Showing papers on "Geographic routing published in 2013"
TL;DR: This survey classifies routing problems from the perspective of information quality and evolution and presents a comprehensive review of applications and solution methods for dynamic vehicle routing problems.
1,066 citations
TL;DR: The social properties in DTNs are summarized, some open issues and challenges in social-based approaches regarding the design of DTN routing protocols are discussed, and some of these methods either take advantages of positive social characteristics to assist packet forwarding or consider negative social characteristics such as selfishness.
Abstract: Delay tolerant networks (DTNs) may lack continuous network connectivity. Routing in DTNs is thus challenging since it must handle network partitioning, long delays, and dynamic topology in such networks. In recent years, social-based approaches, which attempt to exploit social behaviors of DTN nodes to make better routing decision, have drawn tremendous interests in DTN routing design. In this article, we summarize the social properties in DTNs, and provide a survey of recent social-based DTN routing approaches. To improve routing performance, these methods either take advantages of positive social characteristics such as community and friendship to assist packet forwarding or consider negative social characteristics such as selfishness. We conclude by discussing some open issues and challenges in social-based approaches regarding the design of DTN routing protocols.
300 citations
TL;DR: A directional routing and scheduling scheme (DRSS) for green vehicle DTNs is presented by using Nash Q-learning approach that can optimize the energy efficiency with the considerations of congestion, buffer and delay.
Abstract: The vehicle delay tolerant networks (DTNs) make opportunistic communications by utilizing the mobility of vehicles, where the node makes delay-tolerant based "carry and forward" mechanism to deliver the packets. The routing schemes for vehicle networks are challenging for varied network environment. Most of the existing DTN routing including routing for vehicular DTNs mainly focus on metrics such as delay, hop count and bandwidth, etc. A new focus in green communications is with the goal of saving energy by optimizing network performance and ultimately protecting the natural climate. The energy---efficient communication schemes designed for vehicular networks are imminent because of the pollution, energy consumption and heat dissipation. In this paper, we present a directional routing and scheduling scheme (DRSS) for green vehicle DTNs by using Nash Q-learning approach that can optimize the energy efficiency with the considerations of congestion, buffer and delay. Our scheme solves the routing and scheduling problem as a learning process by geographic routing and flow control toward the optimal direction. To speed up the learning process, our scheme uses a hybrid method with forwarding and replication according to traffic pattern. The DRSS algorithm explores the possible strategies, and then exploits the knowledge obtained to adapt its strategy and achieve the desired overall objective when considering the stochastic non-cooperative game in on-line multi-commodity routing situations. The simulation results of a vehicular DTN with predetermined mobility model show DRSS achieves good energy efficiency with learning ability, which can guarantee the delivery ratio within the delay bound.
296 citations
TL;DR: A robust soft-state routing protocol that supports opportunistic directional forwarding; and a new framework to attain loop freedom in static and mobile underwater networks to guarantee packet delivery are proposed.
Abstract: Underwater mobile sensor networks have recently been proposed as a way to explore and observe the ocean, providing 4D (space and time) monitoring of underwater environments. We consider a specialized geographic routing problem called pressure routing that directs a packet to any sonobuoy on the surface based on depth information available from on-board pressure gauges. The main challenge of pressure routing in sparse underwater networks has been the efficient handling of 3D voids. In this respect, it was recently proven that the greedy stateless perimeter routing method, very popular in 2D networks, cannot be extended to void recovery in 3D networks. Available heuristics for 3D void recovery require expensive flooding. In this paper, we propose a Void-Aware Pressure Routing (VAPR) protocol that uses sequence number, hop count and depth information embedded in periodic beacons to set up next-hop direction and to build a directional trail to the closest sonobuoy. Using this trail, opportunistic directional forwarding can be efficiently performed even in the presence of voids. The contribution of this paper is twofold: a robust soft-state routing protocol that supports opportunistic directional forwarding; and a new framework to attain loop freedom in static and mobile underwater networks to guarantee packet delivery. Extensive simulation results show that VAPR outperforms existing solutions.
252 citations
TL;DR: This paper aims to provide both a comprehensive and methodical survey of existing literature in the area of geographic routing from its inception as well as acting as an introduction to the subject.
