Standard MAC Protocol Research Articles

Enhanced Beacons Dynamic Transmission over TSCH

Time slotted channel hopping (TSCH) has become the standard multichannel MAC protocol for low-power lossy networks. The procedure for associating nodes in a TSCH-based network is not included in the standard and has been defined in the minimal 6TiSCH configuration. Faster network formation ensures that data packet transmission can start sooner. This paper proposes a dynamic beacon transmission schedule over the TSCH mechanism that achieves a shorter network formation time than the default minimum 6TiSCH static schedule. A theoretical model is derived for the proposed mechanism to estimate the expected time for a node to get associated with the network. Simulation results obtained with different network topologies and channel conditions show that the proposed mechanism reduces the average association time and average power consumption during network formation compared to the default minimal 6TiSCH configuration.

Enabling Energy Harvesting-Based Wi-Fi System for an e-Health Application: A MAC Layer Perspective.

The adverse impacts of using conventional batteries in the Internet of Things (IoT) devices, such as cost-effective maintenance, numerous battery replacements, and environmental hazards, have led to an interest in integrating energy harvesting technology into IoT devices to extend their lifetime and sustainably effectively. However, this requires improvements in different IoT protocol stack layers, especially in the MAC layer, due to its high level of energy consumption. These improvements are essential in critical applications such as IoT medical devices. In this paper, we simulated a dense solar-based energy harvesting Wi-Fi network in an e-Health environment, introducing a new algorithm for energy consumption mitigation while maintaining the required Quality of Service (QoS) for e-Health. In compliance with the upcoming Wi-Fi amendment 802.11be, the Access Point (AP) coordination-based optimization technique is proposed, where an AP can request dynamic resource rescheduling along with its nearby APs, to reduce the network energy consumption through adjustments within the standard MAC protocol. This paper shows that the proposed algorithm, alongside using solar energy harvesting technology, increases the energy efficiency by more than 40% while maintaining the e-Health QoS requirements. We believe this research will open new opportunities in IoT energy harvesting integration, especially in QoS-restricted environments.

How Can Wake-up Radio Reduce LoRa Downlink Latency for Energy Harvesting Sensor Nodes?

LoRa is popular for internet of things applications as this communication technology offers both a long range and a low power consumption. However, LoRaWAN, the standard MAC protocol that uses LoRa as physical layer, has the bottleneck of a high downlink latency to achieve energy efficiency. To overcome this drawback we explore the use of wake-up radio combined with LoRa, and propose an adequate MAC protocol that takes profit of both these heterogeneous and complementary technologies. This protocol allows an opportunistic selection of a cluster head that forwards commands from the gateway to the nodes in the same cluster. Furthermore, to achieve self-sustainability, sensor nodes might include an energy harvesting sub-system, for instance to scavenge energy from the light, and their quality of service can be tuned, according to their available energy. To have an effective self-sustaining LoRa system, we propose a new energy manager that allows less fluctuations of the quality of service between days and nights. Latency and energy are modeled in a hybrid manner, i.e., leveraging microbenchmarks on real hardware platforms, to explore the influence of the energy harvesting conditions on the quality of service of this heterogeneous network. It is clearly demonstrated that the cooperation of nodes within a cluster drastically reduces the latency of LoRa base station commands, e.g., by almost 90% compared to traditional LoRa scheme for a 10 nodes cluster.

