Research on Neural Network Based QoS Routing

In this paper, the requirements of routing due to the multimedia applications are briefly discussed. In order to solve the QoS constrained routing effectively and efficiently, the scheme of routing based on Hopfield neural network is proposed after the analysis of related work. Then the QoS routing algorithm for unicast based on Hopfield NN is described and the result of emulation is given. At last, multicast QoS routing considerations based on Hopfield NN are proposed.

QoS Routing Algorithm with Multi-Dimensions for Overlay Networks

Overlay networks have emerged as a useful approach to providing a general framework for new applications and services that are to be implemented without significantly changing the IP-layer network infrastructure.Overlay routing has been used as an alternative to the default best effort Internet routing for the absence of end-to-end Quality of Service(QoS). While the former has recently been investigated, the conflict of QoS restraints and resource optimization remains unsolved. Recent studies have shown that overlay paths can give better latency, loss rate and TCP throughput. In this paper, a multi-dimensional QoS objective model based on the analysis of multiple QoS constraints has been presented, and a routing algorithm to optimise the overlay resource of its nodes and links is then proposed.In fact, the algorithm obtained multiple QoS values using probability theory to achieve the routing according to the multi-dimensional QoS objective vector of the QoS objective model. Simulation results reveals that the algorithm works better than other existing algorithms in balancing the network resources, and applications with stringent QoS requirements could be run.

Optimized QoS Routing Algorithm

QoS routing is one of the key technologies for providing guaranteed service in IP networks. The paper focuses on the optimization problem for bandwidth constrained QoS routing, and proposes an optimal algorithm based on the global optimization of path bandwidth and hop counts. The main goal of the algorithm is to minimize the consumption of network resource, and at the same time to minimize the network congestion caused by irrational path selection. The simulation results show that our algorithm has lower call blocking rate and higher throughput than traditional algorithms.

Combining Single (Mixed) Metric Approach and Genetic Algorithm for QoS Routing Problem

A hybrid algorithm for the delay constrained least cost path problem is proposed through combination of single (mixed) metric approach and genetic algorithm. Compared with the known genetic algorithm for the same problem, the new algorithm adopts integral coding scheme and new genetic operator, which reduces the search space and improves the efficiency of genetic operation. Meanwhile, the single (mixed) approach accelerates the convergence speed. Simulation results indicate that the proposed algorithm can find near-optimal even optimal solutions within moderate numbers of generations.

SIMULATED ANNEALING BASED POLYNOMIAL TIME QOS ROUTING ALGORITHM FOR MANETS

Multi-constrained Quality-of-Service (QoS) routing is a big challenge for Mobile Ad hoc Networks (MANETs) where the topology may change constantly. In this paper a novel QoS Routing Algorithm based on Simulated Annealing (SA_RA) is proposed. This algorithm first uses an energy function to translate multiple QoS weights into a single mixed metric and then seeks to find a feasible path by simulated annealing. The pa- per outlines simulated annealing algorithm and analyzes the problems met when we apply it to Qos Routing (QoSR) in MANETs. Theoretical analysis and experiment results demonstrate that the proposed method is an effective approximation algorithms showing better performance than the other pertinent algorithm in seeking the (approximate) optimal configuration within a period of polynomial time.

Multiple constraints-based QoS multicast routing: model and algorithms

Constraint-based multicast routing, which aims at identifying a path that satisfies a set of quality of service (QoS) constraints, has became a very important research issue in the areas of networks and distributed systems. In general, multi-constrained path selection with or without optimization is a NP-complete problem that can not be exactly solved in polynomial time. Hence, accurate constraints-based routing algorithms with a fast running time are scarce, perhaps even non-existent. The expected impact of such a constrained-based routing algorithm has resulted in the proposal of numerous heuristics and a few exact QoS algorithms. This paper aims to give a thorough, concise and fair evaluation of the most important multiple constraint-based QoS multicast routing algorithms known today, and it provides a descriptive overview and simulation results of these multi-constrained routing algorithms.

