Showing papers on "Hazy Sighted Link State Routing Protocol published in 1992"
01 Apr 1992
TL;DR: This paper provides the simplest known support for deadlock-free adaptive routing in k-ary n-cubes of more than two dimensions (with k > 2) and restricts adaptivity reduces the hardware complexity, improving router speed or allowing additional performance-enhancing network features.
Abstract: Network throughput can be increased by allowing multipath, adaptive routing. Adaptive routing allows more freedom in the paths taken by messages, spreading load over physical channels more evenly. The flexibility of adaptive routing introduces new possibilities of deadlock. Previous deadlock avoidance schemes in k-ary n-cubes require an exponential number of virtual channels, independent of network size and dimension. Planar adaptive routing algorithms reduce the complexity of deadlock prevention by reducing the number of choices at each routing step. In the fault-free case, planar-adaptive networks are guaranteed to be deadlock-free. In the presence of network faults, the planar-adaptive router can be extended with misrouting to produce a working network which remains provably deadlock free and is provably livelock free. In addition, planar adaptive networks can simultaneously support both in-order and adaptive, out-of-order packet delivery.Planar-adaptive routing is of practical significance. It provides the simplest known support for deadlock-free adaptive routing in k-ary n-cubes of more than two dimensions (with k > 2). Restricting adaptivity reduces the hardware complexity, improving router speed or allowing additional performance-enhancing network features. The structure of planar-adaptive routers is amenable to efficient implementation.
464 citations
Patent•
27 Aug 1992TL;DR: In this article, the authors propose an internetworking apparatus which handles a scale of a network flexibly without degrading high-speed operation, where a router manager and a plurality of routing accelerator modules for performing routing are connected to one another through a high speed bus.
Abstract: An internetworking apparatus which handles a scale of a network flexibly without degrading high speed operation. A router manager and a plurality of routing accelerator modules for performing routing are connected to one another through a high speed bus, and a plurality of communication ports are connected to the respective routing accelerators independently of one another. The plurality of routing accelerators can perform the routing for reception data packet at high speed. If more routing accelerators are provided, the disposal to the networks having a small scale to a large scale can be readily realized.
101 citations
Patent•
01 Jun 1992TL;DR: In this paper, a self-timed message routing chip is coupled to each processor node, thereby forming a two dimensional mesh of message routing chips, and data can broadcast through the mesh routing chips to a row, a column, or a matrix of nodes.
Abstract: A method and apparatus providing for data broadcasting in a two dimensional mesh of processor nodes is disclosed. In accordance with the present invention, a self-timed message routing chip is coupled to each processor node, thereby forming a two dimensional mesh of message routing chips. Broadcasting originates from a corner node, and data can broadcast through the mesh routing chips to a row, a column, or a matrix of nodes. The mesh routing chips, together, form a self-timed pipeline with each individual message routing chip having broadcasting hardware which provides for the forking of a message within that particular message routing chip. The self-timed forking of a message within individual message routing chips directly supports data broadcasting within the two dimensional mesh.
71 citations
TL;DR: This paper presents an optimal algorithm for packet routing on a mesh-connected computer and shows how a single step of inter-processor communication can be thought of as a packet routing task.
51 citations
01 Jun 1992
TL;DR: It is shown, using a recently developed network simulator, MaRS, that a newly proposed distance-vector algorithm (ExBF) performs as well as SPF, suggesting that distance- vector algorithms are appropriate for very large wide-area networks.
Abstract: There are two approaches to adaptive routing protocols for wide-area store-and-forward networks: distance-vector and link-state. Distance-vector algorithms use O(N x e) storage at each node, whereas link-state algorithms use O(N2), where N is the number of nodes in the network and e is the average degree of a node. The ARPANET started with a distance-vector algorithm (Distributed Bellman-Ford), but because of long-lived loops, changed to a link-state algorithm (SPF). We show, using a recently developed network simulator, MaRS, that a newly proposed distance-vector algorithm (ExBF) performs as well as SPF. This suggests that distance-vector algorithms are appropriate for very large wide-area networks.
49 citations
06 Dec 1992
TL;DR: An approach to adaptive routing in multirate networks using a Markov decision theoretic framework which maintains low computational complexity while still providing quite accurate routing information is proposed.
Abstract: An approach to adaptive routing in multirate networks using a Markov decision theoretic framework which maintains low computational complexity while still providing quite accurate routing information is proposed. In this approach, each link is modeled as a birth-death process to reduce the state space size and a policy iteration applied to achieve better network performance. The results show that routing algorithms based on this approach yield better performance than least-load path routing (LLP) without incurring any significant increase in computational complexity. >
45 citations
01 May 1992
TL;DR: The authors propose a new scheme for optical signal routing within linear lightwave network (LLN) subnets, based on a new optical agent signal routing scheme, called rooted routing, and shows that when the link and excess losses are small, the optimal power budget is close to thatWhen the original, shortest path routing scheme is used.
