Integrated topology control and routing in wireless sensor networks for prolonged network lifetime

This study considers an integrated topology control and routing problem in wireless sensor networks (WSNs), which are employed to gather data via use of sensors with limited energy resources. We employ a hierarchical topology and routing structure with multiple sinks and devise a topology control scheme via usable energy fraction at the sensors. We develop and examine three different mathematical models whose solutions prescribe clusterhead and sink locations and data routing from sensors to sinks in a period of a deployment cycle. We develop a heuristic solution algorithm which provides very small optimality gaps for the models. The approach utilizes two types of solution representations, a combination of multiple neighborhoods, and objective value-based cut inequalities for improving the evaluation of candidate solutions. We present extensive numerical test results and analysis of the models and the solution approach. We determine that our proposed model, which minimizes average energy usage and the range of remaining energy distribution at the sensors, captures important characteristics of topology control and routing integration in WSN design and exhibits significantly better performance than our benchmark models and a well-known protocol HEED in extending network lifetime.     

An MAC protocol supporting multiple traffic over mobile ad hoc networks

This letter presents the design and performance of a multi-channel MAC protocol that supports multiple traffics for IEEE 802.11 mobile ad-hoc networks.The dynamic channel selection scheme by receiver decision is implemented and the number of the data channel is independent of the network topology.The priority for real-time traffic is assured by the proposed adaptive back off algorithm and different IFS.The protocol is evaluated by simulation and the results have shown that it can support multiple traffics and the performance is better than the performance that IEEE 802.11 standard provides.     

Novel service protocol for supporting remote and mobile users in wireless sensor networks with multiple static sinks

A wireless sensor network typically consists of users, a sink, and a number of sensor nodes. The users may be remotely connected to a wireless sensor network and via legacy networks such as Internet or Satellite the remote users obtain data collected by the sink that is statically located at a border of the wireless sensor network. However, in practical sensor network applications, there might be two types of users: the traditional remote users and mobile users such as firefighters and soldiers. The mobile users may move around sensor fields and they communicate with the static sink only via the wireless sensor networks in order to obtain data like location information of victims in disaster areas. For supporting the mobile users, existing studies consider temporary structures. However, the temporary structures are constructed per each mobile user or each source nodes so that it causes large energy consumption of sensor nodes. Moreover, since some of them establish the source-based structure, sinks in them cannot gather collective information like mean temperature and object detection. In this paper, to effectively support both the remote users and the mobile users, we propose a novel service protocol relying on the typical wireless sensor network. In the protocol, multiple static sinks connect with legacy networks and divide a sensor field into the number of the multiple sinks. Through sharing queries and data via the legacy networks, the multiple static sinks provide high throughput through distributed data gathering and low latency through short-hops data delivery. Multiple static sinks deliver the aggregated data to the remote users via the legacy networks. In case of the mobile users, when a mobile user moves around, it receives the aggregated data from the nearest static sink. Simulation results show that the proposed protocol is more efficient in terms of energy consumption, data delivery ratio, and delay than the existing protocols.     

DDRP: An efficient data‐driven routing protocol for wireless sensor networks with mobile sinks

Introduction of mobile sinks into a wireless sensor network can largely improve the network performance. However, sink mobility can cause unexpected changes of network topology, which may bring excessive protocol overhead for route maintenance and may offset the benefit from using mobile sinks. In this paper, we propose an efficient data‐driven routing protocol (DDRP) to address this problem. The design objective is to effectively reduce the protocol overhead for data gathering in wireless sensor networks with mobile sinks. DDRP exploits the broadcast feature of wireless medium for route learning. Specifically, each data packet carries an additional option recording the known distance from the sender of the packet to target mobile sink. The overhearing of transmission of such a data packet will gratuitously provide each listener a route to a mobile sink. Continuous such route‐learning among nodes will provide fresh route information to more and more nodes in the network. When no route to mobile sink is known, random walk routing simply is adopted for data packet forwarding. Simulation results show that DDRP can achieve much lower protocol overhead and longer network lifetime as compared with existing work while preserving high packet delivery ratio. Copyright © 2012 John Wiley & Sons, Ltd.     

