Access Layer Research Articles

An Enhanced LoRaWAN Security Protocol for Privacy Preservation in IoT with a Case Study on a Smart Factory-Enabled Parking System.

The Internet of Things (IoT) utilizes algorithms to facilitate intelligent applications across cities in the form of smart-urban projects. As the majority of devices in IoT are battery operated, their applications should be facilitated with a low-power communication setup. Such facility is possible through the Low-Power Wide-Area Network (LPWAN), but at a constrained bit rate. For long-range communication over LPWAN, several approaches and protocols are adopted. One such protocol is the Long-Range Wide Area Network (LoRaWAN), which is a media access layer protocol for long-range communication between the devices and the application servers via LPWAN gateways. However, LoRaWAN comes with fewer security features as a much-secured protocol consumes more battery because of the exorbitant computational overheads. The standard protocol fails to support end-to-end security and perfect forward secrecy while being vulnerable to the replay attack that makes LoRaWAN limited in supporting applications where security (especially end-to-end security) is important. Motivated by this, an enhanced LoRaWAN security protocol is proposed, which not only provides the basic functions of connectivity between the application server and the end device, but additionally averts these listed security issues. The proposed protocol is developed with two options, the Default Option (DO) and the Security-Enhanced Option (SEO). The protocol is validated through Burrows–Abadi–Needham (BAN) logic and the Automated Validation of Internet Security Protocols and Applications (AVISPA) tool. The proposed protocol is also analyzed for overheads through system-based and low-power device-based evaluations. Further, a case study on a smart factory-enabled parking system is considered for its practical application. The results, in terms of network latency with reliability fitting and signaling overheads, show paramount improvements and better performance for the proposed protocol compared with the two handshake options, Pre-Shared Key (PSK) and Elliptic Curve Cryptography (ECC), of Datagram Transport Layer Security (DTLS).

Resource allocation and distributed uplink offloading mechanism in fog environment

Applying fog computing technology to the shared pattern has two problems to cope with. One is to formulate a rational mechanism for resource allocation, and the other is to design computation offloading strategy of tasks based on resource allocation result. For solving these problems, we construct a three-layer F-RAN architecture first, which consists of terminal layer, access layer and network layer. Second, we adopt differential game and bipartite graph multiple matching algorithm to solve bandwidth resource allocation problem of fog node (FN)-access point (AP) and AP-shared terminal (ST), respectively. Third, Lyapunov theory and proposed deviation update decision algorithm (DUDA) are used to solve computation offloading decision-making and offloading update order-making. At last, simulation results show that our strategy can save 30%–60% system consumption, and the resource demand satisfaction rate can be guaranteed to reach 80% or more.

Evaluation of MAC’s Distributed Queuing Algorithm for Internet of Things Applications

<span>Internet of Things and Machine-to-Machine communications have contributed significantly on our daily life. Nevertheless, from the networking aspect they introduced a huge challenge for the performance and quality of services of networks. In this paper, a Distributed Queuing Access for LTE protocol was analyzed to enhance the random access performance for Machine to machine (M2M) applications. The M2M communications presented countless solicitations that can over-burden the access channel of the present LTE network. This prompts to an expansion in the collision probability and results in a noteworthy access delay. The introduced protocol does improve the performance of Medium access layer in terms of blocking probability, access delay, energy utilization and number of re-transmissions attempts in comparison with the standard LTE protocol without altering the existing LTE outline structure. The new protocol is intended to ensure that the random access procedure of the ordinary UE gadget will not be affected bringing about consistent implementation for the proposed convention.</span>

The structural design and technical investigations of data resources sharing system in the field of aero engine

PurposeNowadays, a large amount of data related to aero engine in various types can be created in a single day and it is very important to well organize and store these data. The paper aims to discuss this issue.Design/methodology/approachThis paper puts forward the problem of data management with the fast development of aero engine and sets the compression system as an example to see the inner relationships of data from the initial design procedure to the final operation and maintenance part. There are five principles, namely digitization, accuracy, normative, integrality and validity, involved in managing the data effectively.FindingsThese data resources arranged according to the five principles can be well organized and better used.Originality/valueAt the end, the top design of aero engine data sharing platform is investigated and five layers including data layer, data access layer, communication layer, business logic layer and application layer are designed and presented to support the platform.

