The use of a low-power wake-up radio in wireless sensor networks is considered in this paper, where relevant medium access control solutions are studied. A variety of asynchronous wake-up MAC protocols have been proposed in the literature, which take advantage of integrating a second radio to the main one for waking it up. However, a complete and a comprehensive survey particularly on these protocols is missing in the literature. This paper aims at filling this gap, proposing a relevant taxonomy, and providing deep analysis and discussions. From both perspectives of energy efficiency and latency reduction, as well as their operation principles, state-of-the-art wake-up MAC protocols are grouped into three main categories: 1) duty cycled wake-up MAC protocols; 2) non-cycled wake-up protocols; and 3) path reservation wake-up protocols. The first category includes two subcategories: 1) static wake-up protocols versus 2) traffic adaptive wake-up protocols. Non-cycled wake-up MAC protocols are again divided into two classes: 1) always-on wake-up protocol and 2) radio-triggered wake-up protocols. The latter is in turn split into two subclasses: 1) passive wake-up MAC protocols versus 2) ultra low power active wake-up MAC protocols. Two schemes could be identified for the last category, 1) broadcast based wake-up versus 2) addressing based wake-up. All these classes are discussed and analyzed in this paper, and canonical protocols are investigated following the proposed taxonomy.

MAC Protocols With Wake-Up Radio for Wireless Sensor Networks: A Review

To support multimedia applications, it is desirable that an ad hoc network has a provision of Quality of Service (QoS). However, the provision of QoS in a mobile ad hoc network is a challenging task. In this paper, we present a review of the current research related to the provision of QoS in an ad hoc environment. We examine issues and challenges involved in providing QoS in an ad hoc network. We discuss methods of QoS provisioning at different levels including those at the levels of routing, Medium Access Control (MAC), and cross layer. Also, we discuss schemes for admission control and scheduling that are proposed in the literature for the provision of QoS. We compare salient features of various solutions and approaches and point out directions for future work.

Quality of Service in mobile ad hoc networks: a survey

Capacity and interference aware link scheduling with channel assignment in wireless mesh networks

The overlap of transmission ranges between wireless networks as a result of mobility is referred to as dynamic coexistence. The interference caused by coexistence may significantly affect the performance of wireless body area networks (WBANs) where reliability is particularly critical for health monitoring applications. In this paper, we analytically study the effects of dynamic coexistence on the operation of IEEE 802.15.4-based health monitoring WBANs. The current IEEE 802.15.4 standard lacks mechanisms for effectively managing the coexistence of mobile WBANs. Considering the specific characteristics and requirements of health monitoring WBANs, we propose the dynamic coexistence management (DCM) mechanism to make IEEE 802.15.4-based WBANs able to detect and mitigate the harmful effects of coexistence. We assess the effectiveness of this scheme using extensive OPNET simulations. Our results indicate that DCM improves the successful transmission rates of dynamically coexisting WBANs by 20%-25% for typical medical monitoring applications.

A Distributed Scheme to Manage The Dynamic Coexistence of IEEE 802.15.4-Based Health-Monitoring WBANs

Routing and channel selection from cognitive radio network's perspective

Recent developments in sensor technology, as seen in Berkeley's Mica2 Mote, Rockwell's WINS nodes and the IEEE 802.15.4 Zigbee, have enabled support for single-transceiver, multi-channel communication. The task of channel assignment with minimum interference, also named as the 2-hop coloring problem, allows repetition of colors occurs only if the nodes are separated by more than 2 hops. Being NP complete, development of efficient heuristics for this coloring problem is an open research area and this paper proposes the Dynamic Channel Allocation (DCA) algorithm as a novel solution. Once channels are assigned, a Medium Access Control protocol must be devised so that channel selection, arbitration and scheduling occur with maximum energy savings and reduced message overhead, both critical considerations for sensor networks. The contribution of this paper is twofold: (1) development and analysis of the DCA algorithm that assigns optimally minimum channels in a distributed manner in order to make subsequent communication free from both primary and secondary interference and (2) proposing CMAC, a fully desynchronized multi-channel MAC protocol with minimum hardware requirements. CMAC takes into account the fundamental energy constraint in sensor nodes by placing them in a default sleep mode as far as possible, enables spatial channel re-use and ensures nearly collision free communication. Simulation results reveal that the DCA consumes significantly less energy while giving a legal distributed coloring. CMAC, our MAC protocol that leverages this coloring, has been thoroughly evaluated with various modes in SMAC, a recent protocol that achieves energy savings through coordinated sleeping. Results show that CMAC obtains nearly 200% reduction in energy consumption, significantly improved throughput, and end-to-end delay values that are 50-150% better than SMAC for our simulated topologies.

Nagesh S. Nandiraju

Papers

Channel allocation and medium access control for wireless sensor networks

Adaptive state-based multi-radio multi-channel multi-path routing in Wireless Mesh Networks