Medium Access Layer Research Articles

Performance Evaluation of Asynchronous Multi-channel MAC Protocol for WSN

Wireless sensor networks enable a variety of application scenarios due to their flexibility, the wide range of hardware solutions, as well as their simplicity. However, new challenges arise that make applications viable, such as power consumption, robust communication, limited storage and processing. One of the main elements among communication and power consumption optimization aspects is related to the protocol stack and especially the medium access layer, due to the nature of the wireless environment. Thus, this article proposes a multi-channel mechanism for asynchronous receiver-initiated MAC for low-power WSN. The proposed protocol reduces energy consumption due to message contention and idle listening through an initial recognition mechanism and an efficient multichannel mechanism based on knowledge of the best channel in each node of the network. For validation of the protocol, evaluations were made for consumption, latency and rate of delivery of the network in a web application, comparing the multichannel asynchronous protocol to the synchronous protocol. The results show that the synchronous protocol presents slight superiority in communication performance, whereas the asynchronous protocol presents lower consumption.

Event-Driven Data Gathering in Pure Asynchronous Multi-Hop Underwater Acoustic Sensor Networks.

In underwater acoustic modem design, pure asynchrony can contribute to improved wake-up coordination, thus avoiding energy-inefficient synchronization mechanisms. Nodes are designed with a pre-receptor and an acoustically adapted Radio Frequency Identification system, which wakes up the node when it receives an external tone. The facts that no synchronism protocol is necessary and that the time between waking up and packet reception is narrow make pure asynchronism highly efficient for energy saving. However, handshaking in the Medium Control Access layer must be adapted to maintain the premise of pure asynchronism. This paper explores different models to carry out this type of adaptation, comparing them via simulation in ns-3. Moreover, because energy saving is highly important to data gathering driven by underwater vehicles, where nodes can spend long periods without connection, this paper is focused on multi-hop topologies. When a vehicle appears in a 3D scenario, it is expected to gather as much information as possible in the minimum amount of time. Vehicle appearance is the event that triggers the gathering process, not only from the nearest nodes but from every node in the 3D volume. Therefore, this paper assumes, as a requirement, a topology of at least three hops. The results show that classic handshaking will perform better than tone reservation because hidden nodes annulate the positive effect of channel reservation. However, in highly dense networks, a combination model with polling will shorten the gathering time.

Towards Industrial Ultra-Wideband Networks: Experiments for Machine Vibration Monitoring

We discuss the potential of ultra-wideband (UWB) technology for realizing use cases in industry 4.0 and demonstrate the implementation of an UWB sensor network with off-the-shelf transceivers for machine vibration monitoring. We propose a flexible medium access layer tailored for industrial sensing and show how the choice of its parameters is affected by the propagation environment and hardware constraints. Our real-world experiments reveal that links up to 20 meters can be achieved in industrial environments with an average packet loss rate in the order of 10 -6 for typical links. A comparison with a commercial vibration monitoring system based on IEEE 802.15.4 spread spectrum shows that UWB attains a twenty-times higher throughput for similar link ranges.

Interference Mitigation of Heterogeneous Cognitive Radio Network using Spatial Diversity

The heterogeneous cognitive radio networks are playing the most important role in the future generation wireless networks in order to address the problem of spectrum scarcity and to satisfy the demand of multiple coexistence networks. . In a country like India the deployment of CRN is possible on television network with the help of TV White Spaces (TVWS) as its capacity is quite high due to digital transmission of TV channel. The use of multiple wireless standards such as IEEE 802.11a, IEEE 802.22, IEEE 802.19.1 and many more wireless networks operating in the same frequency band of TVWS creates the coexistence scenario which involves the heterogeneous networks. The interference mitigation is the most important issue in such heterogeneous networks. In literature, the issue of interference mitigation is addressed mainly at the medium access layer; however, very limited work is presented at physical layer. In this paper, an interference mitigation problem of heterogeneous cognitive radio network at physical layer is addressed. The spatial diversity based techniques are proposed to mitigate the interference in heterogeneous CRN. The coexistence of different wireless networks in secondary CRN is considered for analysis. The characterization of aggregate interference is carried out for different interference scenarios. The proposed system outperform for heterogeneous CRN network over TVWS network.

Improving Route Selections in ZigBee Wireless Sensor Networks.

The ZigBee wireless communication specifications forecast the use of multihop routes between nodes and define that nodes select their routes based on their costs. The specifications define how to compute a route cost from the probability of successfully transmitting on each of the routes’ links; and it is recommended that such probabilities be obtained by counting received link status messages or averaging link quality indicators from received packets. In this paper, we study the performance of these two recommended procedures, show that they can lead to degraded route selections, and propose a procedure that can improve route selections without modifications to the ZigBee protocol or frame formats. Our procedure estimates the probability of successful transmission on each link, based on information from the medium access layer during unicast packet transmissions, and includes a modification into how ZigBee nodes treat routing messages internally in order to reduce variations in the link cost estimates. Focusing on a home environment with one or two hops, our simulation results show that, in several scenarios, our procedure performs better than either of the two procedures recommended in the ZigBee specifications.

