Showing papers on "Multipath routing published in 2011"

Coupled Congestion Control for Multipath Transport Protocols

Abstract: Often endpoints are connected by multiple paths, but communications are usually restricted to a single path per connection. Resource usage within the network would be more efficient were it possible for these multiple paths to be used concurrently. Multipath TCP is a proposal to achieve multipath transport in TCP. New congestion control algorithms are needed for multipath transport protocols such as Multipath TCP, as single path algorithms have a series of issues in the multipath context. One of the prominent problems is that running existing algorithms such as TCP New Reno independently on each path would give the multipath flow more than its fair share at a bottleneck link traversed by more than one of its subflows. Further, it is desirable that a source with multiple paths available will transfer more traffic using the least congested of the paths, hence achieving resource pooling. This would increase the overall utilization of the network and also its robustness to failure. This document presents a congestion control algorithm which couples the congestion control algorithms running on different subflows by linking their increase functions, and dynamically controls the overall aggresiveness of the multipath flow. The result is a practical algorithm that is fair to TCP at bottlenecks while moving traffic away from congested links.

Routing in cognitive radio networks: Challenges and solutions

Abstract: Cognitive radio networks (CRNs) are composed of cognitive, spectrum-agile devices capable of changing their configurations on the fly based on the spectral environment. This capability opens up the possibility of designing flexible and dynamic spectrum access strategies with the purpose of opportunistically reusing portions of the spectrum temporarily vacated by licensed primary users. On the other hand, the flexibility in the spectrum access phase comes with an increased complexity in the design of communication protocols at different layers. This work focuses on the problem of designing effective routing solutions for multi-hop CRNs, which is a focal issue to fully unleash the potentials of the cognitive networking paradigm. We provide an extensive overview of the research in the field of routing for CRNs, clearly differentiating two main categories: approaches based on a full spectrum knowledge, and approaches that consider only local spectrum knowledge obtained via distributed procedures and protocols. In each category we describe and comment on proposed design methodologies, routing metrics and practical implementation issues. Finally, possible future research directions are also proposed.

EBRP: Energy-Balanced Routing Protocol for Data Gathering in Wireless Sensor Networks

Abstract: Energy is an extremely critical resource for battery-powered wireless sensor networks (WSN), thus making energy-efficient protocol design a key challenging problem. Most of the existing energy-efficient routing protocols always forward packets along the minimum energy path to the sink to merely minimize energy consumption, which causes an unbalanced distribution of residual energy among sensor nodes, and eventually results in a network partition. In this paper, with the help of the concept of potential in physics, we design an Energy-Balanced Routing Protocol (EBRP) by constructing a mixed virtual potential field in terms of depth, energy density, and residual energy. The goal of this basic approach is to force packets to move toward the sink through the dense energy area so as to protect the nodes with relatively low residual energy. To address the routing loop problem emerging in this basic algorithm, enhanced mechanisms are proposed to detect and eliminate loops. The basic algorithm and loop elimination mechanism are first validated through extensive simulation experiments. Finally, the integrated performance of the full potential-based energy-balanced routing algorithm is evaluated through numerous simulations in a random deployed network running event-driven applications, the impact of the parameters on the performance is examined and guidelines for parameter settings are summarized. Our experimental results show that there are significant improvements in energy balance, network lifetime, coverage ratio, and throughput as compared to the commonly used energy-efficient routing algorithm.

A Decentralized Approach for Anticipatory Vehicle Routing Using Delegate Multiagent Systems

Abstract: Advanced vehicle guidance systems use real-time traffic information to route traffic and to avoid congestion. Unfortunately, these systems can only react upon the presence of traffic jams and not to prevent the creation of unnecessary congestion. Anticipatory vehicle routing is promising in that respect, because this approach allows directing vehicle routing by accounting for traffic forecast information. This paper presents a decentralized approach for anticipatory vehicle routing that is particularly useful in large-scale dynamic environments. The approach is based on delegate multiagent systems, i.e., an environment-centric coordination mechanism that is, in part, inspired by ant behavior. Antlike agents explore the environment on behalf of vehicles and detect a congestion forecast, allowing vehicles to reroute. The approach is explained in depth and is evaluated by comparison with three alternative routing strategies. The experiments are done in simulation of a real-world traffic environment. The experiments indicate a considerable performance gain compared with the most advanced strategy under test, i.e., a traffic-message-channel-based routing strategy.