End-to-End Adaptive QoS Provisioning over GPRS Wireless Mobile Network

The General Packet Radio Service (GPRS) offers performance guaranteed packet data services to mobile users over wireless frequency-division duplex links with time division multiple access, and core packet data networks. This paper presents a dynamic adaptive guaranteed Quality-of-Service (QoS) provisioning scheme over GPRS wireless mobile links by proposing a guaranteed QoS media access control (GQ-MAC) protocol and an accompanying adaptive prioritized-handoff call admission control (AP-CAC) protocol to maintain GPRS QoS guarantees under the effect of mobile handoffs. The GQ-MAC protocol supports bounded channel access delay for delay-sensitive traffic, bounded packet loss probability for loss-sensitive traffic, and dynamic adaptive resource allocation for bursty traffic with peak bandwidth allocation adapted to the current queue length. The AP-CAC protocol provides dynamic adaptive prioritized admission by differentiating handoff requests with higher admission priorities over new calls via a dynamic multiple guard channels scheme, which dynamically adapts the capacity reserved for dealing with handoff requests based on the current traffic conditions in the neighboring radio cells. Integrated services (IntServ) QoS provisioning over the IP/ATM-based GPRS core network is realized over a multi-protocol label switching (MPLS) architecture, and mobility is supported over the core network via a novel mobile label-switching tree (MLST) architecture. End-to-end QoS provisioning over the GPRS wireless mobile network is realized by mapping between the IntServ and GPRS QoS requirements, and by extending the AP-CAC protocol from the wireless medium to the core network to provide a unified end-to-end admission control with dynamic adaptive admission priorities.     

Cross‐layer design for topology control and routing in MANETs

A mobile ad hoc network (MANET) is a self‐organized and adaptive wireless network formed by dynamically gathering mobile nodes. Since the topology of the network is constantly changing, the issue of routing packets and energy conservation become challenging tasks. In this paper, we propose a cross‐layer design that jointly considers routing and topology control taking mobility and interference into account for MANETs. We called the proposed protocol as Mobility‐aware Routing and Interference‐aware Topology control (MRIT) protocol. The main objective of the proposed protocol is to increase the network lifetime, reduce energy consumption, and find stable end‐to‐end routes for MANETs. We evaluate the performance of the proposed protocol by comprehensively simulating a set of random MANET environments. The results show that the proposed protocol reduces energy consumption rate, end‐to‐end delay, interference while preserving throughput and network connectivity. Copyright © 2010 John Wiley & Sons, Ltd.     

A Swarm-Intelligence-Based Protocol for Data Acquisition in Networks with Mobile Sinks

This paper addresses the problem of data acquisition in ad hoc and sensor networks with mobile sinks and proposes a protocol based on swarm intelligence, SIMPLE, to route data in such environments. The proposed protocol is based on a swarm agent that integrates the residual energy of nodes into the route selection mechanism and maximizes the network's lifetime by evenly balancing the residual energy across nodes and minimizing the protocol overhead. The protocol is robust and scales well with both the network size and in the presence of multiple sinks. An information theoretic lower bound on the protocol overhead associated with the swarm agent advertisement is also obtained. SIMPLE is also shown to have a lower message complexity compared to similar algorithms previously proposed in literature. Simulation results are used to verify SIMPLE's performance and robustness and also to demonstrate its superior performance over existing algorithms.     

