Trickle Timer Research Articles

Adaptive and Fair Route Update Algorithm for Low Power and Lossy Networks in the Internet of Things

Internet of Things (IoT) refers to the network of physical objects embedded with sensors, software, and other technologies for the purpose of exchanging data with other devices over the internet. One of the routing protocols accredited to the IoT applications in Low Power and Lossy Networks is the Routing Protocol for Low Power and Lossy Networks (RPL). Trickle timer algorithm is considered one of the major algorithms in the RPL used to control the flow of control messages through the network. Performance evaluation has shown that the trickle algorithm is suffering from load balancing problems. In this study, an adaptive algorithm, called the Fair-K algorithm, is introduced for maintaining routing information in Low Power and Lossy Networks. It differs from the standard Trickle in two ways. First, the Fair-K algorithm provides an elastic selection of redundancy value based on the node degree in the network. Second, it provides a new scheme in order to solve the bottleneck problem in the network. The performance evaluation of the Fair-K algorithm is validated using extensive simulation experiments. The results indicate that the Fair-K algorithm reduces the convergence time by 80%, power consumption by 20%, and the total delay by 78% while maintaining approximately the same packet delivery ratios.

A Comprehensive Survey on RPL: Evolution and Challenges

LLNs (Low Power and Lossy Networks) are becoming hot research topics due to challenges posed by their limited battery life, computing power, memory and transmission power. LLNs require a routing protocol which can perform efficiently with their limitations. IETF has come up with RPL as standard routing protocol for LLNs. It builds energy efficient network. But it also has major limitations and several research have happened to overcome the same. This paper is survey of RPL challenges and recent research on RPL extensions. Major RPL limitations include packet loss under noisy scenario, increased DODAG depth causing high energy consumption. TTA (Trickle Timer Algorithm) is important part of RPL. It is used to manage control messages flow. Limitation of trickle algorithm results in problem of short time for listening and it can make few nodes crave for delay and higher latency. E-Trickle is proposed to overcome the listen only period, improve convergence time and energy consumption. QOI (Quality of Information) aware RPL reduces the energy consumption with less data transmission. RPL operates under one sink. Entire data flows towards the single sink. RPL doesn’t specify when, where and how more number of sinks need to be used. Dynamic rescue sink is RPL enhancement built with real timetracking of nodes’ performance in RPL networks to propose new sinks when required. AMI (Advanced metering infrastructure) is one of the application in smart grid for connecting smart metering devices at homes. It is critical to have efficient routing protocol for AMI as the smart meter nodes are resource constrained. AMI with high density networks suffer from high packet loss, network congestion retransmissions, increased latency, control traffic overhead and power consumption. LQE (Link Quality Estimation) influences quality of selected route and energy consumption. RL-probe measures link quality precisely with small overhead and energy consumption. RL-probe reduces packet loss by reacting to link quality variations and link failures due to mobility. Communication overhead needs to be as minimal as possible inLLNs with limited resources. Adaptive timing model uses dynamic method to decide frequency of executing objective function to construct DODAG based on degree of surrounding changes and reduces the control messages overhead. Objective is to bring down the PLR (packet loss ratio), overhead of control messages and battery usage. RPL doesn’t give good results for high throughput and changes in network conditions. This prevents use of RPL in high speed sensors and mobile sensing applications. BRPL is extension to RPL which combines RPL objective function (OF) with back pressure routing to handle dynamic traffic load and mobility.

Mobility-Aware Energy-Efficient Parent Selection Algorithm for Low Power and Lossy Networks