Intersection-Based Geographical Routing Protocol for VANETs: A Proposal and Analysis

Abstract: This paper presents a class of routing protocols for vehicular ad hoc networks (VANETs) called the Intersection-based Geographical Routing Protocol (IGRP), which outperforms existing routing schemes in city environments. IGRP is based on an effective selection of road intersections through which a packet must pass to reach the gateway to the Internet. The selection is made in a way that guarantees, with high probability, network connectivity among the road intersections while satisfying quality-of-service (QoS) constraints on tolerable delay, bandwidth usage, and error rate. Geographical forwarding is used to transfer packets between any two intersections on the path, reducing the path's sensitivity to individual node movements. To achieve this, we mathematically formulate the QoS routing problem as a constrained optimization problem. Specifically, analytical expressions for the connectivity probability, end-to-end delay, hop count, and bit error rate (BER) of a route in a two-way road scenario are derived. Then, we propose a genetic algorithm to solve the optimization problem. Numerical and simulation results show that the proposed approach gives optimal or near-optimal solutions and significantly improves VANET performance when compared with several prominent routing protocols, such as greedy perimeter stateless routing (GPSR), greedy perimeter coordinator routing (GPCR), and optimized link-state routing (OLSR).

Multipath optimized link state routing for mobile ad hoc networks

Abstract: Multipath routing protocols for Mobile Ad hoc NETwork (MANET) address the problem of scalability, security (confidentiality and integrity), lifetime of networks, instability of wireless transmissions, and their adaptation to applications. Our protocol, called MultiPath OLSR (MP-OLSR), is a multipath routing protocol based on OLSR [1]. The Multipath Dijkstra Algorithm is proposed to obtain multiple paths. The algorithm gains great flexibility and extensibility by employing different link metrics and cost functions. In addition, route recovery and loop detection are implemented in MP-OLSR in order to improve quality of service regarding OLSR. The backward compatibility with OLSR based on IP source routing is also studied. Simulation based on Qualnet simulator is performed in different scenarios. A testbed is also set up to validate the protocol in real world. The results reveal that MP-OLSR is suitable for mobile, large and dense networks with large traffic, and could satisfy critical multimedia applications with high on time constraints.

DBAR: an efficient routing algorithm to support multiple concurrent applications in networks-on-chip

Abstract: With the emergence of many-core architectures, it is quite likely that multiple applications will run concurrently on a system. Existing locally and globally adaptive routing algorithms largely overlook issues associated with workload consolidation. The shortsightedness of locally adaptive routing algorithms limits performance due to poor network congestion avoidance. Globally adaptive routing algorithms attack this issue by introducing a congestion propagation network to obtain network status information beyond neighboring nodes. However, they may suffer from intra- and inter-application interference during output port selection for consolidated workloads, coupling the behavior of otherwise independent applications and negatively affecting performance. To address these two issues, we propose Destination-Based Adaptive Routing (DBAR). We design a novel low-cost congestion propagation network that leverages both local and non-local network information for more accurate congestion estimates. Thus, DBAR offers effective adaptivity for congestion beyond neighboring nodes. More importantly, by integrating the destination into the selection function, DBAR mitigates intra- and inter-application interference and offers dynamic isolation among regions. Experimental results show that DBAR can offer better performance than the best baseline algorithm for all measured configurations; it is well suited for workload consolidation. The wiring overhead of DBAR is low and DBAR provides improvement in the energy-delay product for medium and high injection rates.