Abstract: Geographic routing offers a radical departure from previous topology-dependent routing paradigms through its use of physical location in the routing process. Geographic routing protocols eliminate dependence on topology storage and the associated costs, which also makes them more suitable to handling dynamic behavior frequently found in wireless ad-hoc networks. Geographic routing protocols have been designed for a variety of applications ranging from mobility prediction and management through to anonymous routing and from energy efficiency to QoS. Geographic routing is also part of the larger area of context-awareness due to its usage of location data to make routing decisions and thus represents an important step in the journey towards ubiquitous computing. The focus of this paper, within the area of geographic routing is on wireless ad-hoc networks and how location information can benefit routing. This paper aims to provide both a comprehensive and methodical survey of existing literature in the area of geographic routing from its inception as well as acting as an introduction to the subject.
215 citations
TL;DR: Linear Programming (LP) model for maximum information extraction and minimum energy consumption is presented in this study and results show that the proposed routing algorithm has less energy consumption and more reliable as compared to Multi-hop communication.
203 citations
11 Nov 2013
TL;DR: ORPL is presented, an opportunistic routing protocol that supports any-to-any, on-demand traffic, and increases robustness and scalability, addressing the whole network reliably through a 64-byte Bloom filter, where RPL needs kilobytes of routing tables for the same task.
Abstract: Routing in battery-operated wireless networks is challenging, posing a tradeoff between energy and latency. Previous work has shown that opportunistic routing can achieve low-latency data collection in duty-cycled networks. However, applications are now considered where nodes are not only periodic data sources, but rather addressable end points generating traffic with arbitrary patterns.We present ORPL, an opportunistic routing protocol that supports any-to-any, on-demand traffic. ORPL builds upon RPL, the standard protocol for low-power IPv6 networks. By combining RPL's tree-like topology with opportunistic routing, ORPL forwards data to any destination based on the mere knowledge of the nodes' sub-tree. We use bitmaps and Bloom filters to represent and propagate this information in a space-efficient way, making ORPL scale to large networks of addressable nodes. Our results in a 135-node testbed show that ORPL outperforms a number of state-of-the-art solutions including RPL and CTP, conciliating a sub-second latency and a sub-percent duty cycle. ORPL also increases robustness and scalability, addressing the whole network reliably through a 64-byte Bloom filter, where RPL needs kilobytes of routing tables for the same task.
159 citations
TL;DR: A survey of the state-of-the-art of proposed multipath routing protocols for WSNs, which are classified into three categories, infrastructure based, non-infrastructure based and coding based, based on the special techniques used in building multiple paths and delivering sensing data.
Abstract: Multipath routing is an efficient technique to route data in wireless sensor networks (WSNs) because it can provide reliability, security and load balance, which are especially critical in the resource constrained system such as WSNs. In this paper we provide a survey of the state-of-the-art of proposed multipath routing protocols for WSNs, which are classified into three categories, infrastructure based, non-infrastructure based and coding based, based on the special techniques used in building multiple paths and delivering sensing data. For each category, we study the design of protocols, analyze the tradeoff of each design, and overview several representing protocols. In addition, we give a summery of design goals, challenges, and evaluation metrics for multipath routing protocols in resource constrained systems in general.
151 citations
TL;DR: Two bounded-length maze routing (BLMR) algorithms are presented that perform much faster routing than traditional maze routing algorithms and a rectilinear Steiner minimum tree aware routing scheme is proposed to guide heuristic-BLMR and monotonic routing to build a routing tree with shorter wirelength.
Abstract: Modern global routers employ various routing methods to improve routing speed and quality Maze routing is the most time-consuming process for existing global routing algorithms This paper presents two bounded-length maze routing (BLMR) algorithms (optimal-BLMR and heuristic-BLMR) that perform much faster routing than traditional maze routing algorithms In addition, a rectilinear Steiner minimum tree aware routing scheme is proposed to guide heuristic-BLMR and monotonic routing to build a routing tree with shorter wirelength This paper also proposes a parallel multithreaded collision-aware global router based on a previous sequential global router (SGR) Unlike the partitioning-based strategy, the proposed parallel router uses a task-based concurrency strategy Finally, a 3-D wirelength optimization technique is proposed to further refine the 3-D routing results Experimental results reveal that the proposed SGR uses less wirelength and runs faster than most of other state-of-the-art global routers with a different set of parameters , , , Compared to the proposed SGR, the proposed parallel router yields almost the same routing quality with average 271 and 312-fold speedup on overflow-free and hard-to-route cases, respectively, when running on a 4-core system
142 citations
TL;DR: This paper analyzes several different types of internal threats that are aimed at the Rank property and study their impact on the performance of the wireless sensor network, and shows that attack in a high forwarding load area will have more impact on network performance than attack in other areas.
