Towards Improving TSCH Energy Efficiency: An Analytical Approach to a Practical Implementation

The IEEE 802.15.4-2015 standard defines a number of Medium Access Control (MAC) layer protocols for low power wireless communications, which are desirable for energy-constrained Internet of Things (IoT) devices. Originally defined in the IEEE 802.15.4e amendment, the Time Slotted Channel Hopping (TSCH) has recently been attracting attention from the research community due to its reduced contention (time scheduling) and robustness against fading (channel hopping). However, it requires a certain level of synchronization between the nodes, which can increase the energy consumption. In this work, we implement the Guard Beacon (GB) strategy, aiming at reducing the guard time usually implemented to compensate for imperfect synchronization. Moreover, besides presenting a realistic energy consumption model for a Contiki Operating System-based TSCH network, we show through analytical and practical results that, without the proposed scheme, the power consumption can be more than 13% higher.

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Body Sensors and Healthcare Monitoring

Advances in Healthcare Information Systems and Administration - Telemedicine and E-Health Services, Policies, and Applications ◽

10.4018/978-1-4666-0888-7.ch002 ◽

2012 ◽

pp. 26-55

Author(s):

Begonya Otal ◽

Luis Alonso ◽

Christos V. Verikoukis

Keyword(s):

Energy Consumption ◽

Sensor Networks ◽

Ieee 802.15.4 ◽

Body Sensor Networks ◽

Mac Layer ◽

Medical Systems ◽

Battery Lifetime ◽

Body Sensors ◽

Healthcare Monitoring

The aging population and the high expectations towards quality of life in our society lead to the need of more efficient and affordable medical systems and monitoring solutions. The development of wireless Body Sensor Networks (BSNs) offers a platform to establish such a healthcare monitoring systems. However, BSNs in the healthcare domain operate under conflicting requirements. These are the maintenance of the desired reliability and message latency of data transmissions (i.e. quality of service), while simultaneously maximizing battery lifetime of individual body sensors. In doing so, the characteristics of the entire system, especially the Medium Access Control (MAC) layer, have to be considered. For this reason, this chapter aims for the optimization of the MAC layer by using energy-saving techniques for BSNs. The fact that the IEEE 802.15.4 MAC does not fully satisfy BSNs requirements highlights the need for the design of new scalable MAC solutions, which guarantee low-power consumption to the maximum number of body sensors in high density areas (i.e., in saturation conditions). In order to emphasize IEEE 802.15.4 MAC limitations, this chapter presents a detailed overview of this de facto standard for Wireless Sensor Networks (WSNs), which serves as a link for the introduction and description of the here proposed Distributed Queuing (DQ) MAC protocol for BSN scenarios. Within this framework, an extensive DQ MAC energy-consumption analysis in saturation conditions is presented to be able to evaluate its performance in relation to IEEE 802.5.4 MAC in highly dense BSNs. The obtained results show that the proposed scheme outperforms IEEE 802.15.4 MAC in average energy consumption per information bit, thus providing a better overall performance that scales appropriately to BSNs under high traffic conditions. These benefits are obtained by eliminating back-off periods and collisions in data packet transmissions, while minimizing the control overhead.

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Collision-Free Advertisement Scheduling for IEEE 802.15.4-TSCH Networks

Sensors ◽

10.3390/s19081789 ◽

2019 ◽

Vol 19 (8) ◽

pp. 1789 ◽

Cited By ~ 7

Author(s):

Apostolos Karalis ◽

Dimitrios Zorbas ◽

Christos Douligeris

Keyword(s):