Multigate Communication Network for Smart Grid

Abstract: It is envisioned that one of the most important issues in smart grid will be to design a network architecture that is capable of providing secure and reliable two-way communication from meters to other Smart Grid domains. While networking technologies and systems have been greatly enhanced, in wireless communication environments the smart grid faces new challenges in terms of reliability and efficiency. In this paper we present a multigate mesh network architecture to handle real-time traffic for the last mile communication. The paper consists of three parts; multigate routing, real-time traffic scheduling, and multichannel (MC) aided wireless mesh routing. The multigate routing is based on a flexible mesh network architecture that expands on the hybrid tree routing of the IEEE 802.11s. The network is specifically designed to operate in a multi gateway structure in order to meet the smart grid requirements in terms of reliability, self-healing, and throughput performance. This includes developing a timer-based multiple-path diversity scheme that takes advantage of the multi gateway network structure. With respect to packet scheduling, we introduce a novel and efficient scheme that is capable of balancing the traffic load among multiple gateways. The proposed scheme, which is based on the backpressure concept due to its simplicity, is suitable for practical implementation. We also present an MC aided wireless mesh routing protocol which is specifically designed for multigate smart grid networks. The results indicate that a combination of multipath routing and the backpressure-based packet-scheduling scheme can show a significant improvement in the network reliability, latency, and throughput performance. We also show an improvement in the order of magnitude can be achieved via the proposed multichannel aided routing protocol.

Optimization-Based Adaptive Large Neighborhood Search for the Production Routing Problem

Abstract: Operational problems arising in the planning of integrated supply chains have been increasingly studied in the past decade. Among these, the production routing problem (PRP) is a difficult problem that aims to jointly optimize production, inventory, distribution, and routing decisions in order to satisfy the dynamic demand of customers and minimize the overall system cost. This paper introduces an optimization-based adaptive large neighborhood search heuristic for the PRP. In this heuristic, binary variables representing setup and routing decisions are handled by an enumeration scheme and upper-level search operators, respectively, and continuous variables associated with production, inventory, and shipment quantities are set by solving a network flow subproblem. Extensive computational experiments have been performed on benchmark instances from the literature. The results show that our algorithm generally outperforms existing heuristics for the PRP and can produce high-quality solutions in short computin...

An Acknowledgement-Based Approach for the Detection of Routing Misbehaviour in MANETS

Abstract: We are considering the Routing misbehavior in MANETs (Mobile Ad Hoc Networks). Routing protocols for MANETs are based on the assumption which are, all participating nodes are fully cooperative. But, due to the open structure node misbehaviors may exist. One such routing misbehavior is that some nodes will take part in the route discovery and maintenance processes but refuse to forward data packets. In this, we propose the 2ACK scheme that serves as an add-on technique for routing schemes to detect routing misbehavior and to mitigate their effect. The basic idea of the 2ACK scheme is to send two-hop acknowledgment packets in the opposite direction of the routing path. To reduce extra routing overhead, only a few of the received data packets are acknowledged in the 2ACK scheme.

Geographical Routing With Location Service in Intermittently Connected MANETs

Abstract: Combining mobile platforms such as manned or unmanned vehicles and peer-assisted wireless communication is an enabler for a vast number of applications. A key enabler for the applications is the routing protocol that directs the packets in the network. Routing packets in fully connected mobile ad hoc networks (MANETs) has been studied to a great extent, but the assumption on full connectivity is generally not valid in a real system. This case means that a practical routing protocol must handle intermittent connectivity and the absence of end-to-end connections. In this paper, we propose a geographical routing algorithm called location-aware routing for delay-tolerant networks (LAROD), enhanced with a location service, location dissemination service (LoDiS), which together are shown to suit an intermittently connected MANET (IC-MANET). Because location dissemination takes time in IC-MANETs, LAROD is designed to route packets with only partial knowledge of geographic position. To achieve low overhead, LAROD uses a beaconless strategy combined with a position-based resolution of bids when forwarding packets. LoDiS maintains a local database of node locations, which is updated using broadcast gossip combined with routing overhearing. The algorithms are evaluated under a realistic application, i.e., unmanned aerial vehicles deployed in a reconnaissance scenario, using the low-level packet simulator ns-2. The novelty of this paper is the illustration of sound design choices in a realistic application, with holistic choices in routing, location management, and the mobility model. This holistic approach justifies that the choice of maintaining a local database of node locations is both essential and feasible. The LAROD-LoDiS scheme is compared with a leading delay-tolerant routing algorithm (spray and wait) and is shown to have a competitive edge, both in terms of delivery ratio and overhead. For spray and wait, this case involved a new packet-level implementation in ns-2 as opposed to the original connection-level custom simulator.