IPv6 routing protocol for low-power and lossy networks (RPL) is a standardized routing protocol for the energy-constrained networks in the Internet of Things networks. Nowadays, many real-time applications demand mobility support among the nodes in RPL with a wide range of speed. But, supporting mobility in RPL becomes a critically challenging issue because the devices are resource constrained and the communication links are lossy to establish a stable network. Moreover, control packet overhead increases rapidly over mobility, which in turn drains out energy and affects the overall lifetime of the network. In this paper, we propose a mobility-aware energy efficient parent selection algorithm that supports random mobility of the nodes in RPL and chooses the best parent from the preferred parent list based on the metrics, namely, expected transmission count, expected lifetime, received signal strength indicator, and Euclidean distance ( ${d} _{ij}$ ) between the mobile node and the parent node under selection. We also propose a dynamic trickle algorithm for Trickle Timer to solve long listen only period and allocates timer dynamically based on the random set of neighbor nodes under mobility. Specifically, this paper analyzes the performance of the proposed algorithm against previous algorithms, namely, original RPL, corona-RPL, enhanced trickle, reverse Trickle Timer mechanism, and mobility-enhanced RPL in terms of packet delivery ratio, energy consumption, and average end-to-end delay under different scenarios.

A new scheme for RPL to handle mobility in wireless sensor networks

Mobile wireless sensor networks (WSNs) are characterised by dynamic changes in the network topology leading to route breaks and disconnections. The IPv6 routing protocol for low power and lossy networks (RPL), which has become a standard, uses the Trickle timer algorithm to handle changes in the network topology. However, neither RPL nor Trickle timer are well adapted to mobility. This paper investigates the problem of supporting mobility when using RPL. It enhances RPL to fit with sensors' mobility by studying two cases. Firstly, it proposes to modify RPL in order to fit with a dynamic and hybrid topology in the context of medical applications. Secondly, it investigates a more general case and introduces a new adaptive timer for RPL. The proposed approach is validated through extensive simulations and compared with existing protocols in the literature. Results show that our proposal significantly reduces disconnections and increases packet delivery ratio while maintaining low overhead.

A Joining Procedure and Synchronization for TSCH-RPL Wireless Sensor Networks.

Wireless Sensor Networks have become a key enabler for Industrial Internet of Things (IoT) applications; however, to adapt to the derived robust communication requirements, deterministic and scheduled medium access should be used, along with other features, such as channel hopping and frequency diversity. Implementing these mechanisms requires a correct synchronization of all devices in the network, a stage in deployment that can lead to non-operational networks. The present article presents an analysis of such situations and possible solutions, including the common current approaches and recommendations, and proposes a new beacon advertising method based on a specific Trickle Timer for the Medium Access Control (MAC) Time-Slotted Channel Hopping (TSCH) layer, decoupling from the timers in the network and routing layers. With this solution, improvements in connection success, time to join, and energy consumption can be obtained for the widely extended IEEE802.15.4e standard.

An Efficient and Energy-saving Data Dissemination Mechanism for Low-power and Lossy Networks

A low-power and lossy network (LLN) connects a huge amount of resource-constrained devices. These devices are limited in processing ability, memory, and power supply. With a view to performance, the Trickle timer algorithm was proposed to reduce control overhead of the routing protocol for LLNs, which aims to emphasize a high data transfer rate while consuming low power. In this paper, we propose an efficient and energy-saving data dissemination mechanism for LLNs to overcome the choke-point problem left over by the Trickle timer mechanism. A new parameter is introduced to indicate the neighbor density, and two modes are utilized to distinguish a node’s actions in silence or burst situations. If a node is detected inside a circle of updated nodes, it will enter silence mode to reduce broadcasting frequency. When a node is recognized on the border, it will enter burst mode to increase broadcasting frequency. Simulation results validate that our method outperforms the Trickle timer mechanism in terms of convergence time and energy consumption to disseminate data, especially in a dense LLN.

Improved Trickle Algorithm for Routing Protocol for Low Power and Lossy Networks

Routing protocol for low power and lossy networks (RPL) is designed in order to avoid the routing issues in wireless sensor networks due to limited energy of nodes, link failures, and so on. RPL constructs the destination oriented directed acyclic graph (DODAG) out of the physical network by using various constraints, such as different routing metrics, objective functions, and so on. The trickle timer in RPL is used to reduce the control traffic overhead by dividing the time into intervals. It increases its sending rate of the control messages if an inconsistency is detected to resolve it quickly otherwise it decreases its sending rate by exponentially increasing its window size. The trickle-F algorithm solves the load balancing problem by implementing the fair broadcast suppression mechanism. Our proposed improved-trickle algorithm sets the redundancy counter to zero not at the beginning of new interval but at the time of suppression or transmission of the DODAG information object message in the trickle-F algorithm to solve the load balancing problem and to reduce the energy and power consumption by taking into consideration the messages heard from time t to the end of the interval.