Dynamic proxy tree-based data dissemination schemes for wireless sensor networks

In wireless sensor networks, efficiently disseminating data from a dynamic source to multiple mobile sinks is important for the applications such as mobile target detection and tracking. The tree-based multicasting scheme can be used. However, because of the short communication range of each sensor node and the frequent movement of sources and sinks, a sink may fail to receive data due to broken paths, and the tree should be frequently reconfigured to reconnect sources and sinks. To address the problem, we propose a dynamic proxy tree-based framework in this paper. A big challenge in implementing the framework is how to efficiently reconfigure the proxy tree as sources and sinks change. We model the problem as on-line constructing a minimum Steiner tree in an Euclidean plane, and propose centralized schemes to solve it. Considering the strict energy constraints in wireless sensor networks, we further propose two distributed on-line schemes, the shortest path-based (SP) scheme and the spanning range-based (SR) scheme. Extensive simulations are conducted to evaluate the schemes. The results show that the distributed schemes have similar performance as the centralized ones, and among the distributed schemes, the SR scheme outperforms the SP scheme.     

Hybrid routing and load balancing protocol for wireless sensor network

In wireless sensor network, when the nodes are mobile, the network structure keeps on changing dynamically, that is, new nodes enter the network and old members exit the network. As a result, the path from one node to the other varies from time to time. In addition, if the load on a particular part of the network is high, then the nodes will not be capable of transmitting the data. Thus, data delivery at the destination will be unsuccessful. Moreover, the part of the network involved in transmitting the data should not be overloaded. To overcome these issues, a hybrid routing protocol and load balancing technique is discussed in this paper for the mobile data collectors in which the path from source to destination is ensured before data transmission. The hybrid routing protocol that combines the reactive and proactive approach is used to enhance gradient based routing protocol for low power and lossy networks. This protocol can efficiently handle the movement of multiple sinks. Finally, load balancing is applied over the multiple mobile elements to balance the load of sensor nodes. Simulation results show that this protocol can increase the packet delivery ratio and residual energy with reduced delay and packet drop.     

Anycast tree-based routing in mobile wireless sensor networks with multiple sinks

A routing scheme for wireless sensor networks with mobile sensors and mobile multiple sinks is proposed and studied. The scheme is based on expanding ring search, anycast messaging and reactive mode with maintaining route state information in sensors. As a result of a successful routing request issued by the sensor, it becomes a member of a routing tree with some sink as a root. Anycast messaging is used only at the stage of establishing a path from a sensor to a sink. Replies from sinks are always forwarded in unicast mode. This considerably reduces network traffic and, as a result, energy consumption by sensors. To take into account routing conditions for network nodes in receiving messages from different directions, the receiving area of each node is assumed to consist of a number of sectors, considered as independent links with random change of link states in time. The proposed routing scheme was investigated with the use of a detailed simulation model, implemented in terms of a class of extended Petri nets. In simulation the following performance metrics were investigated versus time-to-live value: response ratio, relative network traffic and relative energy consumption. These metrics were considered for a number of combinations of parameters, such as the number of sinks, sensor availability and link availability. The results of simulation were compared with published characteristics of a similar model, in which sensors do not maintain any routing state information, and is proved to outperform it.     

Energy efficient adaptive optical CDMA random access protocol based on particle swarm optimization

In this paper, an energy efficient adaptive optical code division multiple access (OCDMA) random access protocol based on particle swarm optimization (PSO) is described. This protocol is based on the S-ALOHA with power and rate allocation based on PSO. This scheme evaluates jointly optimal power and rate allocation PSO based under the random access protocol as a new and simplified scheme for high performance, high energy efficiency suitable for OCDMA systems. The aim is to maximize the aggregate throughput, subject to predetermined quality of service restrictions and energy efficiency constraint in terms of the signal-to-noise-plus interference ratio of each user class. Numerical results are discussed taking into account realistic network operation scenario.     

A Tracking-Assisted Routing Scheme for Wireless Sensor Networks

Wireless sensor networks (WSNs) offer much promise for target tracking and environmental monitoring. While many WSN routing protocols have been proposed to date, most of these focus on the mobility of observers and assume that targets are fixed. However, in reality, many applications require for sensing data to be propagated from multiple mobile targets to multiple mobile observers. In addition, WSNs often operate under strict energy constraints, and therefore reducing energy dissipation is also an important issue. In this paper, we present a grid-based routing scheme known as TRENS. First, we address the issue of the WSN comprising multiple mobile targets and observers—with TRENS being the first scheme of its kind to use tracking technology to increase the efficiency of routing procedures in the context of dynamic topology. Next, we introduce a shortcutting approach to resolve energy issues by optimizing routing paths and thus decreasing communication costs and latency. Finally, we conduct extensive simulations to show how TRENS conserves energy and performs better than other grid-based schemes.     