Latency-aware cost optimization of the service infrastructure placement in 5G networks

Under 5G use case scenarios latency is a main challenge that must be addressed, since mission critical environments are mostly delay sensitive. To achieve this goal, the service infrastructure placement optimization is needed in the interest of minimizing the delays in the service access layer. To solve this problem, this paper mathematically models the placement problem in a Fog Computing/NFV environment as a Mixed-Integer Linear Programming problem and proposes a heuristic-based solution considering 5G mobile network requirements. As a practical result, an application was developed to achieve usability and flexibility while ensuring operational applicability of the proposed methods.

Research of the self-healing technologies in the optical communication network of distribution automation

Optical communication network is the mainstream technique of the communication networks for distribution automation, and self-healing technologies can improve the in reliability of the optical communication networks significantly. This paper discussed the technical characteristics and application scenarios of several network self-healing technologies in the access layer, the backbone layer and the core layer of the optical communication networks for distribution automation. On the base of the contrastive analysis, this paper gives an application suggestion of these self-healing technologies.

Attosecond Time Delay in Photoionization of Noble-Gas and Halogen Atoms

Ultrafast processes are now accessible on the attosecond time scale due to the availability of ultrashort XUV laser pulses. Noble-gas and halogen atoms remain important targets due to their giant dipole resonance and Cooper minimum. Here, we calculate photoionization cross section, asymmetry parameter and Wigner time delay using the time-dependent local-density approximation (TDLDA), which includes the electron correlation effects. Our results are consistent with experimental data and other theoretical calculations. The asymmetry parameter provides an extra layer of access to the phase information of the photoionization processes. We find that halogen atoms bear a strong resemblance on cross section, asymmetry parameter and time delay to their noble-gas neighbors. Our predicted time delay should provide a guidance for future experiments on those atoms and related molecules.

Performance evaluation under an AFR scheme CSMA/CA for HomePlug AV supported in Bianchi�s Model

Background/Objectives: HPAV uses a new retransmission model of lost packages called Aggregation with Fragment Retransmission (AFR), which utilizes CSMA/CA as a mechanism to accessing the media. The main purpose of this paper is to assess the performance of a network supported in HPAV standard under the scheme AFR. Methods/Statistical Analysis: In this paper, the concept of saturation of throughput will be used for a finite number of stations. For that matter, it is necessary to assume that the size of the package is fixed of bits to a rate of Mbps. Additionally, an adaptation to Bianchi’s model was carried out adjusted to the MAC structure of HPAV, which allows to represent CSMA/CA as a Markov’s chain in discrete time of two dimensions. All this is done in order to represent the back-off procedure under a scheme DCF with saturated stations. Relevance of the Subject: AFR is a scheme that was proposed in order to achieve a high efficiency in the control layer of media access (MAC), based on CSMA/CA, and that, to date, has only been considered in Wireless networks supported in 802.11n. To date, similar works have not yet been found applicable to HPAV in the vast bibliographic sources. Results: Based on the obtained results, it was possible to observe that the model allows to assess the probability of lost packages, the MAC efficiency, the throughput and the delay levels in a PLC network, under a scheme AFR, subject to the number of stations, the size of the containment window and bandwidth available in the channel. Application/ Improvements: It is recommended to carry out similar studies under the use of TDMA over HPAV for the voice and video broadcasting, having into account that HPAV uses a mechanism of accessing to the hybrid media in order to offer adequate levels of QoS. Keywords: HomePlug, Performance, Powerline, Throughput, AFR, CSMA/CA

Synchronisation algorithm for OFDM/OQAM systems based on zero autocorrelation code

In this study, the authors first propose a sequence with the impulse-like autocorrelation property named zero autocorrelation code (ZAC) for orthogonal frequency division multiplexing (OFDM) based on offset quadrature amplitude modulation (OQAM) systems. The ZAC sequence can be generated by many prototype filters such as physical layer for dynamic spectrum access and cognitive radio and isotropic orthogonal transform algorithm filters. Thus, it has a wide application range. The authors then propose a synchronisation algorithm based on the ZAC. The proposed algorithm only needs two symbols to compose the preamble while existing algorithms need at least four symbols. They further assess the synchronisation performances via computer simulation. The simulation results show that the proposed algorithm can achieve better performance in terms of root mean square error of the timing and frequency offset estimation, with a 10 dB improvement on timing offset estimation performance over Saeedi-Sourck's algorithm when signal-to-noise ratio is 0 dB.

