Showing papers on "Multipath routing published in 1979"

A Failsafe Distributed Routing Protocol

Abstract: An algorithm for constructing and adaptively maintaining routing tables in communication networks is presented. The algorithm can be employed in message as well as circuit switching networks, uses distributed computation, provides routing tables that are loop-free for each destination at all times, adapts to changes in network flows, and is completely failsafe. The latter means that after arbitrary failures and additions, the network recovers in finite time in the sense of providing routing paths between all physically connected nodes. For each destination, the routes are independently updated by an update cycle triggered by the destination.

An assignment routing problem

Abstract: This paper examines a routing design problem in which the objective is to assign customer demand points to days of the week in order to solve the resulting node routing problems over the entire week most effectively. The emphasis is on obtaining approximate solutions for this type of combinatorial problem. Several heuristics are developed and tested on a large scale refuse collection problem. Computational results, as well as a discussion of expected benefits, are presented.

On optimum single-row routing

Abstract: The problem of single-row routing represents the backbone of the problem of general routing of multilayer printed circuit boards. In this paper, the necessary and sufficient condition for optimum single-row routing is obtained. By optimum routing we mean minimumm street congestion. A novel formulation is introduced. Examples are given to illustrate how optimum routings are derived. A graph theory interpretation of the condition is also given.

An overview of the new routing algorithm for the ARPANET

Abstract: The original routing algorithm of the ARPANET, in service for over a decade, has recently been removed from the ARPANET and replaced with a new and different algorithm. Although the new algorithm, like the old, is a distributed, adaptive routing algorithm, it is not similar to the old in any other important respect. In the new algorithm, each node maintains a data base describing the delay on each network line. A shortest-path computation is run in each node which explicitly computes the minimum-delay paths (based on the delay entries in the data base) from that node to all other nodes in the network. The average delay on each network line is measured periodically by the nodes attached to the lines. These measured delays are broadcast to all network nodes, so that all nodes use the same data base for performing their shortest-path computations. The new routing algorithm was extensively tested on the ARPANET before being released. This paper describes the algorithm and summarizes the results of these tests.

Optimal Distributed Routing for Virtual Line-Switched Data Networks

Abstract: An algorithm that provides minimum delay routing in a data communication network using virtual line-switching is presented. The algorithm uses distributed computation in the sense that the nodes of the network update their information in an orderly fashion based on messages received from their neighbors. Receipt of these messages also triggers the various steps of the update and rerouting, so that these operations are performed in appropriate sequencing. For stationary input requirements and fixed topology the algorithm reduces network delay at each step and provides loop-free routing in the network. The method also provides an algorithm for quasi-static routing, when the input flows are slowly changing.

The Minimum Width Routing of a 2-Row 2-Layer Polycell-Layout

Abstract: This paper presents a new routing principle that leads to an algorithm to realize the minimum width of the 2-layer channel area between two rows of terminals to be interconnected. Besides the theoretical results, practically applicable routing algorithms based on our principle are developed.

A Routing Algorithm for Signal Processing Networks

Abstract: Algorithms are described here which are suitable for control of a distributed network of signal processors which are interconnected with dedicated paths using decentralized routing control. This paper discusses the algorithm used to implement the processing required at the switching node processor, which can be realized with any of several LSI technologies. Although centralized systems are more efficient in terms of hardware, a single failure in the controller may disable the entire network. This distributed network is implemented with a crossbar switch at each node which facilitates the simultaneous utilization of multiple paths in the network. Index Terms-Computer networks, data routing algorithms, digital signal processing, distributed processing, signal processing networks.

A Practical Method for Vehicle Scheduling

Abstract: The escalating cost per mile of large vehicle operation has increased the advantages of more efficient automatic scheduling. There has been a significant number of articles relating to computerized routing, but the gap between the literature and practice is still very wide. In this paper, the author provides a detailed description of a relatively simple routing algorithm which has been a proven cost saver in a number of applications. The technique can be used for manual routing in smaller firms and is suitable for computer implementation by firms without prior computer routing experience.

A decentralized algorithm for optimal routing in data-communication networks

Abstract: The goal coordination technique of optimization theory for large-scale systems is used to develop a decentralized algorithm for optimal routing in data-communication networks. The algorithm is in two parts of which the first solves the optimal flow assignment problem and the second provides the corresponding optimal routing. All calculations are distributed among the nodes and require information only from adjacent nodes. The results are illustrated via an example and problems for future research are indicated.

A simulation model for network routing

Abstract: The simulation program described in this paper was devised as a vehicle for the study of communication network routing procedures. It was designed to model the behavior of a wide range of network topologies and routing disciplines. An event driven simulation approach was chosen to minimize program development time and complexity.GASP-IV was selected as the simulation language. The determining factor in choosing the language was the clean interface it presents to FORTRAN. The use of GASP-IV permits utilizing the full power of FORTRAN in describing complex routing algorithms while simultaneously relieving the programmer of the responsibility for such essential housekeeping functions as enqueuing and dequeuing messages, file manipulation and event sequencing.As an application of this simulator, a loop-free distributed adaptive routing algorithm is proposed and analyzed. Simulation results are presented and the effect of the algorithm on overall network performance is examined. In addition to a loop-free property, the algorithm is shown to provide a partial solution to the single path routing problem. Furthermore, a modification to the algorithm is given which precludes message loss, and is shown to be superior in performance to current update algorithms (PUA).