基于路径分段的MANET自适应多径路由协议

采用多径路由机制能够有效保证Ad hoc网络数据包传输成功概率,提高网络可靠性。该文在路径数量分析的基础上,根据分组丢弃概率门限判决方法,提出了基于路径分段的自适应多径路由协议。节点采用预先设定的门限值判定链路状态,并且根据网络当前的拓扑状态自适应地选择中继节点,建立路径分段的多径路由。仿真结果表明,该机制在合理利用网络资源的同时能够有效保障数据包的可靠传输,更加适用于状态时变的Ad hoc网络。     

A mobile sink path planning for wireless sensor networks based on priority‐ordered dependent nonparametric trees

The professional design of the routing protocols with mobile sink(s) in wireless sensor networks (WSNs) is important for many purposes such as maximizing energy efficiency, increasing network life, and evenly distributing load balance across the network. Moreover, mobile sinks ought to first collect data from nodes which have very important and dense data so that packet collision and loss can be prevented at an advanced level. For these purposes, the present paper proposes a new mobile path planning protocol by introducing priority‐ordered dependent nonparametric trees (PoDNTs) for WSNs. Unlike traditional clustered or swarm intelligence topology‐based routing methods, a topology which has hierarchical and dependent infinite tree structure provides a robust link connection between nodes, making it easier to reselect ancestor nodes (ANs). The proposed priority‐ordered infinite trees are sampled in the specific time frames by introducing new equations and hierarchically associated with their child nodes starting from the root node. Hence, the nodes with the highest priority and energy that belong to the constructed tree family are selected as ANs with an opportunistic approach. A mobile sink simply visits these ANs to acquire data from all nodes in the network and return to where it started. As a result, the route traveled is assigned as the mobile path for the current round. We have performed comprehensive performance analysis to illustrate the effectiveness of the present study using NS‐2 simulation environment. The present routing protocol has achieved better results than the other algorithms over various performance metrics.     

A quadtree-based hierarchical data dissemination for mobile sensor networks

The envisioned sensor network architecture where some of the nodes may be mobile poses several new challenges to this special type of ad hoc wireless network. Recently, researchers have proposed several data dissemination protocols based on either some hierarchical structure mainly constructed by a source node or source/sink oriented dissemination tree to support mobile sinks. However, such a source-initiated hierarchical structure results in significant resource consumption as the number of source-sink pairs are increased. Additionally, stimulus mobility aggravates the situation, where several sources may build a separate data forwarding hierarchy along the stimulus moving path. In this paper, we propose a new data dissemination protocol that exploits “Quadtree-based network space partitioning” to provide more efficient routing among multiple mobile stimuli and sink nodes. A common hierarchy of cluster-head nodes is constructed where the data delivery to mobile sinks is independent of the current position of mobile stimuli. Therefore, the overhead needed for hierarchy (route) maintenance is lower. Simulation results show that our work significantly reduces average energy consumption while maintaining comparably higher data delivery ratio.     

无线传感器网络S-MAC协议的时延控制

S—MAC协议是基于竞争的传感器网络MAC层协议，通过使节点空闲时自动转换为休眠状态来节省能耗。然而，休眠模式的引入导致了数据前传中断问题，使时延显著增加。时延问题使得S—MAC协议不能理想地应用于实时数据采集系统中。在S—MAC中引入了快速数据前传算法（FDF），仿真表明，采用FDF算法的S—MAC协议比采用自适应侦听算法的S—MAC协议显著减少了时延（对于10跳的网络，端到端的时延减少了将近一倍），因而显著地增加了网络的吞吐量。     