Model and Protocol for Energy-Efficient Routing over Mobile Ad Hoc Networks

Abstract: Many minimum energy (energy-efficient) routing protocols have been proposed in recent years. However, very limited effort has been made in studying routing overhead, route setup time, and route maintenance issues associated with these protocols. Without a careful design, an energy-efficient routing protocol can perform much worse than a normal routing protocol. In this paper, we first show that the minimum energy routing schemes in the literature could fail without considering the routing overhead involved and node mobility. We then propose a more accurate analytical model to track the energy consumptions due to various factors, and a simple energy-efficient routing scheme PEER to improve the performance during path discovery and in mobility scenarios. Our simulation results indicate that compared to a conventional energy-efficient routing protocol, PEER protocol can reduce up to 2/3 path discovery overhead and delay, and 50 percent transmission energy consumption.

Challenges and techniques for video streaming over mobile ad hoc networks

Abstract: Developments in mobile devices and wireless networking provide the technical platform for video streaming over mobile ad hoc networks (MANETs) However, efforts to realize video streaming over MANETs have met many challenges, which are addressed by several different techniques Examples include cross-layer optimization, caching and replication, and packet prioritization Cross-layer optimization typically leverages multiple description video coding and multipath routing to provide the receiver(s) sufficient video quality Caching and replication add tolerance to disruptions and partitioning In this paper, we identify the challenges of realizing video streaming over MANETs, and analyze and classify the proposed techniques Since 65 % of the identified involve cross-layering design, we study the distribution of joint optimization and parameter exchanges Due to the importance and complexity of evaluating the techniques, we analyze the common methods, indicating that the research domain suffers from a problem of comparability

Survey of Routing Protocols for Mobile Ad-hoc Network

Abstract: Routing is a challenging issue in mobile ad-hoc network. Concerning routing various solutions have been reported. In this context, only few of the proposed solutions are commonly evaluated and less attention has been paid to mention some other schemes. The contribution of this paper is to critically analyze most of the routing protocols which are reported in the available literature. This will help in having a wider understanding of the problem domain and can also be used to develop or some new or to extend already proposed schemes.

A Survey of Routing Attacks and Security Measures in Mobile Ad-Hoc Networks

Abstract: Mobile ad hoc networks (MANETs) are a set of mobile nodes which are self-configuring and connected by wireless links automatically as per the defined routing protocol. The absence of a central management agency or a fixed infrastructure is a key feature of MANETs. These nodes communicate with each other by interchange of packets, which for those nodes not in wireless range goes hop by hop. Due to lack of a defined central authority, securitizing the routing process becomes a challenging task thereby leaving MANETs vulnerable to attacks, which results in deterioration in the performance characteristics as well as raises a serious question mark about the reliability of such networks. In this paper we have attempted to present an overview of the routing protocols, the known routing attacks and the proposed countermeasures to these attacks in various works. ——————————  ——————————

On the feasibility and efficacy of protection routing in IP networks

Abstract: With network components increasingly reliable, routing is playing an ever greater role in determining network reliability. This has spurred much activity in improving routing stability and reaction to failures and rekindled interest in centralized routing solutions, at least within a single routing domain. Centralizing decisions eliminates uncertainty and many inconsistencies and offers added flexibility in computing routes that meet different criteria. However, it also introduces new challenges, especially in reacting to failures where centralization can increase latency. This paper leverages the flexibility afforded by centralized routing to address these challenges. Specifically, we explore when and how standby backup forwarding options can be activated while waiting for an update from the centralized server after the failure of an individual component (link or node). We provide analytical insight into the feasibility of such backups as a function of network structure and quantify their computational complexity. We also develop an efficient heuristic reconciling protectability and performance, and demonstrate its effectiveness in a broad range of scenarios. The results should facilitate deployments of centralized routing solutions.

