TL;DR: The basic concept of Qo SR is introduced, the hot issues of the unicast QoSR heuristics are analyzed and the validity analysis is dissected, including the routing loop problem, stale network state information, the impact of the network topologies and traffic models.
Abstract: It is a challenging problem to provide QoS (quality-of-service) guarantee for the next-generation networks, among which QoSR (QoS routing) is one of the key issues. QoSR seeks to find a feasible path for QoS traffic with two objectives: (1) providing the QoS guarantee for QoS traffic, (2) maximizing the utilization of the whole network. However, some multi-constrained QoSR problems, which are NP-complete, can't be resolved accurately in polynomial time. Thus heuristics are studied extensively in recent years. Based on the weighted graph network model and QoS metrics, the basic concept of QoSR is introduced and the hot issues of the unicast QoSR heuristics are analyzed in this paper. QoSR algorithms can be classified into the several classes: polynomial non-heuristics, pseudo-polynomial non-heuristics, QoS metrics restriction, path subspace search, QoS metrics relation, cost functions study and possibility solution. After typical algorithms are analyzed, the summary and conparison are given for each of the above classes. The validity of algorithms is dissected in detail, including the routing loop problem, stale network state information, the impact of the network topologies and traffic models. Based on the validity analysis, a summary is given for the QoSR algorithms based on probability models. At last, key issues are pointed out to be further studied in the QoSR field.
TL;DR: A less complex, more efficient routing algorithm named as relative identification and direction-based sensor routing (RIDSR) algorithm is proposed, which makes sensor nodes establish more reliable and energy-efficient routing path for data transmission.
Abstract: In studies of wireless sensor networks (WSNs), routing protocols in network layer is an important topic. To date, many routing algorithms of WSNs have been developed such as relative direction-based sensor routing (RDSR). The WSNs in such algorithm are divided into many sectors for routing. RDSR could simply reduce the number of routes as compared to the convention routing algorithm, but it has routing loop problem. In this paper, a less complex, more efficient routing algorithm named as relative identification and direction-based sensor routing (RIDSR) algorithm is proposed. RIDSR makes sensor nodes establish more reliable and energy-efficient routing path for data transmission. This algorithm not only solves the routing loop problem within the RDSR algorithm but also facilitates the direct selection of a shorter distance for routing by the sensor node. Furthermore, it saves energy and extends the lifetime of the sensor nodes. We also propose a new energy-efficient algorithm named as enhanced relative identification and direction-based sensor routing (ERIDSR) algorithm. ERISDR combines triangle routing algorithm with RIDSR. Triangle routing algorithm exploits a simple triangle rule to determine a sensor node that can save more energy while relaying data between the transmitter and the receiver. This algorithm could effectively economize the use of energy in near-sensor nodes to further extend the lifetime of the sensor nodes. Simulation results show that ERIDSR get better performance than RDSR, and RIDSR algorithms. In addition, ERIDSR algorithm could save the total energy in near-sensor nodes more effectively.
TL;DR: The effectiveness of the proposed Proximity Based Energy Efficient Routing (PEER) is demonstrated in as gains attained in terms of improved lifetime, and energy consumption.
Abstract: With efficient routing, Wireless Sensor Networks (WSNs) can provide the continuous transmission with improved lifetime. Different routing protocols account for the different results over the WSNs. WSNs acquire special place in modern day network applications such as body area networks, home animations, cellular enhancement, etc. Especially, focusing on the home automation, a lot of routing algorithms and protocols have been proposed over the years that aim at enhancing the lifetime of such networks. Some of the popular algorithms include Relative Direction Based Sensor Routing (RDSR), Convention Routing (CR), Relative Identification and Direction-Based Sensor Routing (RIDSR), etc. These protocols focus over solving the routing loop problem along with improvement in lifetime of the overall network. However, the gains attained by these networks show a relatively less improvement. Thus, considering the similar problem of routing loop and a lifetime, an energy efficient routing algorithm developed on the backbone of the RIDSR is proposed. The proposed routing algorithm uses the proximity approach to find the appropriate set of nodes for transmission, thus, improving lifetime and resolving routing loop issues. The effectiveness of the proposed Proximity Based Energy Efficient Routing (PEER) is demonstrated in as gains attained in terms of improved lifetime, and energy consumption.
TL;DR: This paper proposes a loop-aware routing protocol for real-world EH-WSNs, called La-CTP, which involves a new parent updating metric and a proactive, adaptive beaconing scheme to effectively suppress the occurrence of loops and unlock unavoidable loops, respectively.
Abstract: In emerging energy-harvesting wireless sensor networks (EH-WSN), the sensor nodes can harvest environmental energy to drive their operation, releasing the user’s burden in terms of frequent battery replacement, and even enabling perpetual sensing systems. In EH-WSN applications, usually, the node in energy-harvesting or recharging state has to stop working until it completes the energy replenishment. However, such temporary departures of recharging nodes severely impact the packet routing, and one immediate result is the routing loop problem. Controlling loops in connectivity-intermittent EH-WSN in an efficient way is a big challenge in practice, and so far, users still lack of effective and practicable routing protocols with loop handling. Based on the Collection Tree Protocol (CTP) widely used in traditional wireless sensor networks, this paper proposes a loop-aware routing protocol for real-world EH-WSNs, called La-CTP, which involves a new parent updating metric and a proactive, adaptive beaconing scheme to effectively suppress the occurrence of loops and unlock unavoidable loops, respectively. We constructed a 100-node testbed to evaluate La-CTP, and the experimental results showed its efficacy and efficiency.
TL;DR: This paper proposes a simple dynamic metrics in respect of link stability, which is loop-free throughout dynamic metric transition and presents a new strategy to achieve loop-freeness with sufficiently low cost for ad hoc networks.
Abstract: To improve communication quality in wireless ad hoc networks, it is definitely important to select stable links as communication paths. To this end, various mobility metrics are presented in the literature. However, the routing loop problem, which is inevitably involved in link-state proactive routing scheme, has not been discussed well. In this paper, we propose a simple dynamic metrics in respect of link stability, which is loop-free throughout dynamic metric transition. Through a theoretical analysis of loop-freeness, we present our new strategy to achieve loop-freeness with sufficiently low cost for ad hoc networks.