Abstract: Routing protocol for low power and lossy networks (RPL) is the underlying routing protocol of 6LoWPAN, a core communication standard for the Internet of Things. RPL outperforms other wireless sensor and ad hoc routing protocols in quality of service (QoS), device management, and energy saving performance. The Rank concept in RPL serves multiple purposes, including route optimization, prevention of loops, and managing control overhead. In this paper, we analyze several different types of internal threats that are aimed at the Rank property and study their impact on the performance of the wireless sensor network. Our analysis raises the question of an RPL weakness, which is the lack of a monitoring parent in every node. In RPL, the child node only receives the parent information through control messages, but it cannot check the services that its parent provide hence it will follow a bad quality route if it has a malicious parent. Our results show that different types of the Rank attacks can be used to intentionally downgrade specific QoS parameters. This paper also reveals that attack in a high forwarding load area will have more impact on network performance than attack in other areas. The defenders can use the knowledge of such correlation between attack location and its impact to set higher security levels at particular positions by monitoring sensitive network parameters and detecting the anomalies.
141 citations
14 Apr 2013
TL;DR: A novel zero-knowledge MSN routing algorithm, homing spread (HS), aimed at using homes to spread messages faster achieves a better performance than existing zero- knowledge MSn routing algorithms, including Epidemic, with a given number of copies, and Spray&Wait.
Abstract: A mobile social network (MSN) is a special delay tolerant network (DTN) composed of mobile nodes with social characteristics. Mobile nodes in MSNs generally visit community homes frequently, while other locations are visited less frequently. We propose a novel zero-knowledge MSN routing algorithm, homing spread (HS). The community homes have a higher priority to spread messages into the network. Theoretical analysis shows that the proposed algorithm can spread a given number of message copies in an optimal way when the inter-meeting times between any two nodes and between a node and a community home follow exponential distributions. We also calculate the expected delivery delay of HS. In addition, extensive simulations are conducted. Results show that community homes are important factors in efficient message spreading. By using homes to spread messages faster, HS achieves a better performance than existing zero-knowledge MSN routing algorithms, including Epidemic, with a given number of copies, and Spray&Wait.
01 Jan 2013
TL;DR: In this paper, a Position based Opportunistic Routing protocol (POR) is proposed to address the problem of delivering data packets for highly dynamic mobile ad hoc networks in a reliable and timely manner.
Abstract: This paper addresses the problem of delivering data packets for highly dynamic mobile ad hoc networks in a reliable and timely manner Most existing ad hoc routing protocols are susceptible to node mobility, especially for large-scale networks Driven by this issue, we propose an efficient Position based Opportunistic Routing protocol (POR) which takes advantage of the stateless property of geographic routing and the broadcast nature of wireless medium When a data packet is sent out, some of the neighbor nodes that have overheard the transmission will serve as forwarding candidates, and take turn to forward the packet if it is not relayed by the specific best forwarder within a certain period of time By utilizing such in-the-air backup, communication is maintained without being interrupted The additional latency incurred by local route recovery is greatly reduced and the duplicate relaying caused by packet reroute is also decreased In case of communication hole, a Virtual Destination based Void Handling (VDVH) scheme is further proposed to work together with POR Both theoretical analysis and simulation results show that POR achieves excellent performance even under high node mobility with acceptable overhead and the new void handling scheme also works well Index Terms-Geographic routing,
TL;DR: Simulation results validate that the proposed LCM significantly outperforms the clustering mechanisms using random selection and by considering only link quality and residual energy in the packet delivery ratio, energy consumption, and delivery latency.
Abstract: In wireless sensor networks, nodes in the area of interest must report sensing readings to the sink, and this report always satisfies the report frequency required by the sink. This paper proposes a link-aware clustering mechanism, called LCM, to determine an energy-efficient and reliable routing path. The LCM primarily considers node status and link condition, and uses a novel clustering metric called the predicted transmission count (PTX), to evaluate the qualification of nodes for clusterheads and gateways to construct clusters. Each clusterhead or gateway candidate depends on the PTX to derive its priority, and the candidate with the highest priority becomes the clusterhead or gateway. Simulation results validate that the proposed LCM significantly outperforms the clustering mechanisms using random selection and by considering only link quality and residual energy in the packet delivery ratio, energy consumption, and delivery latency.