Abstract: The authors propose a new scheme for optical signal routing within linear lightwave network (LLN) subnets. They study the synchronization problem that exists in these subnets which prevents efficient implementation of time division multiple access schemes for sharing a common broadcast medium. A solution for this problem is proposed, based on a new optical agent signal routing scheme, called rooted routing. The impact of the rooted routing on power losses is analyzed, and an approach for optimizing the power losses in LLNs with rooted routing is presented. It is shown that when the link and excess losses are small, the optimal power budget is close to that when the original, shortest path routing scheme is used. It is also shown that the power budget in LLNs with rooted routing can be significantly improved using a single optical amplifier. >
30 citations
TL;DR: The design, the implementation, and the performance results of a routing algorithm which provides deadlock-free communication in a tightly coupled message-passing concurrent computer are described.
Abstract: This paper describes the design, the implementation, and the performance results of a routing algorithm which provides deadlock-free communication in a tightly coupled message-passing concurrent computer. The algorithm is adaptive, isolated and uses the store-and-forward technique. It allows message communication between two processes regardless of where they are physically located on the network. The routing algorithm has many positive characteristics including provable deadlock freedom, guaranteed message arrival, and automatic local congestion reduction. It can be used as a basis for the design of high-level communication primitives. An Occam implementation on a network of inmos Transputers is discussed. The experimental results show that the routing algorithm is effective to support process to process communication on a concurrent computer.
11 citations
11 Oct 1992
TL;DR: The results obtained using the enhanced JEB network show that the problem of optimal message routing can successfully by solved through the application of neural networks.
Abstract: The authors investigate the possibility of using an artificial neural network as an adaptive message router to provide optimal or near-optimal routing paths. Two different neural network architectures are implemented and tested against a network simulator to ascertain if their performance is adequate to allow them to be used as routing controllers in a network. A network simulator was written to investigate the performance of the JEB net of Jensen, Eshera, and Barash (1990) and the Hopfield net in routing messages. The results obtained using the enhanced JEB network show that the problem of optimal message routing can successfully by solved through the application of neural networks. >
9 citations
01 Apr 1992
TL;DR: This paper analysis storage complexity of the IDRP protocol and suggests possible local techniques for reducing it.
Abstract: IDRP is an inter-domain routing protocol that is based on the path-vector routing algorithm. This paper analysis storage complexity of the protocol and suggests possible local techniques for reducing it.
8 citations
01 Apr 1992
TL;DR: The steady-state response of link-state and loop-free distance-vector routing algorithms to multiple changes in the costs of links is investigated and suggests that it may be possible to correlate the performance of the routing algorithms with various parameters that can be used to characterize networks.
Abstract: The steady-state response of link-state and loop-free distance-vector routing algorithms to multiple changes in the costs of links is investigated. A quantitative comparison of an ideal link-state algorithm similar to the one used in the open shortest path first (OSPF) and in the OSI intradomain routing protocol, and a new loop-free distance-vector algorithm, is made for several computer network topologies. A variety of quantities, including the length of messages and the average number of paths affected by routing loops, are computed as a function of time after a link or node change. Probabilities of various conditions, including the existence of loops, are also obtained as a function of time. The results show that in steady state, a loop-free distance-vector algorithm operates with essentially the same communication overhead as the ideal link state algorithm, and requires substantially fewer CPU cycles. The results also suggest that it may be possible to correlate the performance of the routing algorithms with various parameters that can be used to characterize networks. >
10 May 1992
TL;DR: The results of performance evaluation of the packet delay show that the MARION protocol is outperformed by the DOR/FRAN protocol, which could therefore be considered to be more suitable for PROMETHEUS applications with real-time requirements.
Abstract: The results of a performance evaluation by analysis using Markov models of the adaptive multihop routing protocols DOR/FRAN and MARION for access from vehicles to an infrastructure network are presented. In the Markov model for the direction-oriented routing protocol (DOR/FRAN) implicit ACKs and retransmissions are taken into account. It is shown that the Markov model of the MARION protocol, which becomes more complex as the number of direct neighbors of a station increases, can be simplified if a large number of direct neighbors is assumed. The probability that a transmitted packet reaches the next beacon is calculated. The results of performance evaluation of the packet delay show that the MARION protocol is outperformed by the DOR/FRAN protocol, which could therefore be considered to be more suitable for PROMETHEUS applications with real-time requirements, and to be an appropriate adaptive multihop routing protocol candidate for the network layer of an integrated vehicle-vehicle and vehicle-beacon communication network. >