Average PSNR Optimized Cross Layer User Grouping and Resource Allocation for Uplink MU-MIMO OFDMA Video Communications

Wang et al. proposed cross layer resource allocation according to the channel state information of the physical layer and the video rate distortion of the application layer for uplink orthogonal frequency division multiple access (OFDMA) video transmission systems. Its object function is minimizing sum of all users’ video distortion. It shows significant improvement in average peak-signal-to-noise-ratio (PSNR) over the schemes which consider either the physical layer or application layer. However, minimizing sum of all users’ video distortion does not necessarily maximize average of all users’ PSNR. In this paper, we change the objective function for optimization to maximize average PSNR, and derive new optimal condition for cross layer subcarrier assignment for infinitesimal bandwidth increment. Furthermore, we extend to a multi-user multiple-input and multiple-output (MU-MIMO) uplink transmission system to improve information rate and thus video quality. We then propose an average PSNR optimized physical/application cross-layer user grouping and resource allocation for uplink MU-MIMO OFDMA video communications. The simulation results show that the proposed scheme has 4 dB PSNR gain over the previous Wang et al. cross-layer scheme and 5 dB PSNR gain over the previous physical layer only scheme for four users and SNR 12–18 dB.

Performance Comparison of RIPv2 and DSR Protocols in Customized Zigbee Stack with 5 Nodes and 1HOP

Wireless sensor network (WSN) is a collection of different sensor nodes communicating with each other in a mesh network to improve reliability and prevent link failures. WSN is suffering with scarcity of resources like memory, data rates, throughput and others. WSN integrated with IP can lead to many applications and enables any electronic device to access different networks and use the commonly shared resources. IP stack is not suitable to be ported into the memory of WSN node as it occupies more memory and causes more overhead to WSN. In order to realise such a challenging concept, an experiment is carried out such that a new stack is proposed with middleware, by incorporating different protocol sets in network layer and medium access control (MAC) layers of Zigbee stack. Routing Information Protocol (RIP) and Dynamic Source Routing (DSR) protocols are ported in the network layer of Zigbee stack and Carrier Sense Multiple Access (CSMA) protocol ported in the MAC layer of Zigbee stack while keeping the other layers of the Zigbee stack unchanged. Experimentation results of RIP–CSMA and DSR–CSMA protocol sets are compared and published in this paper.

Developing a Network Security Intelligence Center

In this paper, continuing our research on designing a Network Security Intelligence Center (NSIC) as a combination of a Security Intelligence Center and a Network Operations Center, we applied the PDCA approach to its development in accordance with the requirements, which we formulated for its operations and self-protection. Following the Plan stage of this approach, we proposed a five-layered NSIC’s infrastructure (including platform, software, service delivery, access and management layers) and its high-level zone security infrastructure with four zones: demilitarized, trusted, restricted and management zones. All of them are briefly described in the paper. The main area of short-term further work concludes the paper.

Reliable wireless MAC layer for industrial internet of things using polarisation diversity

Industrial internet of things (IIoT) requires superior reliability from underlying communication technology that consumer wireless technologies often fail to meet. Utilising polarisation diversity techniques through rotating polarisation waves (RPWs) have been recently proposed to improve the coverage and reliability of IIoT network. However, the design of medium access (MAC) layer that optimally utilises the key features of the underlying physical layer is a key challenge especially when considering multihop networks. Adopting conventional MAC protocols based on carrier sensing or time division alone would not utilise the physical layer in its optimal manner leading to lower throughput and higher end-to-end latency. In this paper, novel medium access techniques to improve the reliability in the RPW wireless communication have been described. We also consider extensions to the MAC layer to support multihop network using the tree topology. An overview of MAC layer methods and comparative mathematical analysis is provided that clearly show the benefits of multi-hop RPW over conventional networks.