TL;DR: A hop greedy routing scheme that yields a routing path with the minimum number of intermediate intersection nodes while taking connectivity into consideration is proposed and back-bone nodes that play a key role in providing connectivity status around an intersection are introduced.
Abstract: Using advanced wireless local area network technologies, vehicular ad hoc networks (VANETs) have become viable and valuable for their wide variety of novel applications, such as road safety, multimedia content sharing, commerce on wheels, etc. Multihop information dissemination in VANETs is constrained by the high mobility of vehicles and the frequent disconnections. Currently, geographic routing protocols are widely adopted for VANETs as they do not require route construction and route maintenance phases. Again, with connectivity awareness, they perform well in terms of reliable delivery. To obtain destination position, some protocols use flooding, which can be detrimental in city environments. Further, in the case of sparse and void regions, frequent use of the recovery strategy elevates hop count. Some geographic routing protocols adopt the minimum weighted algorithm based on distance or connectivity to select intermediate intersections. However, the shortest path or the path with higher connectivity may include numerous intermediate intersections. As a result, these protocols yield routing paths with higher hop count. In this paper, we propose a hop greedy routing scheme that yields a routing path with the minimum number of intermediate intersection nodes while taking connectivity into consideration. Moreover, we introduce back-bone nodes that play a key role in providing connectivity status around an intersection. Apart from this, by tracking the movement of source as well as destination, the back-bone nodes enable a packet to be forwarded in the changed direction. Simulation results signify the benefits of the proposed routing strategy in terms of high packet delivery ratio and shorter end-to-end delay.
TL;DR: A passive clustering aided routing protocol, named PassCAR, to enhance routing performance in the one-way multi-lane highway scenario and significantly improves the packet delivery ratio and achieves a higher network throughput due to its preference for reliable, stable, and durable routing paths.
TL;DR: A secure routing protocol which adopts the geographical routing principle to cope with the network dimensions, and relies on a distributed trust model for the detection and avoidance of malicious neighbours, capable of defending against an increased set of routing attacks including attacks targeting the indirect trust management scheme.
Abstract: Wireless sensor networks are vulnerable to a wide set of security attacks, including those targeting the routing protocol functionality. The applicability of legacy security solutions is disputable (if not infeasible), due to severe restrictions in node and network resources. Although confidentiality, integrity and authentication measures assist in preventing specific types of attacks, they come at high cost and, in most cases, cannot shield against routing attacks. To face this problem, we propose a secure routing protocol which adopts the geographical routing principle to cope with the network dimensions, and relies on a distributed trust model for the detection and avoidance of malicious neighbours. A novel function which adaptively weights location, trust and energy information drives the routing decisions, allowing for shifting emphasis from security to path optimality. The proposed trust model relies on both direct and indirect observations to derive the trustworthiness of each neighboring node, while it is capable of defending against an increased set of routing attacks including attacks targeting the indirect trust management scheme. Extensive simulation results reveal the advantages of the proposed model.
01 Sep 2013
TL;DR: Results show GeoSVR can provide higher packet delivery ratio with comparable latency to other geographic routing schemes, and the proposed restricted forwarding algorithm overcomes unreliable wireless channel issues.
Abstract: Compared with traditional routing techniques, geographic routing has been proven to be more suitable for highly mobile environments like Vehicular Ad-Hoc Networks (VANETs) because of enhanced scalability and feasibility. These routings use greedy modes or forwarding paths to forward packets. However, the dynamic nature of vehicular network such as frequently changed topology, vehicles density and radio obstacles, could create local maximum, sparse connectivity and network partitions. We propose GeoSVR, a geographic stateless routing combined with node location and digital map. The proposed GeoSVR scheme enhances forwarding path to solve local maximum and sparse connectivity problem, and the proposed restricted forwarding algorithm overcomes unreliable wireless channel issues. In our study, simulations and real world experiments were conducted to evaluate the efficacy and efficiency of the proposed solution. Our results show GeoSVR can provide higher packet delivery ratio with comparable latency to other geographic routing schemes.
31 Dec 2013
TL;DR: This short paper asks 100 network operators about their routing policies, billing models, and thoughts on routing security and reports the survey's results and discusses their implications.
Abstract: Researchers studying the inter-domain routing system typically rely on models to fill in the gaps created by the lack of information about the business relationships and routing policies used by individual autonomous systems. To shed light on this unknown information, we asked 100 network operators about their routing policies, billing models, and thoughts on routing security. This short paper reports the survey's results and discusses their implications.
