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.

Data funneling: routing with aggregation and compression for wireless sensor networks

Abstract: This paper considers the problem of minimizing the amount of communication needed to send readings from a set of sensors to a single destination in energy constrained wireless networks. Substantial gains can be obtained using packet aggregation techniques while routing. The proposed routing algorithm, called Data Funneling, allows the network to considerably reduce the amount of energy spent on communication setup and control, an important concern in low data-rate communication. This is achieved by sending only one data stream from a group of sensors to the destination instead of having an individual data stream from each sensor to the destination. Doing so also reduces the probability of packet collisions in the wireless medium because the same amount of information can be transmitted by having fewer nodes send longer packets. Additional gains can be realized by efficient compression of data. This is achieved by losslessly compressing the data by encoding information in the ordering of the sensors' packets. This "coding by ordering" scheme compresses data by suppressing certain readings and encoding their values in the ordering of the remaining packets. Using these techniques together can more than halve the energy spent in communication.

Fixed-alternate routing and wavelength conversion in wavelength-routed optical networks

Abstract: Consider an optical network which employs wavelength-routing crossconnects that enable the establishment of wavelength-division-multiplexed (WDM) connections between node pairs. In such a network, when there is no wavelength conversion, a connection is constrained to be on the same wavelength channel along its route. Alternate routing can improve the blocking performance of such a network by providing multiple possible paths between node pairs. Wavelength conversion can also improve the blocking performance of such a network by allowing a connection to use different wavelengths along its route. This work proposes an approximate analytical model that incorporates alternate routing and sparse wavelength conversion. We perform simulation studies of the relationships between alternate routing and wavelength conversion on three representative network topologies. We demonstrate that alternate routing generally provides significant benefits, and that it is important to design alternate routes between node pairs in an optimized fashion to exploit the connectivity of the network topology. The empirical results also indicate that fixed-alternate routing with a small number of alternate routes asymptotically approaches adaptive routing in blocking performance.

Multipath routing in the presence of frequent topological changes

Abstract: In this article we propose a framework for multipath routing in mobile ad hoc networks and provide its analytical evaluation. The instability of the topology (e.g., failure of links) in these types of networks, due to nodal mobility and changes in wireless propagation conditions, makes transmission of time-sensitive information a challenging problem. To combat this inherent unreliability of these networks, we propose a routing scheme that uses multiple paths simultaneously by splitting the information among the multitude of paths, to increase the probability that the essential portion of the information is received at the destination without incurring excessive delay. Our scheme works by adding some overhead to each packet, which is calculated as a linear function of the original packet bits. The resulting packet (information and overhead) is fragmented into smaller blocks and distributed over the available paths. Our goal is, given the failure probabilities of the paths, to find the optimal way to fragment and then distribute the blocks to the paths so that the probability of reconstructing the original information at the destination is maximized. Our algorithm has low time complexity, which is crucial since the path failure characteristics vary with time and the optimal block distribution has to be recalculated in real time.

Mobile agents for adaptive routing

Abstract: This paper introduces AntNet, a new routing algorithm for telecommunication networks. AntNet is an adaptive, distributed, mobile-agents-based algorithm which was inspired by recent work on the ant colony metaphor. We apply AntNet in a datagram network and compare it with both static and adaptive state-of-the-art routing algorithms. We ran experiments for various paradigmatic temporal and spatial traffic distributions. AntNet showed both very good performances and robustness under all the experimental conditions with respect to its competitors.

Increasing Internet Capacity Using Local Search

Abstract: Open Shortest Path First (OSPF) is one of the most commonly used intra-domain internet routing protocol. Traffic flow is routed along shortest paths, splitting flow evenly at nodes where several outgoing links are on shortest paths to the destination. The weights of the links, and thereby the shortest path routes, can be changed by the network operator. The weights could be set proportional to the physical lengths of the links, but often the main goal is to avoid congestion, i.e. overloading of links, and the standard heuristic recommended by Cisco (a major router vendor) is to make the weight of a link inversely proportional to its capacity. We study the problem of optimizing OSPF weights for a given a set of projected demands so as to avoid congestion. We show this problem is NP-hard, even for approximation, and propose a local search heuristic to solve it. We also provide worst-case results about the performance of OSPF routing vs. an optimal multi-commodity flow routing. Our numerical experiments compare the results obtained with our local search heuristic to the optimal multi-commodity flow routing, as well as simple and commonly used heuristics for setting the weights. Experiments were done with a proposed next-generation AT&T WorldNet backbone as well as synthetic internetworks.