QoS Routing Optimization Strategy Using Genetic Algorithm in Optical Fiber Communication Networks

This paper describes the routing problems in optical fiber networks, definesfive constraints, induces and simplifies the evaluation function and fitness function, and proposesa routing approach based on the genetic algorithm, which includes an operator [OMO] to solve the QoSrouting problem in optical fiber communication networks. The simulation results show that theproposed routing method by using this optimal maintain operator genetic algorithm (OMOGA) issuperior to the common genetic algorithms (CGA). It not only is robust and efficient but alsoconverges quickly and can be carried out simply, that makes it better than other complicated GA.

QoS routing based on mobile agent for LEO satellite IP networks

Current quality of service（QoS） routing schemes for low earth orbit（LEO） satellites IP networks either neglect the varying population density or fail to guarantee end-to-end delay.As a remedy,QoS routing protocol based on mobile agent（QoSRP-MA） is proposed.QoSRP-MA is a source-based routing protocol.Once connection requests arrive,QoS mobile agents are dispatched from ingress satellite to explore routes,which migrate using satellite routing tables.Upon arriving in egress satellite,QoS mobile agents migrate back towards ingress satellite to reserve bandwidth.To construct satellite routing tables,load balancing routing algorithm based on mobile agent（LBRA-MA） is presented.In LBRP-MA,at regular intervals mobile agents launched on all satellites migrate autonomously to evaluate path cost and update routing tables.Moreover,path cost between source and destination is evaluated considering satellite geographical position as well as inter-satellite link（ISL） cost.Furthermore,ISL congestion index is considered to update routing table.Through simulations on a Courier-like constellation,it shows that QoSRP-MA can achieve guaranteed end-to-end delay bound with higher throughput,lower connection failing ratio and signaling overhead compared to high performance satellite routing（HPSR） scheme.

Study on the performance of the A*Prune QoS routing algorithm for intelligent optical networks and its improvements

The A＇Prune quality of service （QoS） routing algorithm was proposed to compute K-shortest paths satisfying multiple QoS constraints, The A＇Prune is considered to be one of the practical routing algorithms for intelligent optical networks because of its flexibility in handling many practical constraints, This article gives detailed performance studies of the algorithm through extensive simulation experiments. We found that both the running time and the memory space requirements of the algorithm are large, especially when the network size increases, in this article, we also propose an approach to improving the performance of the A＇Prune algorithm. The improvements should make the A＇Prune algorithm more attractive for practical use in intelligent optical networks.

A Heuristic Algorithm for QoS Multicast Routing

In recent years, QoS multicast routing has continued to be a very important research topic in the areas of networks. This paper presents a heuristic algorithm for the QoS multicast routing (HAQMR). This heuristic algorithm deals with delay and bandwidth constraints and has low cost. The HAQMR attempts to significantly reduce the overhead for constructing a multicast tree, the proof for correctness of the HAQMR is given, and the performance of the HAQMR is evaluated by simulations. The study shows that HAQMR provides an available approach to QoS multicast routing.

Void Aware Position Based Opportunistic Routing for QoS in Mobile Ad Hoc Networks

The unique anywhere, anytime wireless communication support offers, tremendous potential for the next generation of applications in a Mobile Ad-hoc Network (MANET). The Quality of Service (QoS) has been the ever demanding task of wireless communication to satisfy the application requirements. Geographical routing employs a greedy forwarding technique to deliver the packets to the destination and to owe the communication void, it fails to render the expected level of QoS. Opportunistic routing technique effectively utilizes the advantages of broadcasting nature of the wireless medium and selects a set of forwarding candidates instead of relying on a greedy node. To improve the efficiency of QoS routing in sparse and highly dynamic network topology, this paper proposes the Void-Aware Position based Opportunistic Routing (VAPOR). The VAPOR maintains 2-hop neighbor information to take a routing decision, but it is limited to 1-hop information when the node density is high. It efficiently balances the storage overhead and communication delay due to void and it increases the network throughput even under a sparse network. To provide a certain assurance level for packet reachability, VAPOR decides the potential forwarders based on the forwarding probability that measures link stability, capacity, and connectivity factor. It adaptively favors a path that avoids frequent link failure and unreliable link usage. By limiting the propagation area of duplicate packets, VAPOR reduces wastage of network resources, and ittakes the advantage of concurrent batch forwarding to avoid further duplication and unnecessary delay.