Novel Schemes to prioritize the TCP ACK for throughput improvement in B4G and 5G networks

Evolution in cellular wireless communication and standardization has brought out technological advancements in physical and medium access (MAC) layer protocol to scale the data rate on the air interface like in Long Term Evolution (LTE) or New Radio (NR) 3GPP standards, by 10X to 100X compared to ol

Attack-Aware Dynamic Upstream Bandwidth Assignment Scheme for Passive Optical Network

Abstract Network security is an important component of today’s networks to combat the security attacks. The passive optical network (PON) works at the medium access layer (MAC). A distributed denial of service (DDOS) attack may be launched from the network and transport layers of an Optical Network unit (ONU). Although there are various security techniques to mitigate its impact, however, these techniques cannot mitigate the impact on the MAC Layer of the PON and can cause an ONU to continuously drain too much bandwidth. This will result in reduced bandwidth availability to other ONUs and, thus, causing an increase in US delays and delay variance. In this work we argue that the impact of a DDOS attack can be mitigated by improving the Dynamic bandwidth assignment (DBA) scheme which is used in PON to manage the US bandwidth at the optical line terminal (OLT). The present DBA schemes do not have the capability to combat a security attack. Thus, this study, uses a machine learning approach to learn the ONU traffic demand patterns and presents a security aware DBA (SA-DBA) scheme that detects a rogue (attacker) ONU from its traffic demand pattern and limits its illegitimate bandwidth demand and only allows it the bandwidth assignment to it as per the agreed service level agreement (SLA). The simulation results show that the SA-DBA scheme results in up to 53%, 55% and 90% reduced US delays and up to 84%, 76% and 95% reduced US delay variance of T2, T3 and T4 traffic classes compared to existing insecure DBA schemes.

Packet size impact on the 802.11 network performances

The 802.11 performances degrade significantly when many access points are deployed within the same interfering area. New series of 802.11x are deployed and other alternative technologies, such as WiMAX, are exist. However, as 802.11 devices are widely deployed, existing technology optimization is less expensive than new technology deployment. This paper reports simulation evaluations of 802.11 performance enhancement by increasing 802.11 packet size. The increasing size can be performed within medium access layer or within transport layer through buffering schemas. The assessment shows that by doubling the packet size, the media access delay in 802.11b can be reduced up to 61%, throughput is increased up to 2.16%, and network utility is maximized up to 2.25 %.

Processing efficient frame structure for passive optical network (PON)

The time division multiplexed (TDM) based passive optical networks like GPON/XGPON and EPON/10G-EPON use broadcast mechanism for downstream (DS) communication. This results in any DS frame being received and processed by all optical network units (ONUs), leading to significant processing energy wastage. Specifically, the ITU compliant PONs (GPON/XGPON) frame structure further aggravates this problem due to its inefficient frame structure and synchronous nature which requires sending of DS frames every 125 μs. This frame structure requires an ONU to completely process every DS frame completely, even if it is not destined for it. The bit interleaved PON (Bi-PON) resolves this problem by changing the frame structure to a bit interleaved pattern and introduce a decimator unit that enables an ONU to tune to its concerned bits only. However, due to additional hardware requirement, this solution is not applicable to current ONU architecture. Consequently, this study presents a processing efficient version of GPON frame that helps an ONU to identify an unrelated DS frame at its start and thus discard it without complete processing. A processing efficient strategy for the medium access layer (MAC) processor of an ONU is also presented. The simulation results show a processing energy saving of 88%, 89% and 89.47% with proposed frame structure for a split ratio of 16, 32 and 64 respectively.

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>

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.

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.

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.

Study and overview on WBAN under IEEE 802.15.6

WBAN (wireless body area networks) is an upcoming technology which stands to be a base for wearable and implantable sensors. The IEEE 802.15.6 formulates the physical and medium access for body area networks. The Body area networks can be implemented in several applications like health monitoring, ambient living environments and consumer electronics. This paper gives a clear overview about the functions of WBAN. The medium access layers and the physical layers of IEEE 802.15.6 are deeply examined and studied in this work. The access mechanisms of the protocol are explained in this paper. A clear literature review has also been stated to know the current state of art of this technology. The future possibilities and area to be explored also has been defined in this work.

A subjective scheduler for subjective dedicated networks

Multiple access technique is one of important techniques within medium access layer in TCP/IP protocol stack. Each network technology implements the selected access method. Priority can be implemented in those methods to differentiate services. Some internet networks are dedicated for specific purpose. Education browsing or tutorial video accesses are preferred in a library hotspot, while entertainment and sport contents could be subjects of limitation. Current solution may use IP address filter or access list. This paper proposes subjective properties of users or applications are used for priority determination in multiple access techniques. The NS-2 simulator is employed to evaluate the method. A video surveillance network using WiMAX is chosen as the object. Subjective priority is implemented on WiMAX scheduler based on traffic properties. Three different traffic sources from monitoring video: palace, park, and market are evaluated. The proposed subjective scheduler prioritizes palace monitoring video that results better quality, xx dB than the later monitoring spots.