A Robust Dynamic Edge Network Architecture for the Internet of Things

A massive number of devices are expected to fulfill the missions of sensing, processing and control in cyber-physical Internet-of-Things (IoT) systems with new applications and connectivity requirements. In this context, scarce spectrum resources must accommodate a high traffic volume with stringent requirements of low latency, high reliability and energy efficiency. Conventional centralized network architectures may not be able to fulfill these requirements due to congestion in backhaul links. This article presents a novel design of a robust dynamic edge network architecture (RDNA) for IoT which leverages the latest advances of mobile devices (e.g., their capability to act as access points, storing and computing capabilities) to dynamically harvest unused resources and mitigate network congestion. However, traffic dynamics may compromise the availability of terminal access points and channels and, thus, network connectivity. The proposed design embraces solutions at physical, access, networking, application, and business layers to improve network robustness. The high density of mobile devices provides alternatives for close connectivity which reduces interference and latency, and thus, increases reliability and energy efficiency. Moreover, the computing capabilities of mobile devices project smartness onto the edge which is desirable for autonomous and intelligent decision making. A case study is included to illustrate the performance of RDNA. Potential applications of this architecture in the context of IoT are outlined. Finally, some challenges for future research are presented.

On Uplink Virtual MIMO with Device Relaying Cooperation Enforcement in 5G Networks

In this paper, a novel protocol is proposed in which mobile terminals (MT) form a virtual Multiple-input Multiple-output (MIMO) uplink by means of device relaying on Device to Device (D2D) tier in 5G Cellular Network. The competitive scenario is considered in which each of the selfish MTs tries to transmit its own data and not relay others’ data in the formed virtual MIMO. The main focus is to design an incentive for MTs to form the virtual MIMO and cooperate in relaying others data. A direct revelation on-line mechanism for the BS is designed, in order to assist forming a stable virtual MIMO. A self-punishment mechanism is also proposed in which MTs autonomously punish malicious MTs that do not cooperate in relaying. We prove that our designed direct revelation on-line mechanism and proposed self-punishment mechanism enforce all-cooperation (all-C) profile as a Nash equilibrium (NE), under uncertainty in the presence of MTs in the formed virtual MIMO. Our simulation results confirm that the proposed protocol, even in the competitive scenario, increases the bit rate and decreases power consumption at the same time. The proposed protocol can improve the energy efficiency up to 35 percent compared to a non-cooperative case, i.e., Single-Input Multiple-Output (SIMO) uplink. Moreover, if the multi-user MIMO transmission is used for the uplink medium access layer, the proposed protocol can improve the energy efficiency up to 42 percent compared to SIMO uplink with multi-user MIMO transmission. Under the proposed OCVM protocol with Shapley value fairness, the price of anarchy reaches to 0.78 in the competitive scenario. In addition, the energy efficiency improvement of our proposed protocol is almost robust to the preferences of MTs. Simulation results show that if BS employs our on-line mechanism and MTs autonomously punish malicious MTs, the malicious MTs cannot gain by defecting from relaying other MTs’ data.

Smart Query Optimization Approach In Distributed Environment

On a distributed enterprise scale, the information is stretched among heterogenous sites and treated always separately. Searching through different sites may become a difficult task due to the context variation between the distributed system nodes. We propose in this paper a high level access layer with a semantic analysis ability, an index semantic summary. This layer is intended to optimize the bandwidth consumption and reduce the local search engines effort. This component also enhances the quality of the search results by using the Word Mover Distance to fetch semantically close results.