An abacus turn model for time/space-efficient reconfigurable routing

Abstract: Applications' traffic tends to be bursty and the location of hot-spot nodes moves as time goes by. This will significantly aggregate the blocking problem of wormhole-routed Network-on-Chip (NoC). Most of state-of-the-art traffic balancing solutions are based on fully adaptive routing algorithms which may introduce large time/space overhead to routers. Partially adaptive routing algorithms, on the other hand, are time/space efficient, but lack of even or sufficient routing adaptiveness. Reconfigurable routing algorithms could provide on-demand routing adaptiveness for reducing blocking, but most of them are off-line solutions due to the lack of a practical model to dynamically generate deadlock-free routing algorithms. In this paper, we propose the abacus-turn-model (AbTM) for designing time/space-efficient reconfigurable wormhole routing algorithms. Unlike the original turn model, AbTM exploits dynamic communication patterns in applications to reduce the routing latency and chip area requirements. We apply forbidden turns dynamically to preserve deadlock-free operations. Our AbTM routing architecture has two distinct advantages: First, the AbTM leads to a new router architecture without adding virtual channels and routing table. This reconfigurable architecture updates the routing path once the communication pattern changes, and always provides full adaptiveness to hot-spot directions to reduce network blocking. Secondly, the reconfiguration scheme has a good scalability because all operations are carried out between neighbors. We demonstrate these advantages through extensive simulation experiments. The experimental results are indeed encouraging and prove its applicability with scalable performance in large-scale NoC applications.

A SimPLR method for routability-driven placement

Abstract: Highly-optimized placements may lead to irreparable routing congestion due to inadequate models of modern interconnect stacks and the impact of partial routing obstacles. Additional challenges in routability-driven placement include scalability to large netlists and limiting the complexity of software integration. Addressing these challenges, we develop lookahead routing to give the placer advance, firsthand knowledge of trouble spots, not distorted by crude congestion models. We also extend global placement to (i) spread cells apart in congested areas, and (ii) move cells together in less-congested areas to ensure short, routable interconnects and moderate runtime. While previous work adds isolated steps to global placement, our SIMultaneous PLace-and-Route tool SimPLR integrates a layer- and via-aware global router into a leading-edge, force-directed placer. The complexity of integration is mitigated by careful design of simple yet effective optimizations. On the ISPD 2011 Contest Benchmark Suite, with the official evaluation protocol, SimPLR outperforms every contestant on every benchmark.

Efficient multipath communication for time-critical applications in underwater acoustic sensor networks

Abstract: Due to the long propagation delay and high error rate of acoustic channels, it is very challenging to provide reliable data transfer for time-critical applications in an energy-efficient way. On the one hand, traditional retransmission upon failure usually introduces very large end-to-end delay and is thus not proper for time-critical services. On the other hand, common approaches without retransmission consume lots of energy. In this paper, we propose a new multipath power-control transmission (MPT) scheme, which can guarantee certain end-to-end packet error rate while achieving a good balance between the overall energy efficiency and the end-to-end packet delay. MPT smartly combines power control with multipath routing and packet combining at the destination. With carefully designed power-control strategies, MPT consumes much less energy than the conventional one-path transmission scheme without retransmission. Besides, since no hop-by-hop retransmission is allowed, MPT introduces much shorter delays than the traditional one-path scheme with retransmission. We conduct extensive simulations to evaluate the performance of MPT. Our results show that MPT is highly energy-efficient with low end-to-end packet delays.