Location based transmission using a neighbour aware with optimized EIFS MAC for ad hoc networks

In a typical Ad Hoc network, participating nodes have scarce shared bandwidth and limited battery life resources, so resource optimization and enhancing the overall network performance are the primary aims to maintain functionality. This paper proposes a new cross layer Medium Access Control (MAC) algorithm called Location Based Transmission using a Neighbour Aware with optimized Extended Inter-Frame Spacing (EIFS) for Ad Hoc Networks MAC (LBT-NA with optimized-EIFS MAC) that aims to reduce the transmission power when communicating with the next hop receiver based on node's location which is made available during node deployment. However, node mobility is not taken into account in the study of this paper. According to the algorithm the node dynamically adjusts its transmission power, if there is an active neighbour located beyond the communicating source and destination pair to avoid hidden nodes. The new protocol also defines an optimized EIFS when frame collision, frame error or frame capture takes place, in-order to maintain a fair channel access among the contending nodes. The proposed MAC also uses a modified range of random backoff values, based on the degree of contention unlike IEEE 802.11 series which uses a fixed random backoff value for fresh frames irrespective of the degree of contention. Simulation results indicate that in a random topology with a random source and destination, when the two sources are separated by a minimum distance of 200m, the performance gain of power controlled MAC over IEEE 802.11b ranges from 30% to 70% depending on the type of traffics in the network and the degree of fairness ranges from 62% to 99.99% for a location based MAC with minimum power transmission, whereas LBT-NA with optimized-EIFS MAC secures fairness index ranging from 75% to 99.99%. Communication with a node that is 20m away can save 40% of the battery life in comparison to the traditional transmission power MAC from 802.11b. The validation tests demonstrate that the proposed algorithm increases battery life and reduces the interference impact on shorter distance communication and increases the probability of parallel transmission. The proposed protocol also provides a scope for active nodes to transmit with a higher degree of probability, providing higher degree of overall network throughput in the environment and alleviate the starvation of hidden node by using Dynamic EIFS scheme.

Automatic design of fuzzy logic controllers for medium access control in wireless body area networks – An evolutionary approach

Soft computing techniques including fuzzy logic have been successfully applied to wireless body area networks (WBANs). However, most of the existing research works rely on manual design of the fuzzy logic controller (FLC). To address this issue, in this paper, we propose an evolutionary approach to automate the design of FLCs for cross layer medium access control in WBANs. With the goal of improving network reliability while keeping the communication delay at a low level, we have particularly studied the usefulness of three coding schemes with different levels of flexibility during the evolutionary design process. The influence of fitness functions that measure the effectiveness of each possible FLC design has also been examined carefully in order to achieve a good balance between reliability and performance. Moreover, we have utilised surrogate models to improve the efficiency of the design process. In consideration of practical usefulness, we have further identified two main design targets. The first target is to design effective FLCs for a specific network configuration. The second target focuses on designing FLCs to function across a wide range of network settings. In order to examine the usefulness of our design approach, we have utilised two widely used evolutionary algorithms, i.e. particle swarm optimisation (PSO) and differential evolution (DE). The FLC designed by our approach is also shown to outperform some related algorithms as well as the IEEE 802.15.4 standard.

Physical layer architectures for machine type communication networks—a survey

AbstractMachine‐type communication (MTC) has attracted much attention due to the fact that it provides pervasive connections for billions of MTC devices, forming a basis for the Internet of things. Most works in the literatures on machine‐to‐machine (M2M) communications focused on media access layer (MAC) layer or other upper layer applications, such as e‐health, energy management and entertainment services. On the other hand, physical (PHY) layer plays a pivotal role in M2M communications. To accommodate a large number of MTC devices, M2M should be made efficient enough in terms of its power consumption and spectrum utilisation. Copyright © 2016 John Wiley & Sons, Ltd.

Mobility and Network Selection in Heterogeneous Wireless Networks: User Approach and Implementation

The Intelligent Transport Systems (ITS) wireless infrastructure needs to support various safety and non-safety services for both autonomous and non-autonomous vehicles.The existing wireless infrastructures can already be used for communicating with different mobile entities at various monetary costs.A packet scheduler, included in a shim layer between the network layer and the medium access (MAC) layer, which is able to schedule packets between uncoordinated Radio Access Technologies (RATs) without modification of the wireless standards, has been devised and its performance evaluated.In this paper, we focus on the influence of mobility type in heterogeneous wireless networks.Three cases are considered based on the mobility in the city: walking, cycling, and driving. Realistic simulations are performed by generating mobility traces of Oxford from Google Maps and overlaying the real locations of existing WiFi Access Points. Results demonstrate that the shim layer approach can accommodate different user profiles and can be a useful abstraction to support Intelligent Transport Systems where there is no coordination between different wireless operators.

State of the Art in Power Line Communications: From the Applications to the Medium

In recent decades, power line communication has attracted considerable attention from the research community and industry, as well as from regulatory and standardization bodies. In this article we provide an overview of both narrowband and broadband systems, covering potential applications, regulatory and standardization efforts and recent research advancements in channel characterization, physical layer performance, medium access and higher layer specifications and evaluations. We also identify areas of current and further study that will enable the continued success of power line communication technology.