01 Oct 2013
TL;DR: SlickFlow is presented, a resilient source routing approach implemented with OpenFlow that allows fast failure recovery by combining source routing with alternative path information carried in the packet header, and is evaluated on a prototype implementation based on Open vSwitch.
Abstract: Recent proposals on Data Center Networks (DCN) are based on centralized control and a logical network fabric following a well-controlled baseline topology. The architectural split of control and data planes and the new control plane abstractions have been touted as Software-Defined Networking (SDN), where the OpenFlow protocol is one common choice for the standardized programmatic interface to data plane devices. In this context, source routing has been proposed as a way to provide scalability, forwarding flexibility and simplicity in the data plane. One major caveat of source routing is network failure events, which require informing the source node and can take at least on the order of one RTT to the controller. This paper presents SlickFlow, a resilient source routing approach implemented with OpenFlow that allows fast failure recovery by combining source routing with alternative path information carried in the packet header. A primary and alternative paths are compactly encoded as a sequence of segments written in packet header fields. Under the presence of failures along a primary path, packets can be rerouted to alternative paths by the switches themselves without involving the controller. We evaluate SlickFlow on a prototype implementation based on Open vSwitch and demonstrate its effectiveness in a Mininet emulated scenario for fat-tree, BCube, and DCell topologies.
TL;DR: A mathematical model for optimal routing is formulated, assuming the presence of a global observer that can collect information about all the nodes in the network, and a new protocol based on social grouping among the nodes is proposed to maximize data delivery while minimizing network overhead.
Abstract: Delay tolerant networks (DTN) are characterized by a lack of continuous end-to-end connections due to node mobility, constrained power sources, and limited data storage space of some or all of its nodes. To overcome the frequent disconnections, DTN nodes are required to store data packets for long periods of time until they come near other nodes. Moreover, to increase the delivery probability, they spread multiple copies of the same packet on the network so that one of them reaches the destination. Given the limited storage and energy resources of many DTN nodes, there is a tradeoff between maximizing delivery and minimizing storage and energy consumption. In this paper, we study the routing problem in DTN with limited resources. We formulate a mathematical model for optimal routing, assuming the presence of a global observer that can collect information about all the nodes in the network. Next, we propose a new protocol based on social grouping among the nodes to maximize data delivery while minimizing network overhead by efficiently spreading the packet copies in the network. We compare the new protocol with the optimal results and the existing well-known routing protocols using real life simulations. Results show that the proposed protocol achieves higher delivery ratio and less average delay compared to other protocols with significant reduction in network overhead.
05 Feb 2013
TL;DR: A Genetic algorithm based routing scheme called GAR (Genetic Algorithm-based Routing) that considers the energy consumption issues by minimizing the total distance travelled by the data in every round and is better than the existing techniques in terms of network life time, energy consumption and the totaldistance covered in each round.
Abstract: Routing with energy consideration has paid enormous attention in the field of Wireless Sensor Networks (WSNs). In Some WSNs, some high energy sensors called relay nodes are responsible to route the data towards a base station. Reducing energy consumption of these relay nodes allow us to prolong the lifetime and coverage of the WSN. In this paper, we present a Genetic algorithm based routing scheme called GAR (Genetic Algorithm-based Routing) that considers the energy consumption issues by minimizing the total distance travelled by the data in every round. Our GA based approach can quickly compute a new routing schedule based on the current network state. The scheme uses the advantage of computational efficiency of GA to quickly find out a solution to the problem. The experimental results demonstrate that the proposed algorithm is better than the existing techniques in terms of network life time, energy consumption and the total distance covered in each round.
01 Dec 2013
TL;DR: Numerical results show that Predictive-OLSR significantly outperforms OLSR and BABEL, providing a reliable communication even in very dynamic conditions.
Abstract: In this paper we examine mobile ad-hoc networks (MANET) composed by unmanned aerial vehicles (UAVs). Due to the high-mobility of the nodes, these networks are very dynamic and the existing routing protocols partly fail to provide a reliable communication. We present Predictive-OLSR an extension to the Optimized Link-State Routing (OLSR) protocol: it enables efficient routing in very dynamic conditions. The key idea is to exploit GPS information to aid the routing protocol. Predictive-OLSR weights the expected transmission count (ETX) metric, taking into account the relative speed between the nodes. We provide numerical results obtained by a MAC-layer emulator that integrates a flight simulator to reproduce realistic flight conditions. These numerical results show that Predictive-OLSR significantly outperforms OLSR and BABEL, providing a reliable communication even in very dynamic conditions.
