Equal-cost multi-path routing

About: Equal-cost multi-path routing is a research topic. Over the lifetime, 10472 publications have been published within this topic receiving 249362 citations.

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.

Robust cooperative routing protocol in mobile wireless sensor networks

Abstract: In wireless sensor networks, path breakage occurs frequently due to node mobility, node failure, and channel impairments It is challenging to combat path breakage with minimal control overhead, while adapting to rapid topological changes Due to the Wireless Broadcast Advantage (WBA), all nodes inside the transmission range of a single transmitting node may receive the packet, hence naturally they can serve as cooperative caching and backup nodes if the intended receiver fails to receive the packet In this paper, we present a distributed robust routing protocol in which nodes work cooperatively to enhance the robustness of routing against path breakage We compare the energy efficiency of cooperative routing with noncooperative routing and show that our robust routing protocol can significantly improve robustness while achieving considerable energy efficiency

HYMN: A Novel Hybrid Multi-Hop Routing Algorithm to Improve the Longevity of WSNs

Abstract: Power-aware routing in Wireless Sensor Networks (WSNs) is designed to adequately prolong the lifetime of severely resource-constrained ad hoc wireless sensor nodes}. Recent research has identified the energy hole problem in single sink-based WSNs, a characteristic of the many-to-one (convergecast) traffic patterns. In this paper, we propose HYbrid Multi-hop routiNg (HYMN) algorithm, which is a hybrid of the two contemporary multi-hop routing algorithm architectures, namely, flat multi-hop routing that utilizes efficient transmission distances, and hierarchical multi-hop routing algorithms that capitalizes on data aggregation. We provide rigorous mathematical analysis for HYMN-optimize it and model its power consumption. In addition, through extensive simulations, we demonstrate the effective performance of HYMN in terms of superior connectivity.

Hypercube message routing in the presence of faults

Abstract: We discuss the problem of routing messages on hypercubes which have faulty processors and/or communication links. We are motivated by the belief that simple algorithms, operating under simple assumptions, can ensure high probabilities of successful message routing. In this paper, we consider the basic problem of routing a single message from an arbitrary source to an arbitrary destination. In our study, a fault is assumed to render the processor or link non-functional for purposes of communicating messages. As such, we may also consider communications hot spots as node faults, and our results also apply to routing in congested hypercubes.A framework for the analysis of fault tolerant routing schemes on a hypercube is presented. This framework includes differing routing schemes, routing information models and fault distribution models. The a priori probabilities of successful routing of a single, indivisible message under each of our possible sets of assumptions are calculated. Using random routing, under the one-step local information routing model, we show that the a priori probability of successful message routing is high even for an exceedingly large number of faults. We also analyze the behavior of sidetracking, a routing method which combines the concepts of local information and randomization. Using sidetracking, and in the one-step local information routing model, a message will be routed forward using random routing. If the message reaches a blocked processor (no non-faulty neighbors along a minimal path to the destination) it will be sent to a non-faulty neighbor, chosen uniformly at random from the set of non-faulty neighbors. We use simulation experiments to determine the performance of this routing scheme, analyzing the probability of successful routing and the expected path length of a routed message. The empirical performance of the sidetracking algorithms indicates strongly that, in the limit as the cube dimension grows larger and for a fixed probability of node failure, the probability of successful message routing is 100%.

The temporal and topological characteristics of BGP path changes

Abstract: BGP has been deployed in Internet for more than a decade. However, the events that cause BGP topological changes are not well understood. Although large traces of routing updates seen in BGP operation are collected by RIPE RlS and University of Oregon RouteViews, previous work examines this data set as individual routing updates. This paper describes methods that group routing updates into events. Since one event (a policy change or peering failure) results in many update messages, we cluster updates both temporally and topologically (based on the path vector information). We propose a new approach to analyzing the update traces, classifying the topological impact of muting events, and approximating the distance to the autonomous system originating the event. Our analysis provides some insight into routing behavior: First, at least 45% path changes are caused by events on transit peerings. Second, a significant number (23-37%) of path changes are transient, in that routing updates indicate temporary path changes, but they ultimately converge on a path that is identical from the previously stable path. These observations suggest that a content provider cannot guarantee end-to-end routing stability based solely on its relationship with its immediate ISP, and that better detection of transient changes may improve routing stability.