Intelligent CW Selection Mechanism Based on Q-Learning (MISQ)

Mobile ad hoc networks (MANETs) consist of self-configured mobile wireless nodes capable of communicating with each other without any fixed infrastructure or centralized administration using the medium radio. Wireless technology is based on standard IEEE.802.11. The IEEE 802.11 Distributed Coordination Function (DCF) MAC layer uses the Binary Exponential Backoff (BEB) algorithm to deal with wireless network collisions. BEB is considered effective in reducing the probability of collisions but at the expense of numerous network performance measures, such as throughput and packets delivery ratio, mainly in high traffic load. Deep Reinforcement Learning (DRL) is a DL technique in which an agent can achieve a goal by interacting with the environment. In this paper, using one of the DRL models, we propose Q-learning (QL) to optimize MAC protocols' performance based on the contention window (CW) in MANETs. The intelligent proposed MISQ takes into account the number of packets to be transmitted and the collisions committed by each station to select the appropriate contention window. The performance of the proposed mechanism is evaluated by using in-depth simulations. The outputs indicate that the intelligent proposal mechanism learns various MANETS environments and optimizes performance over standard MAC protocol. The performance of MISQ is evaluated in various networks with throughput, channel access delay, and packets delivery rate as performance measures.

Reputation Management Using Honeypots for Intrusion Detection in the Internet of Things

Internet of Things (IoT) networks consist of tiny devices with limited processing resources and restricted energy budget. These devices are connected to the world-wide web (www) using networking protocols. Considering their resource limitations, they are vulnerable to security attacks by numerous entities on the Internet. The classical security solutions cannot be directly implemented on top of these devices for this reason. However, an Intrusion Detection System (IDS) is a classical way to protect these devices by using low-cost solutions. IDS monitors the network by introducing various metrics, and potential intruders are identified, which are quarantined by the firewall. One such metric is reputation management, which monitors the behavior of the IoT networks. However, this technique may still result in detection error that can be optimized by combining this solution with honeypots. Therefore, our aim is to add some honeypots in the network by distributing them homogeneously as well as randomly. These honeypots will team up with possible maliciously behaving nodes and will monitor their behavior. As per the simulation results, this technique reduces the error rate within the existing IDS for the IoT; however, it costs some extra energy. This trade-off between energy consumption and detection accuracy is studied by considering standard routing and MAC protocol for the IoT network.

Emergency Vital Data Packet Transmission in Hospital Centered Wireless Body Area Network

Abstract The paper presents delay analysis of emergency vital data packets (EVDP) in the hospital centered wireless body area network (HCWBAN). In the proposed HCWBAN the sensor nodes, ZigBee enabled, are responsible for monitoring the vital parameters of human body such as body temperature, blood pressure, heart rate, electrocardiogram and electroencephalogram. The sensed vital parameters are accumulated at a center node and send the vital parameters data packets to Personal Area Network (PAN) coordinator. The vital data packets are classified as normal vital data packets and emergency vital data packets. The normal vital data packets are sent to the Hospital Information System (HIS) using standard ZigBee MAC protocol while for emergency vital data packet handling, modified MAC protocol has been proposed. The comparative analysis of the standard ZigBee MAC protocol and modified MAC protocol is presented at the end of the paper for delay analysis for normal and emergency vital data packet transmission.

ADMC-MAC: Energy efficient adaptive MAC protocol for mission critical applications in WSN

Energy efficient wireless sensor networks play a very important role in mission critical applications, as in these applications it is difficult to deploy and change the nodes frequently or to change their battery. Some of the mission critical applications are healthcare applications, environmental monitoring and control applications (Tsunami alert, earthquake alert, volcanic eruption prone areas) and surveillance applications. These applications require quick response time along with power management, so that the energy efficiency can be achieved without having latency beyond a critical threshold limit. Several MAC protocols have been proposed by researchers with a preview to enhance energy efficiency but hey failed to fulfill the need of mission critical applications. An in-depth survey analysis has helped in exploring several MAC protocols for their compatibility towards mission critical scenarios. In this paper we propose a novel energy efficient contention based ADMC-MAC protocol. This protocol is more adaptable to mission critical applications by improving the data delivery performance based on traffic conditions considering the queue size of the node and also have improved energy efficient performance. This protocol overcomes the lacunas of standard MAC protocols. Two algorithms have been proposed in this protocol. The first algorithm, which is priority based, select the node as cluster head with high number of packets in queue and having maximum energy among the neighboring nodes forming virtual cluster. The second algorithm uses regression technique for deciding the duty cycle of selected node based on traffic conditions and residual energy of the node. Only the selected nodes take part in transmission of packets. So the packets overloading at intermediate nodes is reduced. This helps in increasing the overall efficiency of the system by enhancing energy saving up to 71.452% as compare to S-MAC protocol in mission critical scenarios. The packet delivery ratio is enhanced by 15.198 percent in mission critical scenarios along with considerable improvement in throughput. S-MAC is found to be the most appropriate existing MAC protocol which can be enhanced for mission critical scenarios. So the proposed protocol is enhanced S-MAC protocol implemented in NS-2.35 and the results are compared with standard S-MAC protocol and latest MC-MAC mission critical MAC protocol. It is found that the proposed protocol ADMC-MAC outperforms the latest MC-MAC protocol in terms of energy saving and also provides efficient data delivery performance.