Patent•
23 Jan 2013
TL;DR: In this article, a method of managing undesirable network traffic transmitted from a source node to a destination node over a communications network includes receiving a notification of a routing rule change, authenticating the notification, determining a network routing rule based on the notification and applying the routing rule.
Abstract: Methods, apparatus, and computer readable storage media reduce or eliminate network traffic meeting criteria. In some aspects, network traffic transmitted by one or more source nodes to one or more destination nodes may comprise a denial of service attack against the destination node(s). At least a portion of the denial of service attack traffic may be reduced or eliminated with the disclosed methods and apparatus. In one aspect, a method of managing undesirable network traffic transmitted from a source node to a destination node over a communications network includes receiving a notification of a routing rule change, authenticating the notification, determining a network routing rule based on the notification, applying the network routing rule, determining a network path toward the source node, determining an entity based on the network path, and transmitting a notification of the routing rule change to the entity.
TL;DR: Based on a need for location information, the existing greedy routing protocols are divided into two distinctive categories, namely, location-based and location-free protocols, which are compared with each other based on their features.
Abstract: Due to the significant advances of wireless sensor networks (WSNs), researchers are eager to use this technology in the subsea applications. Because of rapid absorption of high radio frequency in the water, acoustic waves are used as communication medium, which pose new challenges, including high propagation delay, high path loss, low bandwidth, and high-energy consumption. Because of these challenges and high movement of nodes by water flow, end-to-end routing methods used in most of existing routing protocols in WSNs are not applicable to underwater environments. Therefore, new routing protocols have been developed for underwater acoustic sensor networks (UWASNs) in which most of the routing protocols take advantage of greedy routing. Due to inapplicability of global positioning system (GPS) in underwater environments, finding location information of nodes is too costly. Therefore, based on a need for location information, we divided the existing greedy routing protocols into two distinctive categories, namely, location-based and location-free protocols. In addition, location-free category is divided into two subcategories based on method of collecting essential information for greedy routing, including beacon-based and pressure-based protocols. Furthermore, a number of famous routing protocols belonging to each category are reviewed, and their advantages and disadvantages are discussed. Finally, these protocols are compared with each other based on their features.
25 Mar 2013
TL;DR: A novel History Based Prediction Routing protocol for infrastructure-less OppNets which utilizes the behavioral information of the nodes to find the best next node for routing and is compared with the Epidemic routing protocol.
Abstract: In Opportunistic Networks (OppNets), the existence of an end-to-end connected path between the sender and the receiver is not possible. Thus routing in this type of networks is different from the traditional Mobile Adhoc Networks (MANETs). MANETs assume the existence of a fixed route between the sender and the receiver before the start of the communication and till its completion. Routes are constructed dynamically as the source node or an intermediate node can choose any node as next hop from a group of neighbors assuming that it will take the message closer to the destination node or deliver to the destination itself. In this paper, we proposed a novel History Based Prediction Routing (HBPR) protocol for infrastructure-less OppNets which utilizes the behavioral information of the nodes to find the best next node for routing. The proposed protocol was compared with the Epidemic routing protocol. Through simulations it was found that the HBPR performs better in terms of number of messages delivered and the overhead ratio than the Epidemic protocol.
TL;DR: This paper proposes to use the node usage probability, which depends on both the network topology and routing algorithm, to characterize the traffic load distribution, and shows that resource allocation based on the nodes usage probability outperforms the uniform and degree-based allocation scheme.
Abstract: In this paper we study the performance of communication networks from a network science perspective. Our analysis and simulation results reveal the effects of network structure, resource allocation and routing algorithm on the communication performance. Performance parameters, including packet drop rate, time delay, and critical generation rate, are considered. For efficient data transmission, the traffic load should be as uniformly distributed as possible in the network and the average distance of it should be short. We propose to use the node usage probability, which depends on both the network topology and routing algorithm, to characterize the traffic load distribution, and show that resource allocation based on the node usage probability outperforms the uniform and degree-based allocation scheme. On the basis of the proposal analysis and routing algorithms, we compare the performances of regular networks, scale-free networks, random networks, and the Internet constructed at the autonomous system (AS) level. Results from this study provide important insights into the relationship between the structural properties of communication networks and their performances.