Power Consumption ◽

Ieee 802.15.4 ◽

Mac Protocol ◽

High Reliability ◽

Mobile Nodes ◽

Medium Access ◽

Worst Case ◽

Channel Hopping ◽

Transmission Schedule ◽

Scheduling Method

IEEE802.15.4-time slotted channel hopping (TSCH) is a medium access control (MAC) protocol designed to support wireless device networking, offering high reliability and low power consumption, two features that are desirable in the industrial internet of things (IIoT). The formation of an IEEE802.15.4-TSCH network relies on the periodic transmissions of network advertising frames called enhanced beacons (EB). The scheduling of EB transmissions plays a crucial role both in the joining time and in the power consumption of the nodes. The existence of collisions between EB is an important factor that negatively affects the performance. In the worst case, all the neighboring EB transmissions of a node may collide, a phenomenon which we call a full collision. Most of the EB scheduling methods that have been proposed in the literature are fully or partially based on randomness in order to create the EB transmission schedule. In this paper, we initially show that the randomness can lead to a considerable probability of collisions, and, especially, of full collisions. Subsequently, we propose a novel autonomous EB scheduling method that eliminates collisions using a simple technique that does not increase the power consumption. To the best of our knowledge, our proposed method is the first non-centralized EB scheduling method that fully eliminates collisions, and this is guaranteed even if there are mobile nodes. To evaluate our method, we compare our proposal with recent and state-of-the-art non-centralized network-advertisement scheduling methods. Our evaluation does not consider only fixed topology networks, but also networks with mobile nodes, a scenario which has not been examined before. The results of our simulations demonstrate the superiority of our method in terms of joining time and energy consumption.

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Energy Analysis of Contention Tree-Based Access Protocols in Dense Machine-to-Machine Area Networks

Journal of Sensors ◽

10.1155/2015/685164 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Francisco Vázquez-Gallego ◽

Luis Alonso ◽

Jesus Alonso-Zarate

Keyword(s):

Ieee 802.15.4 ◽

Theoretical Models ◽

Energy Performance ◽

High Energy ◽

Area Network ◽

Medium Access ◽

Splitting Algorithm ◽

Machine To Machine ◽

Computer Based ◽

Energy Constrained

Machine-to-Machine (M2M) area networks aim at connecting an M2M gateway with a large number of energy-constrained devices that must operate autonomously for years. Therefore, attaining high energy efficiency is essential in the deployment of M2M networks. In this paper, we consider a dense M2M area network composed of hundreds or thousands of devices that periodically transmit data upon request from a gateway or coordinator. We theoretically analyse the devices’ energy consumption using two Medium Access Control (MAC) protocols which are based on a tree-splitting algorithm to resolve collisions among devices: the Contention Tree Algorithm (CTA) and the Distributed Queuing (DQ) access. We have carried out computer-based simulations to validate the accuracy of the theoretical models and to compare the energy performance using DQ, CTA, and Frame Slotted-ALOHA (FSA) in M2M area networks with devices in compliance with the IEEE 802.15.4 physical layer. Results show that the performance of DQ is totally independent of the number of contending devices, and it can reduce the energy consumed per device in more than 35% with respect to CTA and in more than 80% with respect to FSA.

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Contiki-Based IEEE 802.15.4 Channel Capacity Estimation and Suitability of Its CSMA-CA MAC Layer Protocol for Real-Time Multimedia Applications

Mobile Information Systems ◽

10.1155/2015/398637 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Muhammad Omer Farooq ◽

Thomas Kunz

Keyword(s):

Real Time ◽

Channel Capacity ◽

Packet Loss ◽

Ieee 802.15.4 ◽

Mac Protocol ◽

Multimedia Applications ◽

Mac Layer ◽

Medium Access ◽

Available Bandwidth ◽

Bandwidth Guarantees

Real-time multimedia applications require quality of service (QoS) provisioning in terms of bounds on delay and packet loss along with soft bandwidth guarantees. The shared nature of the wireless communication medium results in interference. Interference combined with the overheads, associated with a medium access control (MAC) protocol, and the implementation of a networking protocol stack limit the available bandwidth in IEEE 802.15.4-based networks and can result in congestion, even if the transmission rates of nodes are well below the maximum bandwidth supported by an underlying communication technology. Congestion degrades the performance of admitted real-time multimedia flow(s). Therefore, in this paper, we experimentally derive the IEEE 802.15.4 channel capacity using an unslotted CSMA-CA MAC protocol. We experimentally derive channel capacity for two cases, that is, when the CSMA-CA protocol is working without ACKs and when it is working with ACKs. Moreover, for both cases, we plot the relationship of offered data load with delay and packet loss rate. Simulation results demonstrate that the parameters that affect the choice of a CSMA-CA MAC layer protocol are end-to-end delay and packet loss requirements of a real-time multimedia flow, data load within the interference range of transmitters along the forwarding path, and length of the forwarding path.