Multicast routing algorithm of multiple QoS based on widest-bandwidth

A multicast routing algorithm of multiple QoS constraints based on widest-bandwidth （MRQW） which takes available bandwidth as the prime metric, considering the constraints of the surplus energy of the node, delay and delay jitter, is presented. The process of routing based on MRQW is provided for as well. Correctness proof and the complexity analysis of the MRQW are also given in the paper. Simulation results show that the MRQW has a good performance in creating multicast trees. It not only satisfys multiple QoS constraints but also makes multicast links have larger available bandwidth

New Ad Hoc QoS Multicast Routing Protocol

The application environments of wireless Ad hoc networks require that it should support Quality of Service (QoS). However, that is very difficult because of the inherent characteristics of the wireless channel and the frequent changes of network topology caused by nodes movement. An Ad hoc QoS Multicasting (AQM) protocol can solve this problem by previously reserving the neighbor nodes for tracking resource availability. By considering QoS restrictions of transport delay, loss ratio, bandwidth requirement, delay jitter, and throughout, and by finding the adaptive routing, the AQM protocol can obviously improve the efficiency of multicastsession. The results of network simulation show that QoS is essentially applicable to Ad hoc networks.

A distributed on-demand bandwidth-constrained multicast routing protocol for wireless ad hoc networks

To meet the bandwidth requirement for the multicasting data flow in ad hoc networks, a distributed on- demand bandwidth-constrained multicast routing （BCMR） protocol for wireless ad hoc networks is proposed. With this protocol, the resource reservation table of each node will record the bandwidth requirements of data flows, which access itself, its neighbor nodes and hidden nodes, and every node calculates the remaining available bandwidth by deducting the bandwidth reserved in the resource reservation table from the total available bandwidth of the node. Moreover, the BCMR searches in a distributed manner for the paths with the shortest delay conditioned by the bandwidth constraint. Simulation results demonstrate the good performance of BCMR in terms of packet delivery reliability and the delay. BCMR can meet the requirements of real time communication and can be used in the multicast applications with low mobility in wireless ad hoc networks.

Quality of Service Routing Strategy Using Supervised Genetic Algorithm

A supervised genetic algorithm (SGA) is proposed to solve the quality of service (QoS) routing problems in computer networks. The supervised rules of intelligent concept are introduced into genetic algorithms (GAs) to solve the constraint optimization problem. One of the main characteristics of SGA is its searching space can be limited in feasible regions rather than infeasible regions. The superiority of SGA to other GAs lies in that some supervised search rules in which the information comes from the problems are incorporated into SGA. The simulation results show that SGA improves the ability of searching an optimum solution and accelerates the convergent process up to 20 times.

An Algorithm Based on Mobile Agent for Delay Constrained Least Cost Unicast Routing

The delay constrained least cost path problem with imprecise delay information is discussed, and a distributed heuristic algorithm without any assumption of imprecise state information is presented. The algorithm employs mobile agents to search feasible paths in parallel and requires limited network state information kept at each node. The simulations indicate that the presented solution provides better call acceptance probability and better fairness between short paths and long paths. And the algorithm can tolerate high degree of delay imprecision.

Internet QoS: Architectures, Strategies and Mechanisms

As an extensive study of Internet QoS, a framework for emerging Internet QoS strategies is presented. Integrated service (Intserv/RSVP), Differentiated service (Diffserv), MPLS, and QoS routing, are overviewed. The key issues and relationship of these QoS architectures are discussed. Some algorithms in IP QoS implementation and unsolved problems are also studied in this paper. Furthermore, a new strategies of incorporating Intserv with Diffserv to archive end-to-end QoS is proposed. It is also discussed why MPLS and QoS routing are introduced into this framework, how they differ from and relate to other schemes and where they fit into the Diffserv architecture. The timescales of different QoS strategies are also studied and some proposals for QoS routing deployment are given.