TL;DR: A new adaptive routing algorithm built upon the widely studied back-pressure algorithm is developed by decouple the routing and scheduling components of the algorithm by designing a probabilistic routing table that is used to route packets to per-destination queues.
Abstract: Back-pressure-based adaptive routing algorithms where each packet is routed along a possibly different path have been extensively studied in the literature. However, such algorithms typically result in poor delay performance and involve high implementation complexity. In this paper, we develop a new adaptive routing algorithm built upon the widely studied back-pressure algorithm. We decouple the routing and scheduling components of the algorithm by designing a probabilistic routing table that is used to route packets to per-destination queues. The scheduling decisions in the case of wireless networks are made using counters called shadow queues. The results are also extended to the case of networks that employ simple forms of network coding. In that case, our algorithm provides a low-complexity solution to optimally exploit the routing-coding tradeoff.
TL;DR: The vehicular communication problem in urban hybrid networks is addressed and a hybrid routing scheme for data dissemination in VANETs is presented to address and guarantee quality of service (QoS) under various network connectivity and deployment configurations.
Abstract: It is a challenge to design efficient routing protocols for vehicular ad hoc networks (VANETs) because of their highly dynamic properties. We address the vehicular communication problem in urban hybrid networks and present a hybrid routing scheme for data dissemination in VANETs. Location-based crowdsourcing of nearby roadside units (RSUs) has been applied to the infrastructural support of inter-vehicle, vehicle-to-roadside, and inter-roadside communications in hybrid VANETs. The combination of RSU resources and ad hoc networks involves an online probabilistic RSU retrieval algorithm that uses coarse- and fine-grained localization to estimate the number and location of available RSUs; a network coding based multicast routing for dense VANETs using maximum distance separation (MDS) code and local topology information from the forwarding set to achieve robust communication and max-flow min-cut data dissemination; an application of opportunistic routing, using a carry-and-forward scheme to solve the forwarding disconnection problem in sparse VANETs; and a routing switch mechanism to guarantee quality of service (QoS) under various network connectivity and deployment configurations. The performance of our hybrid routing scheme is evaluated using both simulations and real testbed experiments.
TL;DR: This paper discusses how topology management and network application influence the performance of cluster-based and chain-based hierarchical networks, and it is shown that the chain- based HRPs guarantee a longer network lifetime compared to Cluster-based HRPs by three to five times.
Abstract: The routing protocol for Wireless Sensor Networks (WSNs) is defined as the manner of data dissemination from the network field (source) to the base station (destination). Based on the network topology, there are two types of routing protocols in WSNs, they are namely flat routing protocols and hierarchical routing protocols. Hierarchical routing protocols (HRPs) are more energy efficient and scalable compared to flat routing protocols. This paper discusses how topology management and network application influence the performance of cluster-based and chain-based hierarchical networks. It reviews the basic features of sensor connectivity issues such as power control in topology set-up, sleep/idle pairing and data transmission control that are used in five common HRPs, and it also examines their impact on the protocol performance. A good picture of their respective performances give an indication how network applications, i.e whether reactive or proactive, and topology management i.e. whether centralized or distributed would determine the network performance. Finally, from the ensuring discussion, it is shown that the chain-based HRPs guarantee a longer network lifetime compared to cluster-based HRPs by three to five times.
TL;DR: This work considers a distributed total transmit power minimization in a multi-hop single-sink data gathering wireless sensor network by jointly optimizing the resource allocation and the routing with given source rates via cross-layer optimization.
Abstract: We consider a distributed total transmit power minimization in a multi-hop single-sink data gathering wireless sensor network by jointly optimizing the resource allocation and the routing with given source rates. An inherent coupling in optimal routing and resource allocation is taken into account via cross-layer optimization to increase the energy efficiency of the network. Instead of distributing the solution process horizontally by commonly used dual decomposition, we apply consensus optimization in conjunction with the alternating direction method of multipliers (ADMM). By duplicating flow variables, the problem decomposes into node specific subproblems with local variables. These variables are iteratively driven into consensus via the ADMM. Numerical examples show that the proposed algorithm converges significantly faster as compared to the state of the art methods based on the dual decomposition. Additionally, the algorithm is appealing for practical implementation due to its low local communication overhead, robust operation in slightly changing channel conditions and scalability to large networks.