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Routing Scheme (routing + scheme)

Distribution by Scientific Domains
Engineering62%

Selected Abstracts

Distributed end-host multicast algorithms for the Knowledge Grid

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 15 2007
Wanqing Tu
Abstract The Knowledge Grid built on top of the peer-to-peer (P2P) network has been studied to implement scalable, available and sematic-based querying. In order to improve the efficiency and scalability of querying, this paper studies the problem of multicasting queries in the Knowledge Grid. An m -dimensional irregular mesh is a popular overlay topology of P2P networks. We present a set of novel distributed algorithms on top of an m -dimensional irregular mesh overlay for the short delay and low network resource consumption end-host multicast services. Our end-host multicast fully utilizes the advantages of an m -dimensional mesh to construct a two-layer architecture. Compared to previous approaches, the novelty and contribution here are: (1) cluster formation that partitions the group members into clusters in the lower layer where cluster consists of a small number of members; (2) cluster core selection that searches a core with the minimum sum of overlay hops to all other cluster members for each cluster; (3) weighted shortest path tree construction that guarantees the minimum number of shortest paths to be occupied by the multicast traffic; (4) distributed multicast routing that directs the multicast messages to be efficiently distributed along the two-layer multicast architecture in parallel, without a global control; the routing scheme enables the packets to be transmitted to the remote end hosts within short delays through some common shortest paths; and (5) multicast path maintenance that restores the normal communication once the membership alteration appears. Simulation results show that our end-host multicast can distributively achieve a shorter delay and lower network resource consumption multicast services as compared with some well-known end-host multicast systems. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Split agent-based routing in interconnected networks

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 4 2004
Constandinos X. Mavromoustakis
Abstract Adaptive behaviour of swarm-based agents (BT Technol. J. 1994; 12:104,113; AAMAS Conference '02, Melbourne, Australia, Month 1,2, 2002; Softcomput. J. 2001; 5(4):313,317.) is being studied in this paper with respect to network throughput for a certain amount of data traffic. Algorithmically complex problems like routing data packets in a network need to be faced with a dynamically adaptive approach such as agent-based scheme. Particularly in interconnected networks where multiple networks are participating in order to figure a large-scale network with different QoS levels and heterogeneity in the service of delay sensitive packets, routing algorithm must adopt in frequent network changes to anticipate such situations. Split agent-based routing technique (SART) is a variant of swarm-based routing (Adapt. Behav. 1997; 5:169,207; Proceedings of 2003 International Symposium on Performance Evaluation of Computer and Telecommunication Systems,SPECTS, Montreal, Canada, July 20,24, 2003; 240,247.) where agents are split after their departure to the next node on a hop-by-hop basis. Packets that are delay sensitive are marked as prioritized which agents recognize-as being a part of a packet- and try to influence the two-way routing tables. Thorough examination is made, for the performance of the proposed algorithm in the network and the QoS offered, taking into account a number of metrics. It is shown that the split agent routing scheme applied to interconnected networks offers a decentralized control in the network and an efficient way to increase overall performance and packet control reducing at the same time the packet loss concept. Copyright © 2004 John Wiley & Sons, Ltd. [source]

An adaptive path routing scheme for satellite IP networks

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 1 2003
Jing Chen
Abstract Mobile satellites can be considered as the promising solution to the global IP network. In order to provide quality of service (QoS) in future networks, mobile satellite can be integrated with the asynchronous transfer mode (ATM) to switch IP datagrams in the space. For such a network, new and sophisticated routing and handoff algorithms are essential. In this paper, a new scheme called adaptive path routing scheme (APRS) is proposed. It is shown that the APRS can provide superior performance for routing and handoff in mobile satellite networks compared with conventional schemes. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Reduced-complexity flow routing models for sinuous single-thread channels: intercomparison with a physically-based shallow-water equation model

