMO configuration provides enhancement of data throughput even under conditions of interference and multipath fading. Improvement of transmission efficiency by increasing saturation throughput, reducing transmission delay, and minimizing bit error rate is the main motivation of the present work. In this paper a hybrid routing algorithm, fragment-based transmission using minimum power consumed routing, has been developed. It is an integration of the cooperative transmission process and fragmentation of packet payload. The routing algorithm is developed on selecting the best suitable relay node considering effective received signal strength and probability of successful packet transmission. The broadcasting mechanism is done by using multiple fragment of packet transmission through MIMO channel by using a suitable relay node. The performance analysis of this proposed routing algorithm increases the signal to noise interference ratio, resulting in minimization of BER, improvement of saturation throughput, and reduced transmission delay.

An Efficient method for Secure Routing in Delay Tolerant Networks

Delay or Disruption tolerant networks (DTNs) are mobile networks with inherent limitations on network connectivity and topology. There are a number of applications where such networks can be deployed. In extreme situations of lack of connectivity, DTNs nodes stores the messages to the destination and carry it, till it finds and suitable relay node to forward. Most of the existing researchers focused on developing smart relay selection strategies for DTNs. However, the security aspects, such as confidentiality and integrity of the messages being transmitted have been grossly overlooked in the existing DTN routing literature. Hence in this paper, we have addressed the security issues in DTN message forwarding and developed a secure method for message forwarding in DTN. Experimental results show that by incorporating the security features, DTN performance metrics, such as delivery ratio, overhead ratio and delivery delay have been improved compared to traditional routing strategies.

Quantum flower pollination algorithm for optimal multiple relay selection scheme

In order to obtain optimal selection scheme with multiple source-destination pairs and multiple potential relays in cooperative relay networks, an optimal relay selection scheme is designed in cooperative relay networks considering co-channel interference (CCI). It is an integer optimisation problem for selecting suitable relay nodes to obtain optimal system performance. To get the optimal estimation performance with low computing complexity, quantum flower pollination algorithm (QFPA) is proposed to resolve the difficulties of optimal relay selection, and the proposed optimal relay selection scheme is called as quantum flower pollination algorithm based optimal relay selection (QFPA-ORS). The proposed QFPA combines the advantages of quantum evolutionary theory and flower pollination algorithm (FPA). So QFPA has the capability to search the optimal solution. Simulation results show that QFPA based relay selection scheme has the ability to search global optimal solution compared with other relay selection schemes based on classical algorithm and performs better than three other previous intelligent algorithms.

Community Detection Using Inter Contact Time and Social Characteristics Based Single Copy Routing in Delay Tolerant Networks

Delay Tolerant Networks (DTNs) where the node connectivity is opportunistic and end-to-end path between any pair of source and destination is not guaranteed most of the time. Hence the messages are transferred from source to destination via intermediate nodes on hop to hop basis using store-carry-forward paradigm. Due to quick advancement in hand held devices such as smart phone and laptop with support of wireless communication interface carried by human being, it is possible in coming days to use DTNs for message dissemination without setting up infrastructure. The routing task becomes challenging in DTNs due to intermittent network connectivity and the connection opportunity arises only when node comes in transmission range of each other. The performance of the routing protocols depend on the selection of appropriate relay node which can deliver the message to final destination in case of source and destination do not meet at all. Many social characteristics are exhibited by the human being like friendship, community, similarity and centrality which can be exploited by the routing protocol in order to take the forwarding decisions. Literature shows that by using these characteristics, the performance of DTN routing protocols have been improved in terms of delivery probability. The existing routing schemes used community detection using aggregated contact duration and contact frequency which does not change over the time period. We propose community detection through Inter Contact Time (ICT) between node pair using power law distribution where the members of community are added and removed dynamically. We also considered single copy of each message in entire network to reduce the network overhead. The proposed routing protocol named Social Based Single Copy Routing (SBSCR) selects the suitable relay node from the community members only based on the social metrics such as similarity and friendship together. ICTs show power law nature in human mobility which is used to detect the community structure at each node. A node maintains its own community and social metrics such as similarity and friendship with other nodes. Whenever node has to select the relay node then it selects from its community with higher value of social metric. The simulations are conducted using ONE simulator on the real traces of campus and conference environments. SBSCR is compared with existing schemes and results show that it outperforms in terms of delivery probability and delivery delay with comparable overhead ratio.

Cooperative Quantum Key Distribution for Cooperative Service-Message Passing in Vehicular Ad Hoc Networks

Secure message transmission in Vehicular Ad Hoc Networks (VANETs) is a challenging task due to its highly dynamic nature. In VANETs, road side unit (RSU) transmits different types of service messages to those vehicles, who have subscribed for that type of message. Intermediate vehicles, those are not subscribed to that service may also receive the message due to broadcast nature of wireless medium. Current literature on VANETs use conventional cryptography for secure message transmission. In this study, the secure service message delivery in VANETs is modeled as a cooperative quantum key distribution among nodes. In the proposed model, vehicles are interested in using services, that are provided by service providers (SPs) through RSUs after a vehicle registered for that service. A quantum key is distributed to registered vehicle through RSU, which is needed to unlock the service. RSU can transmit the quantum key to the vehicles, which are within its transmission range. A cooperative vehicle helps RSU to transmit the quantum key to a vehicle that is not in its transmission range. A network formation game is modeled for the proposed problem between RSUs and vehicles to form network tree. Vehicles (nodes) use services, work as relay node in-order to cooperate with RSU to relay quantum key. In this paper, a distributed algorithm for cooperative quantum key distribution in VANETs (CQKDVN) is modeled, which helps RSU’s to choose a suitable relay node for quantum key distribution. The proposed algorithm, CQKDVN, helps nodes to decide whether to cooperate with a RSU or not based on the incentive it receives by serving a RSU to deliver quantum key to a destination node. CQKDVN also helps the RSU to adapt to the network topology changes such as a node move out of its range or movement of relay nodes that triggers to switch to a new relay node. CQKDVN constitute the network topology into a Nash network.