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Time Slotted Channel Hopping and ContikiMAC for IPv6 Multicast-Enabled Wireless Sensor Networks

Sensors ◽

10.3390/s21051771 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1771

Author(s):

Eden Teshome ◽

Diana Deac ◽

Steffen Thielemans ◽

Matthias Carlier ◽

Kris Steenhaut ◽

...

Keyword(s):

Energy Consumption ◽

High Energy ◽

Wireless Sensor ◽

Delivery Ratio ◽

Lossy Networks ◽

Medium Access ◽

Channel Hopping ◽

Multicast Forwarding ◽

High Energy Consumption

Smart buildings benefit from IEEE 802.15.4e time slotted channel hopping (TSCH) medium access for creating reliable and power aware wireless sensor and actuator networks (WSANs). As in these networks, sensors are supposed to communicate to each other and with actuators, IPv6 multicast forwarding is seen as a valuable means to reduce traffic. A promising approach to multicast, based on the Routing Protocol for Low Power and Lossy Networks (RPL) is Bidirectional Multicast RPL Forwarding (BMRF). This paper aimed to analyze the performance of BMRF over TSCH. The authors investigated how an adequate TSCH scheduler can help to achieve a requested quality of service (QoS). A theoretical model for the delay and energy consumption of BMRF over TSCH is presented. Next, BMRF’s link layer (LL) unicast and LL broadcast forwarding modes were analyzed on restricted and realistic topologies. On topologies with increased interference, BMRF’s LL broadcast on top of TSCH causes high energy consumption, mainly because of the amount of energy needed to run the schedule, but it significantly improves packet delivery ratio and delay compared to ContikiMAC under the same conditions. In most cases, the LL unicast was found to outperform the LL broadcast, but the latter can be beneficial to certain applications, especially those sensitive to delays.

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A Comprehensive Review on Energy Harvesting Integration in IoT Systems from MAC Layer Perspective: Challenges and Opportunities

Sensors ◽

10.3390/s21093097 ◽

2021 ◽

Vol 21 (9) ◽

pp. 3097

Author(s):

Golshan Famitafreshi ◽

M. Shahwaiz Afaqui ◽

Joan Melià-Seguí

Keyword(s):

Energy Consumption ◽

Energy Harvesting ◽

Energy Requirements ◽

Mac Layer ◽

Unified Framework ◽

Essential Information ◽

Survey Paper ◽

Hybrid Approaches ◽

Smart Healthcare ◽

Iot Devices

The Internet of Things (IoT) is revolutionizing technology in a wide variety of areas, from smart healthcare to smart transportation. Due to the increasing trend in the number of IoT devices and their different levels of energy requirements, one of the significant concerns in IoT implementations is powering up the IoT devices with conventional limited lifetime batteries. One efficient solution to prolong the lifespan of these implementations is to integrate energy harvesting technologies into IoT systems. However, due to the characteristics of the energy harvesting technologies and the different energy requirements of the IoT systems, this integration is a challenging issue. Since Medium Access Control (MAC) layer operations are the most energy-consuming processes in wireless communications, they have undergone different modifications and enhancements in the literature to address this issue. Despite the essential role of the MAC layer to efficiently optimize the energy consumption in IoT systems, there is a gap in the literature to systematically understand the possible MAC layer improvements allowing energy harvesting integration. In this survey paper, we provide a unified framework for different wireless technologies to measure their energy consumption from a MAC operation-based perspective, returning the essential information to select the suitable energy harvesters for different communication technologies within IoT systems. Our analyses show that only 23% of the presented protocols in the literature fulfill Energy Neutral Operation (ENO) condition. Moreover, 48% of them are based on the hybrid approaches, which shows its capability to be adapted to energy harvesting. We expect this survey paper to lead researchers in academia and industry to understand the current state-of-the-art of energy harvesting MAC protocols for IoT and improve the early adoption of these protocols in IoT systems.