A new elastic trickle timer algorithm for Internet of Things

The term IoT emerging services is used to refer to the modern kinds of services that IoT can provide to enhance service and experience quality by reducing complexity, speeding up requests, and using techniques involved with cloud, Big Data, and protocols to allows services to function seamlessly. Therefore, IoT utilises protocols found within different network layers. RPL or Routing Protocol for Low Power and Lossy Networks is one of the most important routing protocols utilised on the network layer. This protocol is considered an IPV6 distance vector proactive routing protocol. The trickle timer algorithm is one of its major components. This algorithm is used to control and track the control messages’ flow throughout the network. However, one weakness of the trickle algorithm is that it suffers from short listen problem that makes some nodes starve for delay and long latency in propagating transmissions. Based on existing literature, there have been several research studies on this trickle method. Development of the Enhanced Trickle algorithm (E-Trickle) was done to get rid of the listen only period. However, there still is relatively low activity on studying the trickle algorithm’s performance merits. Our proposed elastic trickle timer algorithm will try to fill this gap by dealing only with the listen to only period problems. The power consumption and convergence time are mainly affected. Therefore, our proposed algorithm was incorporated in the Routing Protocol for Low Power and Lossy Networks (RPL). Different network densities were used to evaluate the simulation experiments. Its implementation was done on 20, 40, 60, and 80 nodes using different ratios for reception success (RX) (20%, 40%, 60%, 80%, and 100%), and grid network and random topologies were used. The Cooja 2.7 simulator was used to implement the simulation experiments, and RPL performance was studied through the elastic trickle timer algorithm. Measurement of the simulation experiments was done on various performance metrics such as packet delivery ratio (PDR), convergence time, and power consumption. Comparison of the results was done using the standard trickle timer algorithm. Using random and grid topologies, the results revealed greater enhancements in terms of convergence time. Simulation results revealed that when the network was made up of 20 nodes, there was 35% less convergence time. Moreover, when 40 nodes were randomly placed, there was 62% less convergence time, and 71% less convergence time when 40 nodes were situated in a grid topology. Additionally, there was 70% less convergence time when the network was made up of 60 nodes and approximately 76% less convergence time when there were 80 nodes. Moreover, the simulation results revealed that in terms of energy consumption, the new algorithm exhibited superior performance characteristics.

A new Scheme for RPL to handle Mobility in Wireless Sensor Networks

Mobile wireless sensor networks (WSNs) are characterised by dynamic changes in the network topology leading to route breaks and disconnections. The IPv6 routing protocol for low power and lossy networks (RPL), which has become a standard, uses the Trickle timer algorithm to handle changes in the network topology. However, neither RPL nor Trickle timer are well adapted to mobility. This paper investigates the problem of supporting mobility when using RPL. It enhances RPL to fit with sensors' mobility by studying two cases. Firstly, it proposes to modify RPL in order to fit with a dynamic and hybrid topology in the context of medical applications. Secondly, it investigates a more general case and introduces a new adaptive timer for RPL. The proposed approach is validated through extensive simulations and compared with existing protocols in the literature. Results show that our proposal significantly reduces disconnections and increases packet delivery ratio while maintaining low overhead.

A Proactive Trickle-based Mechanism for Discovering CoRE Resource Directories

The CoRE working group at the IETF has proposed a Resource Directory (RD) solution to facilitate the discovery of the resources provided by constrained wireless sensor and actuator networks. For such a mechanism to be effectively deployable, nodes must first discover the existence of an RD in the network before being able to exploit its functionalities. This paper presents Proactive RD Discovery (PRD); a scalable, reliable, and effective mechanism to discover an RD. To achieve such qualities, the proposed mechanism deploys adaptive Trickle timers. PRD is implemented in Contiki OS and evaluated using emulated sensor/actuator nodes in the Cooja simulator. Simulation results show important performance enhancements in terms of energy consumption, generated traffic, RD discovery time, and reliability when compared with the default discovery mechanism bundled with the RD.