Brief announcement: Game theoretical approach for energy-delay balancing in distributed duty-cycled MAC protocols of wireless networks

Optimizing energy consumption and end-to-end (e2e) packet delay in energy constrained distributed wireless networks is a conflicting multi-objective optimization problem. This paper investigates this trade-off from a game-theoretic perspective, where the two optimization objectives are considered as virtual game players that attempt to optimize their utility values. The cost model of each player is mapped through a generalized optimization framework onto protocol specific MAC parameters. A cooperative game is then defined, in which the Nash Bargaining solution assures the balance between energy consumption and e2e packet delay. For illustration, this formulation is applied to three state-of-the-art wireless sensor network MAC protocols; X-MAC, DMAC, and LMAC as representatives of preamble sampling, slotted contention-based, and frame-based MAC categories, respectively. The paper shows the effectiveness of such framework in optimizing protocol parameters for achieving a fair energy-delay performance trade-off, under the application requirements in terms of initial energy budget and maximum e2e packet delay. The proposed framework is scalable with the increase in the number of nodes, as the players represent the optimization metrics instead of nodes.Postprint (author’s final draft

A novel real-time MAC layer protocol for wireless sensor network applications

This paper presents a comparative study of existing real-time MAC layer protocols for wireless sensor networks. Then, a new real-Time MAC protocol is presented that is based on a general purpose MAC protocol, called S-MAC. While medium access strategy in S-MAC is based on contention and back-off schemes, protocol proposed in this paper uses feedback approach as a medium access strategy. As a result of this, it increases consistency in data transmission pattern, which enables it to guarantee end-to-end delay deadlines for soft realtime applications. Proposed protocol works in continuous ON mode of operation at MAC layer and is intended to be used for randomly deployed single stream wireless sensor applications. Finally, a comparative performance analysis of proposed realtime protocol is done with other real-time and general purpose MAC protocols for wireless sensor networks

A Time Tree Medium Access Control for Energy Efficiency and Collision Avoidance in Wireless Sensor Networks

This paper presents a medium access control and scheduling scheme for wireless sensor networks. It uses time trees for sending data from the sensor node to the base station. For an energy efficient operation of the sensor networks in a distributed manner, time trees are built in order to reduce the collision probability and to minimize the total energy required to send data to the base station. A time tree is a data gathering tree where the base station is the root and each sensor node is either a relaying or a leaf node of the tree. Each tree operates in a different time schedule with possibly different activation rates. Through the simulation, the proposed scheme that uses time trees shows better characteristics toward burst traffic than the previous energy and data arrival rate scheme

A survey of adaptive services to cope with dynamics in wireless self-organizing networks

In this article, we consider different types of wireless networks that benefit from and, in certain cases, require self-organization. Taking mobile ad hoc, wireless sensor, wireless mesh, and delay-tolerant networks as examples of wireless self-organizing networks (WSONs), we identify that the common challenges these networks face are mainly due to lack of centralized management, device heterogeneity, unreliable wireless communication, mobility, resource constraints, or the need to support different traffic types. In this context, we survey several adaptive services proposed to handle these challenges. In particular, we group the adaptive services as core services and network-level services. By categorizing different types of services that handle adaptation and the types of adaptations, we intend to provide useful design guidelines for achieving self-organizing behavior in network protocols. Finally, we discuss open research problems to encourage the design of novel protocols for WSONs.</jats:p

Energy-efficient Data Aggregation in Wireless Sensor Networks Using Probabilistic Sleep Scheduling and Compressed Sensing

Each node in a wireless sensor network (WSN) is an inexpensive and small device with a limited source of energy. In many applications related to monitoring of physical phenomenon and natural signals, there is spatio-temporal correlation among the readings from different sensors and different times. This work takes advantage of the correlation and integrates compressed sensing and sleep scheduling to significantly reduce the energy consumption of data aggregation in WSNs. The proposed method is based on probabilistic models, allowing it to be simple, fast, flexible, reliable, and suitable for randomly deployed networks with no defined topology, known location, or time synchronization.Electrical Engineerin

Feedback based real-time MAC (RT-MAC) protocol for data packet streaming in wireless sensor networks