An Enhanced Message Priority Mechanism in IEEE 802.11p Based Vehicular Networks

IEEE 802.11p is a standard MAC protocol for wireless access in vehicular environments (WAVEs). If a packet collision happens when a safety message is sent out, IEEE 802.11p chooses a random back-off counter value in a fixed-size contention window. However, depending on the random choice of back-off counter value, it is still possible that less important messages are sent out first while more important messages are delayed longer until sent out. In this paper, we present a new scheme for safety message scheduling, called the enhanced message priority mechanism (EMPM). It consists of the following two components: the benefit-value algorithm, which calculates the priority of the messages depending on the speed, deceleration, and message lifetime; and the back-off counter selection algorithm, which chooses the non-uniform back-off counter value in order to reduce the collision probability and to enhance the throughput of the highly beneficial messages. Numerical results show that the EMPM can significantly improve the throughput and delay of messages with high benefits when compared with existing MAC protocols. Consequently, the EMPM can provide better QoS support for the more important and urgent messages.

A new joint strategy of radio channel allocation and power control for wireless mesh networks

For wireless mesh networks, it is critical to allocate the limited number of radio channels efficiently while mitigating the co-channel inference to improve network performance. For this reason, after extensively reviewing the related work, we present a new joint radio channel allocation (RCA) and power control (PC) strategy for wireless mesh networks. First, we formulate the RCA problem as a multiple objective optimization problem, with the constraints of transmission power and traffic data rates, while effective channel utilization (ECU) is chosen as the target metric for optimization. Second, we incorporate the channel status into the model of MAC protocols, including as signal-to-noise ratio (SNR) and transmission power. Consequently, the PC is incorporated into the ECU for channel allocation. Third, we propose to directly maximize the ECU to find both optimal radio channel and transmission power. The resulting strategy is a fully distributed RCA/PC algorithm without relying on a coordination mechanism among mesh routers. Our extensive simulation results have demonstrated that the proposed algorithm significantly outperforms the existing RCA strategies and the standard MAC protocols in performance such as throughput, packet dropping, delay and delay jitter.

Transmission power control techniques for wireless sensor networks

Communication is usually the most energy-consuming event in Wireless Sensor Networks (WSNs). One way to significantly reduce energy consumption is applying transmission power control (TPC) techniques to dynamically adjust the transmission power. This article presents two new TPC techniques for WSNs. The experimental evaluation compares the performance of the TCP techniques with B-MAC, the standard MAC protocol of the Mica 2 platform. These experiments take into account different distances among nodes, concurrent transmissions and node mobility. The new transmission power control techniques decrease energy consumption by up to 57% over B-MAC while maintaining the reliability of the channel. Under a low mobility scenario, the proposed protocols delivered up to 95% of the packets, showing that such methods are able to cope with node movement. We also show that the contention caused by higher transmission levels might be lower than analytical models suggest, due to the action of the capture effect.