Trade-off between accuracy, cost, and QoS using a beacon-on-demand strategy and Kalman filtering over a VANET

Vehicular Ad-hoc Networks （VANETs） have been suggested as an active and powerful field of research to mitigate environmental problems and challenges. The main challenge in a VANET is to ensure routing with a good Quality of Service （QoS）. The Greedy Perimeter Stateless Routing （GPSR） protocol is one of the most promising position- based routing mechanisms used to overcome this challenge. Its effectiveness depends entirely on the information on a node＇s mobility and the precision of this information. By broadcasting periodic beaconing within trans- mission boundary ranges, GPSR can manage neighbors＇ mobility information and maintain up-to-date lists of neighbours. Nevertheless, information on the position of a neighboring vehicle quickly becomes outdated, which negatively influences the efficiency of the routing. In order to monitor information mobility and to increase the QoS in this challenging area, position estimation needs to he considered. Thus, in this study, we examine the position estimation problem, and propose an improvement to the GPSR protocol, named KF-GPSR, where each vehicle estimates in real time the position of its neighbors using the Kalman filter algorithm. Indeed, by employing this strong estimation technique, it is possible to reduce consid- erably the frequency of exchanged beacon packets, while maintaining high position accuracy. For greater reliability, we also propose an extension to KF-GPSR, called BOD-KF-GPSR, that uses the ＂beacon-on-demand＂ process only if a node needs to rediscover its neighborhood. Simulation experiments using the network simulator NS-2 are presented to demonstrate the ability and usefulness of our two proposals. Here, we compare the pro- posed protocols against diverse common protocols： GPSR, AODV, DSR, and ZRP. The results show that BOD-KF- GPSR achieves a significant enhancement in terms of its packet delivery ratio, routing cost, normalized routing load, end-to-end delay, and throughput.

Improved ant colony-based multi-constrained QoS energy-saving routing and throughput optimization in wireless Ad-hoc networks

In order to establish a route supporting multi-constrained quality of service（QoS）, increase network throughput and reduce network energy consumption, an improved ant colony-based multi-constrained QoS energy-saving routing algorithm（IAMQER） is proposed. The ant colony algorithm, as one of the available heuristic algorithms, is used to find the optimal route from source node to destination node. The proposed IAMQER algorithm, which is based on the analysis of local node information such as node queue length, node forwarding number of data packets and node residual energy, balances the relationship between the network throughput and the energy consumption, thus improving the performance of network in multi-constrained QoS routing. Simulation results show that this IAMQER algorithm can find the QoS route that reduce average energy consumption and improves network packet delivery ratio under the end-to-end delay and packet loss ratio constraints.

Fuzzy Logic QoS Dynamic Source Routing for Mobile Ad Hoc Networks

Considering the characters of dynamic topology and the imprecise state information in mobile ad hoc network,we propose a Fuzzy Logic QoS Dynamic Source Routing(FLQDSR)algorithm based on Dynamic Source Routing(DSR)protocol while adopting fuzzy logic to select the appropriate QoS routing in multiple paths which are searched in parallel.This scheme considers not only the bandwidth and end-to-end delay of routing,but also the cost of the path.On the otherhand the merit of using fuzzy logic is that it can be implemented by hardware.This makes the realization of the schemeeasier and faster.However our algorithm is based on DSR,the maximal hop count should be less than 10,i.e.,the scaleof mobile ad hoc network should not be very large.Simulation results show that FLQDSR can tolerate a high degree of in-formation imprecision by adding the fuzzy logic module which integrates the QoS requirements of application and the rout-ing QoS parameters to determine the most qualified one in every node.