Wireless sensor networks (WSNs) are generally used for event driven monitoring or periodic reporting. Once a triggering event happens, it needs to be reported in real-time as a continuous stream for some duration. In order to address such communication requirements, this thesis introduces a soft Real-Time MAC (RT-MAC) protocol for real-time data packet streaming in wireless sensor networks. RT-MAC eliminates contention for a wireless medium by introducing a feedback control packet, called Clear Channel (CC). As a result, RT-MAC has a consistent and predictable data transmission pattern that provides end-to-end delay guarantees. Additionally, RT-MAC has a lower end-to-end delay than other real-time WSN MAC protocols for two reasons: (1) it maximizes spatial channel reuse by avoiding the false blocking problem caused by request-to-send (RTS) and clear-to-send (CTS) exchanges in wireless MAC protocols (2) it reduces contention duration of control packets to facilitate faster data packet transfer. Thus, RT-MAC facilitates periodic data packet deliveries as well as alarming event reporting. RT-MAC operates both with and without duty cycle mode (sleep/wakeup schedule for sensor nodes). Duty cycle mode of RT-MAC is useful in situations where energy conservation is one of the goals along with real-time requirements. RT-MAC is well suited for multi-hop communication with a large number of hops. RT-MAC protocol supports single-stream communication between a randomly selected source and sink node pair as well as multi-stream communication among different source and sink node pairs. This thesis provides the lower and upper end-to-end delay bounds for data packets transfer in normal mode of operation of RT-MAC protocol. We used state diagram analysis to show the in-depth functioning of RT-MAC protocol. This thesis also presents Markov analysis of RT-MAC that shows the behavior of the protocol in fault scenarios. Extensive simulation results are also presented in this thesis. These results show significant improvement in delay, packet throughput performance, and uniformity in packet transmission pattern at a cost of a very small increase in energy consumption as compared to other real-time MAC protocols such as VTS and general purpose MAC protocols such as S-MAC and T-MAC

Routing and Medium Access Control (MAC) in wireless sensor network for monitoring emergency applications

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonIn recent years, Wireless Sensor Networks (WSNs) have been implemented in many applications including emergency applications. Emergency applications require different characteristics than others, such as robust communication, low energy consumption and minimum end-to-end delay. Routing and Medium Access Control (MAC) are two protocols that have been used by many researchers to achieve those requirements. This thesis mainly focuses on studying distributive clustering routing and MAC protocol for emergency applications. To design robust communication in emergency applications, this thesis has proposed a modified LEACH protocol considering the health status of sensor nodes. LEACH is a benchmark protocol employing distributive clustering-based routing with low energy consumption, however this protocol is not suitable for emergency applications. The health status refers to the condition of nodes, safe or in danger, with the danger status shows the high probability to be destroyed sooner because of external factors such as fire. The proposed approach avoids selecting the nodes in danger as cluster heads. Furthermore, efficient multi-hop communication is employed to minimise energy consumption. The simulation result shows that total data received, energy consumption , packet delivery ratio, and energy efficiency of the proposed approach are stable with an increasing number of destroyed nodes. Furthermore, a grid-based clustering approach with health status is proposed to further enhance energy constraint and robust communication. The proposed approach includes distributive clustering and incorporate constant number of CHs in every round. The remaining energy, the health status of node, and the distance to the centre of the grid are consided when choosing the cluster head. Simulation results have revealed that the proposed protocol has a significant effect on the time for first node to destroy due to energy consumption, an increase of 45% compared to LEACH. Furthermore, packet delivery ratio of the proposed approach is enhanced by 16% compared to LEACH. In order to reduce end to end delay, a priority-based grid Time Division Multiple Access (TDMA) has been proposed. In this approach, traffic is classified into two categories: emergency traffic from danger nodes, and monitoring traffic from safe nodes. This scheme was implemented using three steps: formation of a new TDMA frame, the arrangement of slots and priority allocation. Simulations results showed an improvement of around 65% and 70% in end to end delay compared to Grid and LEACH approaches.Directorate General of Resources for Science, Technology, and Higher Education of Indonesia; the University of Ria