EARTH SURFACE PROCESSES AND LANDFORMS, Issue 5 2009
A. P. Nicholas
Abstract Reduced-complexity models of fluvial processes use simple rules that neglect much of the underlying governing physics. This approach is justified by the potential to use these models to investigate long-term and/or fundamental river behaviour. However, little attention has been given to the validity or realism of reduced-complexity process parameterizations, despite the fact that the assumptions inherent in these approaches may limit the potential for elucidating the behaviour of natural rivers. This study presents two new reduced-complexity flow routing schemes developed specifically for application in single-thread rivers. Output from both schemes is compared with that from a more sophisticated model that solves the depth-averaged shallow water equations. This comparison provides the first demonstration of the potential for deriving realistic predictions of in-channel flow depth, unit discharge, energy slope and unit stream power using simple flow routing schemes. It also highlights the inadequacy of modelling unit stream power, shear stress or sediment transport capacity as a function of local bed slope, as has been common practice in a number of previous reduced-complexity models. Copyright © 2009 John Wiley & Sons, Ltd. [source]

An energy-efficient multipath routing protocol for wireless sensor networks

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 7 2007
Ye Ming Lu
Abstract The energy consumption is a key design criterion for the routing protocols in wireless sensor networks. Some of the conventional single path routing schemes may not be optimal to maximize the network lifetime and connectivity. In this paper, we propose a distributed, scalable and localized multipath search protocol to discover multiple node-disjoint paths between the sink and source nodes. We also propose a load balancing algorithm to distribute the traffic over the multiple paths discovered. We compare our proposed scheme with the directed diffusion, directed transmission, N -to-1 multipath routing, and the energy-aware routing protocols. Simulation results show that our proposed scheme has a higher node energy efficiency, lower average delay and control overhead than those protocols. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Static and adaptive routing in ISL networks from a constellation perspective

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 6 2002
Laurent Franck
Abstract This paper presents and evaluates different routing schemes in a constellation of non-geostationary satellites. Routing decisions may or may not take into account the state of the network. While taking into account the network state is likely to bring an improvement in both the network utilization and the quality of service, it also makes the routing architecture more complex. This paper proposes to evaluate the advantages and disadvantages of these different design approaches for routing. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Approximability of unsplittable shortest path routing problems,

NETWORKS: AN INTERNATIONAL JOURNAL, Issue 1 2009
Andreas Bley
Abstract In this article, we discuss the relation of unsplittable shortest path routing (USPR) to other routing schemes and study the approximability of three USPR network planning problems. Given a digraph D = (V,A) and a set K of directed commodities, an USPR is a set of flow paths P, (s,t) , K, such that there exists a metric , = (,a) , Z with respect to which each P is the unique shortest (s,t)-path. In the Min-Con-USPR problem, we seek an USPR that minimizes the maximum congestion over all arcs. We show that this problem is NP-hard to approximate within a factor of O(|V|1,,), but polynomially approximable within min(|A|,|K|) in general and within O(1) if the underlying graph is an undirected cycle or a bidirected ring. We also construct examples where the minimum congestion that can be obtained by USPR is a factor of ,(|V|2) larger than that achievable by unsplittable flow routing or by shortest multipath routing, and a factor of ,(|V|) larger than that achievable by unsplittable source-invariant routing. In the CAP -USPR problem, we seek a minimum cost installation of integer arc capacities that admit an USPR of the given commodities. We prove that this problem is NP-hard to approximate within 2 , , even in the undirected case, and we devise approximation algorithms for various special cases. The fixed charge network design problem FC-USPR, where the task is to find a minimum cost subgraph of D whose fixed arc capacities admit an USPR of the commodities, is shown to be NPO-complete. All three problems are of great practical interest in the planning of telecommunication networks that are based on shortest path routing protocols. Our results indicate that they are harder than the corresponding unsplittable flow or shortest multi-path routing problems. © 2009 Wiley Periodicals, Inc. NETWORKS, 2009 [source]