Measuring multipath routing in the internet

Abstract: Tools to measure Internet properties usually assume the existence of just one single path from a source to a destination. However, load-balancing capabilities, which create multiple active paths between two end-hosts, are available in most contemporary routers. This paper extends Paris trace route and proposes an extensive characterization of multipath routing in the Internet. We use Paris traceroute from RON and PlanetLab nodes to collect various datasets in 2007 and 2009. Our results show that the traditional concept of a single network path between hosts no longer holds. For instance, 39% of the source-destination pairs in our 2007 traces traverse a load balancer. This fraction increases to 72% if we consider the paths between a source and a destination network. In 2009, we notice a consolidation of per-flow and per-destination techniques and confirm that per-packet load balancing is rare.

A geographical routing protocol for highly-dynamic aeronautical networks

Abstract: Emerging networked systems require domain-specific routing protocols to cope with the challenges faced by the aeronautical environment. We present a geographic routing protocol AeroRP for multihop routing in highly dynamic MANETs. The AeroRP algorithm uses velocity-based heuristics to deliver the packets to destinations in a multi-Mach speed environment. Furthermore, we present the decision metrics used to forward the packets by the various AeroRP operational modes. The analysis of the ns-3 simulations shows AeroRP has several advantages over other MANET routing protocols in terms of PDR, accuracy, delay, and overhead. Moreover, AeroRP offers performance tradeoffs in the form of different AeroRP modes.

Adaptive Routing in Network-on-Chips Using a Dynamic-Programming Network

Abstract: Dynamic routing is desirable because of its substantial improvement in communication bandwidth and intelligent adaptation to faulty links and congested traffic. However, implementation of adaptive routing in a network-on-chip system is not trivial and is further complicated by the requirements of deadlock-free and real-time optimal decision making. In this paper, we present a deadlock-free routing architecture which employs a dynamic programming (DP) network to provide on-the-fly optimal path planning and network monitoring for packet switching. Also, a new routing strategy called k-step look ahead is introduced. This new strategy can substantially reduce the size of routing table and maintain a high quality of adaptation which leads to a scalable dynamic-routing solution with minimal hardware overhead. Our results, based on a cycle-accurate simulator, demonstrate the effectiveness of the DP network, which outperforms both the deterministic and adaptive-routing algorithms in average delay on various traffic scenarios by 22.3%. Moreover, the hardware overhead for DP network is insignificant, based on the results obtained from the hardware implementations.

A low overhead fault tolerant routing scheme for 3D Networks-on-Chip

Abstract: Three-dimensional integrated circuits (3D-ICs) offer a significant opportunity to e nhance the performance of emerging chip multiprocessors (CMPs) using high density stacked device integration and shorter through silicon via (TSV) interconnects that can alleviate some of the problems associated with interconnect scaling in s ub-65nm CMOS technologies. However, network-on-chip (NoC) fabrics that will connect the cores together in 3D-ICs will increasingly be susceptible to permanent and intermittent faults, which can cause catastrophic system failure. To overcome these faults, NoC routing schemes can be enhanced by adding fault tolerance capabilities, so that they can adapt communication flows to follow fault-free paths. Existing work has proposed various fault tolerant routing algorithms for 2D NoCs. In this paper, for the first time, we investigate fault tolerant routing schemes in 3D NoCs. To achieve high arrival rates in the presence of faults, we propose a novel low-overhead fault tolerant routing scheme (4NP-First) for 3D NoCs. The proposed scheme is shown to have better resilience and adaptivity to f aults compared to e xisting dimension-order, turn-model, and stochastic random walk based 2D NoC routing schemes extended to 3D NoCs.

Cluster-based routing protocols in wireless sensor networks: A survey

Abstract: Owing to the limited resources of the sensor nodes, designing energy-efficient routing mechanism to prolong the overall network lifetime becomes one of the most important technologies in wireless sensor networks (WSNs) As an active branch of routing technology, cluster-based routing protocols have proven to be effective in network topology management, energy minimization, data aggregation and so on In this paper, we present a survey of state-of-the-art routing techniques in WSNs We first outline the clustering architecture in WSNs, and classify the proposed approaches based on their objectives and design principles Furthermore, we highlight the challenges in clustering WSNs, including rotating the role of cluster heads, optimization of cluster size and communication mode, followed by a comprehensive survey of routing techniques Finally, the paper concludes with possible future research areas