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TSCH Evaluation under Heterogeneous Mobile Scenarios

IoT ◽

10.3390/iot2040033 ◽

2021 ◽

Vol 2 (4) ◽

pp. 656-668

Author(s):

Charalampos Orfanidis ◽

Atis Elsts ◽

Paul Pop ◽

Xenofon Fafoutis

Keyword(s):

Mobile Applications ◽

Ieee 802.15.4 ◽

Autonomous Robots ◽

Industrial Applications ◽

Mobility Patterns ◽

Medium Access ◽

Access Protocol ◽

Channel Hopping ◽

High Flexibility ◽

Ieee 802.15.4 Standard

Time Slotted Channel Hopping (TSCH) is a medium access protocol defined in the IEEE 802.15.4 standard. It has proven to be one of the most reliable options when it comes to industrial applications. TSCH offers a degree of high flexibility and can be tailored to the requirements of specific applications. Several performance aspects of TSCH have been investigated so far, such as the energy consumption, reliability, scalability and many more. However, mobility in TSCH networks remains an aspect that has not been thoroughly explored. In this paper, we examine how TSCH performs under mobility situations. We define two mobile scenarios: one where autonomous agriculture vehicles move on a predefined trail, and a warehouse logistics scenario, where autonomous robots/vehicles and workers move randomly. We examine how different TSCH scheduling approaches perform on these mobility patterns and when a different number of nodes are operating. The results show that the current TSCH scheduling approaches are not able to handle mobile scenarios efficiently. Moreover, the results provide insights on how TSCH scheduling can be improved for mobile applications.

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MAC Layer Protocols for Internet of Things: A Survey

Future Internet ◽

10.3390/fi11010016 ◽

2019 ◽

Vol 11 (1) ◽

pp. 16 ◽

Cited By ~ 25

Author(s):

Luiz Oliveira ◽

Joel Rodrigues ◽

Sergei Kozlov ◽

Ricardo Rabêlo ◽

Victor Albuquerque

Keyword(s):

Internet Of Things ◽

Access Control ◽

Medium Access Control ◽

Long Range ◽

Radio Frequency Identification ◽

Ieee 802.15.4 ◽

Mac Layer ◽

Medium Access ◽

Long Distance ◽

Research Issues

Due to the wide variety of uses and the diversity of features required to meet an application, Internet of Things (IoT) technologies are moving forward at a strong pace to meet this demand while at the same time trying to meet the time-to-market of these applications. The characteristics required by applications, such as coverage area, scalability, transmission data rate, and applicability, refer to the Physical and Medium Access Control (MAC) layer designs of protocols. This paper presents a deep study of medium access control (MAC) layer protocols that are used in IoT with a detailed description of such protocols grouped (by short and long distance coverage). For short range coverage protocols, the following are considered: Radio Frequency Identification (RFID), Near Field Communication (NFC), Bluetooth IEEE 802.15.1, Bluetooth Low Energy, IEEE 802.15.4, Wireless Highway Addressable Remote Transducer Protocol (Wireless-HART), Z-Wave, Weightless, and IEEE 802.11 a/b/g/n/ah. For the long range group, Narrow Band IoT (NB-IoT), Long Term Evolution (LTE) CAT-0, LTE CAT-M, LTE CAT-N, Long Range Protocol (LoRa), and SigFox protocols are studied. A comparative study is performed for each group of protocols in order to provide insights and a reference study for IoT applications, considering their characteristics, limitations, and behavior. Open research issues on the topic are also identified.