Improving Quality of Service and Assuring Fairness in WLAN Access Networks

As public deployment of wireless local area networks (WLANs) has increased and various applications with different service requirements have emerged, fairness and quality of service (QoS) are two imperative issues in allocating wireless channels. This study proposes a fair QoS agent (FQA) to simultaneously provide per-class QoS enhancement and per-station fair channel sharing in WLAN access networks. FQA implements two additional components above the 802.11 MAC: a dual service differentiator and a service level manager. The former is intended to improve QoS for different service classes by differentiating service with appropriate scheduling and queue management algorithms, while the latter is to assure fair channel sharing by estimating the fair share for each station and dynamically adjusting the service levels of packets. FQA assures (weighted) fairness among stations in terms of channel access time without decreasing channel utilization. Furthermore, it can provide quantitative service assurance in terms of queuing delay and packet loss rate. FQA neither resorts to any complex fair scheduling algorithm nor requires maintaining per-station queues. Since the FQA algorithm is an add-on scheme above the 802.11 MAC, it does not require any modification of the standard MAC protocol. Extensive ns-2 simulations confirm the effectiveness of the FQA algorithm with respect to the per class QoS enhancement and per-station fair channel sharing

An M-time inheriting transmission strategy for interactive multimedia applications in wireless networks

With the development of IEEE 802.11 WLAN techniques, the wireless network bandwidth has gradually become sufficient for many multimedia applications. However, the standard MAC protocol is originally designed for traditional data transmission fashions, which are asymmetric transmissions, and seems to be not an efficient transmission fashion for recently oncoming multimedia applications. A sort of interactive multimedia applications, such as video conference, interactive Internet game, and network phone (VoIP), etc., is more and more popular in the world. The features of these interactive applications are frequent and bi-directional data exchange, which will cause large and unnecessary transmission overheads for channel contention under the standard MAC protocol. To reduce these overheads and improve system transmission efficiency, an M-time inheriting transmission strategy (MITS) is proposed in this paper. The MITS is a dynamically bi-directional transmission strategy, which uses the token-like fashion to allow the receiver to send its data frame immediately without participating in following channel contention. Simulation results show that the MITS can indeed improve system goodput of the standard MAC protocol in the environments with interactive applications.

Autonomous Power Control MAC Protocol for Mobile Ad Hoc Networks

Battery energy limitation has become a performance bottleneck for mobile ad hoc networks. IEEE 802.11 has been adopted as the current standard MAC protocol for ad hoc networks. However, it was developed without considering energy efficiency. To solve this problem, many modifications on IEEE 802.11 to incorporate power control have been proposed in the literature. The main idea of these power control schemes is to use a maximum possible power level for transmitting RTS/CTS and the lowest acceptable power for sending DATA/ACK. However, these schemes may degrade network throughput and reduce the overall energy efficiency of the network. This paper proposes autonomous power control MAC protocol (APCMP), which allows mobile nodes dynamically adjusting power level for transmitting DATA/ACK according to the distances between the transmitter and its neighbors. In addition, the power level for transmitting RTS/CTS is also adjustable according to the power level for DATA/ACK packets. In this paper, the performance of APCMP protocol is evaluated by simulation and is compared with that of other protocols.

Performance analysis of BusNet protocol for backplane bus-based interprocessor communication

Nowadays, backplane bus-based multiprocessor systems often utilize the standard network protocol such as TCP/IP for communication between processors on the backplane bus. In such systems, it is common for the backplane bus to emulate the standard MAC protocols such as CSMA/CD. This paper aims to analyze the delay performance of the MAC emulation-based backplane network by constructing queueing models based on detailed bus operations. For this purpose, we choose BusNet as a target protocol. BusNet is an ANSI standard network protocol and its specification contains basic operations commonly used in most backplane buses. We investigate the throughput-delay characteristics in terms of packet size, block transfer scale, and arbitration scheme. We also compare the packet delay in BusNet with the IEEE 802.3 CSMA/CD network which BusNet is expected to be compatible with. The simulation result shows how an optimal block transfer scale can be determined in respect of the performance trade-off between BusNet and other real-time traffics.