An Approach for Enhancing Data Access Security in Heterogeneous Database Systems

Objectives: This paper proposes an enhanced data access security approach to allow virtual private database security mechanism in heterogeneous multi-tier applications regardless of the data access security features provided by each database management system. Methods/Statistical Analysis: An implementation of Data Access Layer has been done respecting the proposed approach. This implementation enhances Microsoft’s Entity Framework that is widely used in commercial multi-tier database applications as a Data Access Layer. Accordingly, it’s overloaded by the required functionality including query modification and data validation. The output assembly then is tested in a typical HR database application that targets three different DBMS’s (SQL Server, MySQL, Oracle) with exactly same database state. A time measurement takes place to evaluate the processing cost of issuing CRUD operations compared with the same application architecture without using the proposed approach (e.g. relying on the row-level security provided by Oracle on the DBMS level). Findings: An illustrated case study respecting the proposed approach shows its scalability, reliability and efficiency. It allows data access security in both homogenous and heterogeneous database applications. On the other hand, the results show that the cost of processing both of data retrieval and data manipulation operations respecting predefined data access security policies of the proposed approach compared with Oracle VPD are reduced by around 59% and 57% respectively. Application/Improvements: As presented in the illustrative case study, the proposed approach can be easily applied and reused in any modern heterogeneous multi-tier database application. It allows defining data access security policies regardless of the target database management system type. Also, the results show an improvement in the processing cost of the proposed approach compared with the Oracle virtual private database with both data retrieval and data manipulation operations. Keywords: Data Privacy; Data Access; Database; Heterogeneous Database Applications

Research on Application of Wireless Bridge Technology in the Smart Grid

The construction of smart grid, in the meet of communication network core layer must have the strong bearing capacity and the strong network frame, also requires the access layer have the wide variety and flexible edge access ability. In this article, in accordance with the technical features of the smart grid communication network, combined with the Global Energy Interconnection to the requirement of all kinds of communication. The wireless bridge system based on the IEEE 802.11 series protocol as flexible edge access is applied to the smart grid communications, to forward the power wireless bridge structure design and the bridge monitoring management platform design and safety protection design. The use of a wireless bridge will increase the transmission quality of signal, distance and the safety of the transmission. In this article, the wireless bridge in the application of the smart grid electric power communication network has a role in promoting, has a guiding significance to the construction of the smart grid communication.

Long-short range communication network leveraging LoRa™ and wake-up receiver

Wireless sensor and actuator networks play a central role in the Internet of Things, and a lot of effort is devoted to enable energy efficient and low latency communications. In the recent years, low power communications has evolved towards multi-kilometer ranges and low bit-rate approaches such as LoRa™. However, the medium access layer protocols rely on the well-known duty-cycling schemes, which require a trade-off between power consumption and latency for message transfer from the gateway to the nodes. Domains such as industrial applications in which sensors and actuators are part of the control loop require predictable latency, as well as low power consumption. Emerging ultra-low-power wake-up receivers enable pure-asynchronous communications, allowing both low latency and low power consumption, but at the cost of a lower sensitivity and lower range than traditional wireless receivers and LoRa™. In this work, we propose an energy efficient architecture that combines long-range communication with ultra low-power short-range wake-up receivers to achieve both energy efficient and low latency communication in heterogeneous long-short range networks. A hardware architecture as well as a protocol is proposed to exploit the benefits of these two communication schemes. Experimental measurements and analytical comparisons show that the proposed approach remove the need for a trade-off between power consumption and latency.

Cross-Layer Power Allocation in Nonorthogonal Multiple Access Systems for Statistical QoS Provisioning

Power allocation is a critical issue in the physical layer of power-domain nonorthogonal multiple access (NOMA) systems. However, existing power allocation schemes have not considered the delay quality of service (QoS) requirement in the datalink layer of users, and hence may not ensure the desired delay QoS requested by the services in the upper layers. Different from existing works, we apply the statistical QoS theory into NOMA systems and formulate the physical-datalink cross-layer power allocation problem as a stochastic optimization problem under different delay QoS constraints. Also, we show that the formulated problem is quasi-concave and propose a bisection-based cross-layer power allocation algorithm. Simulation results show that the proposed algorithm is able to converge to the optimal solution obtained by exhaustive search. Also, the proposed scheme outperforms existing fixed NOMA and time-division multiple access based schemes in terms of max–min effective capacity.