Energy-Aware Data Aggregation for Grid-Based Wireless Sensor Networks with a Mobile Sink

Wireless sensor networks (WSNs) are made up of many small and highly sensitive nodes that have the ability to react quickly. In WSNs, sink mobility brings new challenges to large-scale sensor networks. Almost all of the energy-aware routing protocols that have been proposed for WSNs aim at optimizing network performance while relaying data to a stationary gateway (sink). However, through such contemporary protocols, mobility of the sink can make established routes unstable and non-optimal. The use of mobile sinks introduces a trade-off between the need for frequent rerouting to ensure optimal network operation and the desire to minimize the overhead of topology management. In this paper, in order to reduce energy consumption and minimize the overhead of rerouting frequency, we propose an energy-aware data aggregation scheme (EADA) for grid-based wireless sensor networks with a mobile sink. In the proposed scheme, each sensor node with location information and limited energy is considered. Our approach utilizes location information and selects a special gateway in each area of a grid responsible for forwarding messages. We restrict the flooding region to decrease the overhead for route decision by utilizing local information. We conducted simulations to show that the proposed routing scheme outperforms the coordination-based data dissemination scheme (CODE) (Xuan, H. L., & Lee, S. Proceedings of the Sensor Networks and Information Processing Conference, pp. 13–18, 2004).     

Segmentation of multiple objects evolving conditional random field based topology adaptive active membrane

In this paper we have used conditional random field based learning scheme to differentiate the spectral signature of the objects and background in a scene. The overall objective is to segment multiple objects in a poorly contrasted scene. The primary tool for segmentation is a region based active membrane which evolves under image based external energy. The learning scheme helps in splitting the active membrane for segmenting multiple objects and integrates the topology adaptive property of the active membrane with the architecture and evolution of the membrane. The proposed approach is tested in a challenging application domain of estimation of sizes of oil sand rocks.     

Rendezvous-based data dissemination for supporting mobile sinks in multi-hop clustered wireless sensor networks

In wireless sensor networks, a clustering-based technique is considered as an efficient approach for supporting mobile sinks without using position information. It exploits a Backbone-based Virtual Infrastructure (BVI) which uses only cluster heads (CHs) to construct routing structures. Since sensor nodes have constrained energy and are failure-prone, the effective design of both a clustering structure to construct a BVI and a routing protocol in the BVI is an important issue to achieve energy-efficient and reliable data delivery. However, since previous studies use one-hop clustering for a BVI, they are not robust against node and link failures and thus leading low data delivery ratio. They also use flooding-based routing protocols in a BVI and thus leading high energy consumption. Thus, in this paper, we propose a rendezvous-based data dissemination protocol based on multi-hop clustering (RDDM). Since RDDM uses a multi-hop clustering to provide enough backup sensor nodes to substitute a CH and enough backup paths between neighbor CHs, it can provide high robustness against node and link failures. By using a rendezvous CH, RDDM constructs routing paths from source nodes to mobile sinks without flooding in our BVI and thus can save energy of sensor nodes. By considering movement types of sinks, RDDM finds out a shorter path between a source node and a mobile sink through signaling only between neighbor CHs and thus can reduce the energy consumption. Analysis and simulation results show that RDDM provides better performance than previous protocols in terms of energy consumption and data delivery ratio.     

Designing power aware self-reconfiguring topology for mobile wireless personal area networks using fuzzy logic

In mobile wireless personal area networks (WPAN), the position of each node changes over time. A network protocol that is able to dynamically update its links in order to maintain strong connectivity is said to be "self-reconfiguring." We propose a mobile wireless personal area networks (WPAN) design method with self-reconfiguring protocol for power efficiency. The WPAN is self-organized to clusters using an unsupervised clustering method, fuzzy c-means. A fuzzy logic system is applied to master/controller election for each cluster. A self-reconfiguring topology is proposed to manage the mobility and recursively update the network topology. We also modify the mobility management scheme with hysteresis to overcome the ping-pong effect. Simulation results show that our scheme performs much better than the existing algorithm.