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Intra-Network Interference Robustness: An Empirical Evaluation of IEEE 802.15.4-2015 SUN-OFDM

Electronics ◽

10.3390/electronics9101691 ◽

2020 ◽

Vol 9 (10) ◽

pp. 1691

Author(s):

Robbe Elsas ◽

Jeroen Hoebeke ◽

Dries Van Leemput ◽

Adnan Shahid ◽

Glenn Daneels ◽

...

Keyword(s):

Orthogonal Frequency Division Multiplexing ◽

Ieee 802.15.4 ◽

Empirical Evaluation ◽

Medium Access ◽

Frequency Space ◽

Time Frequency ◽

Channel Hopping ◽

Access Mode ◽

Utility Network ◽

Modulation Diversity

While IEEE 802.15.4 and its Time Slotted Channel Hopping (TSCH) medium access mode were developed as a wireless substitute for reliable process monitoring in industrial environments, most deployments use a single/static physical layer (PHY) configuration. Instead of limiting all links to the throughput and reliability of a single Modulation and Coding Scheme (MCS), you can dynamically re-configure the PHY of link endpoints according to the context. However, such modulation diversity causes links to coincide in time/frequency space, resulting in poor reliability if left unchecked. Nonetheless, to some level, intentional spatial overlap improves resource efficiency while partially preserving the benefits of modulation diversity. Hence, we measured the mutual interference robustness of certain Smart Utility Network (SUN) Orthogonal Frequency Division Multiplexing (OFDM) configurations, as a first step towards combining spatial re-use and modulation diversity. This paper discusses the packet reception performance of those PHY configurations in terms of Signal to Interference Ratio (SIR) and time-overlap percentage between interference and targeted parts of useful transmissions. In summary, we found SUN-OFDM O3 MCS1 and O4 MCS2 performed best. Consequently, one should consider them when developing TSCH scheduling mechanisms in the search for resource efficient ubiquitous connectivity through modulation diversity and spatial re-use.

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MAC protocol with grouping awareness GMAC for large scale Internet-of-Things network

PeerJ Computer Science ◽

10.7717/peerj-cs.733 ◽

2021 ◽

Vol 7 ◽

pp. e733

Author(s):

Abdulrahman Sameer Sadeq ◽

Rosilah Hassan ◽

Azana Hafizah Mohd Aman ◽

Hasimi Sallehudin ◽

Khalid Allehaibi ◽

...

Keyword(s):

Energy Consumption ◽

Internet Of Things ◽

Large Scale ◽

Ieee 802.15.4 ◽

Mac Protocol ◽

Cluster Head ◽

Delivery Ratio ◽

Energy Aware ◽

Medium Access ◽

Two Stages

The development of Medium Access Control (MAC) protocols for Internet of Things should consider various aspects such as energy saving, scalability for a wide number of nodes, and grouping awareness. Although numerous protocols consider these aspects in the limited view of handling the medium access, the proposed Grouping MAC (GMAC) exploits prior knowledge of geographic node distribution in the environment and their priority levels. Such awareness enables GMAC to significantly reduce the number of collisions and prolong the network lifetime. GMAC is developed on the basis of five cycles that manage data transmission between sensors and cluster head and between cluster head and sink. These two stages of communication increase the efficiency of energy consumption for transmitting packets. In addition, GMAC contains slot decomposition and assignment based on node priority, and, therefore, is a grouping-aware protocol. Compared with standard benchmarks IEEE 802.15.4 and industrial automation standard 100.11a and user-defined grouping, GMAC protocols generate a Packet Delivery Ratio (PDR) higher than 90%, whereas the PDR of benchmark is as low as 75% in some scenarios and 30% in others. In addition, the GMAC accomplishes lower end-to-end (e2e) delay than the least e2e delay of IEEE with a difference of 3 s. Regarding energy consumption, the consumed energy is 28.1 W/h for GMAC-IEEE Energy Aware (EA) and GMAC-IEEE, which is less than that for IEEE 802.15.4 (578 W/h) in certain scenarios.

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