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An Overview of QualityofService Routing for the Next Generation HighSpeed Networks: Problems and Solutions
"... The upcoming Gbps highspeed networks are expected to support a wide range of communicationintensive, realtime multimedia applications. The requirement for timely delivery of digitized audiovisual information raises new challenges for the next generation integratedservice broadband networks. On ..."
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Cited by 223 (22 self)
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The upcoming Gbps highspeed networks are expected to support a wide range of communicationintensive, realtime multimedia applications. The requirement for timely delivery of digitized audiovisual information raises new challenges for the next generation integratedservice broadband networks. One of the key issues is the QualityofService (QoS) routing. It selects network routes with sufficient resources for the requested QoS parameters. The goal of routing solutions is twofold: (1) satisfying the QoS requirements for every admitted connection and (2) achieving the global efficiency in resource utilization. Many unicast/multicast QoS routing algorithms were published recently, and they work with a variety of QoS requirements and resource constraints. Overall, they can be partitioned into three broad classes: (1) source routing, (2) distributed routing and (3) hierarchical routing algorithms. In this paper we give an overview of the QoS routing problem as well as the existing solutions. We present the strengths and the weaknesses of different routing strategies and outline the challenges. We also discuss the basic algorithms in each class, classify and compare them, and point out possible future directions in the QoS routing area.
On Finding Multiconstrained Paths
, 1998
"... New emerging distributed multimedia applications provide guaranteed endtoend quality of service (QoS) and have stringent constraints on delay, delayjitter, cost, etc. The task of QoS routing is to find a route in the network which has sufficient resources to satisfy the constraints. The delaycost ..."
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Cited by 132 (6 self)
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New emerging distributed multimedia applications provide guaranteed endtoend quality of service (QoS) and have stringent constraints on delay, delayjitter, cost, etc. The task of QoS routing is to find a route in the network which has sufficient resources to satisfy the constraints. The delaycost constrained routing problem is NPcomplete. We propose a heuristic algorithm for this problem. The idea is to first reduce the NPcomplete problem to a simpler one which can be solved in polynomial time, and then solve the new problem by either an extended Dijkstra's algorithm or an extended BellmanFord algorithm. We prove the correctness of our algorithm by showing that a solution for the simpler problem must also be a solution for the original problem. The performance of the algorithm is studied by both theoretical analysis and simulation. 1 Introduction Quality of Service (QoS) routing has been attracting considerable attention in the research community recently [6, 10, 11, 12, 13]. T...
Heuristic algorithms for multiconstrained qualityofservice routing
 Michigan State University, Michigan, in
, 2002
"... Multi–constrained Quality of Service (QoS) routing finds a route in the network that satisfies multiple independent quality of service constraints. This problem is NP–hard and a number of heuristic algorithms have been proposed to solve the problem. This paper studies two heuristics, the limited gra ..."
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Cited by 76 (2 self)
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Multi–constrained Quality of Service (QoS) routing finds a route in the network that satisfies multiple independent quality of service constraints. This problem is NP–hard and a number of heuristic algorithms have been proposed to solve the problem. This paper studies two heuristics, the limited granularity heuristic and the limited path heuristic, for solving general –constrained problems. Analytical and simulation studies are conducted to compare the time/space requirements of the heuristics and the effectiveness of the heuristics in finding the paths that satisfy the QoS constraints. We prove analytically that for an nodes and edges network with (a small constant) independent QoS constraints, the limited granularity heuristic must maintain a table of size in each node to be effective, which results in a time complexity of. We also prove that the limited path heuristic can achieve very high performance by maintaining entries in each node, which indicates that the performance of the limited path heuristic is not sensitive to the number of constraints. We conclude that although both the limited granularity heuristic and the limited path heuristic can efficiently solve –constrained QoS routing problems, the limited path heuristic is superior to the limited granularity heuristic in solving –constrained QoS routing problems "!$ # when. Our simulation study further confirms this conclusion. 1
MultiConstrained Optimal Path Selection
, 2001
"... Providing qualityofservice (QoS) guarantees in packet networks gives rise to several challenging issues. One of them is how to determine a feasible path that satisfies a set of constraints while maintaining high utilization of network resources. The latter objective implies the need to impose an a ..."
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Cited by 76 (1 self)
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Providing qualityofservice (QoS) guarantees in packet networks gives rise to several challenging issues. One of them is how to determine a feasible path that satisfies a set of constraints while maintaining high utilization of network resources. The latter objective implies the need to impose an additional optimality requirement on the feasibility problem. This can be done through a primary cost function (e.g., administrative weight, hopcount) according to which the selected feasible path is optimal. In general, multiconstrained path selection, with or without optimization, is an NPcomplete problem that cannot be exactly solved in polynomial time. Heuristics and approximation algorithms with polynomialand pseudopolynomialtime complexities are often used to deal with this problem. However, existing solutions suffer either from excessive computational complexities that cannot be used for online network operation or from low performance. Moreover, they only deal with special cases of the problem (e.g., two constraints without optimization, one constraint with optimization, etc.). For the feasibility problem under multiple constraints, some researchers have recently proposed a nonlinear cost function whose minimization provides a continuous spectrum of solutions ranging from a generalized linear approximation (GLA) to an asymptotically exact solution. In this paper, we propose an efficient heuristic algorithm for the most general form of the problem. We first formalize the theoretical properties of the above nonlinear cost function. We then introduce our heuristic algorithm (H MCOP), which attempts to minimize both the nonlinear cost function (for the feasibility part) and the primary cost function (for the optimality part). We prove that H MCOP guarantees at least t...
Distributed QoS Routing with Imprecise State Information
"... The goal of QualityofService (QoS) routing is to find a network path which has sufficient resources to satisfy certain constraints on metrics such as delay and bandwidth. The state information maintained at every node is often imprecise in a dynamic network because of nonnegligible propagation d ..."
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Cited by 65 (7 self)
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The goal of QualityofService (QoS) routing is to find a network path which has sufficient resources to satisfy certain constraints on metrics such as delay and bandwidth. The state information maintained at every node is often imprecise in a dynamic network because of nonnegligible propagation delay of state messages, periodic updates due to overhead concern, and hierarchical state aggregation. The information imprecision makes QoS routing difficult. The traditional shortestpath routing algorithm does not provide satisfactory performance when the state information is imprecise, and the flooding algorithm has an excessively high overhead. We propose a distributed routing scheme, called ticketbased probing, which searches multiple paths in parallel for a qualified one. The scheme is based on a realistic imprecision state model. The number of paths searched is determined in a flexible way, which allows the dynamic tradeoff between the overhead and the routing performance. The proposed routing algorithms collectively utilize the state information of the intermediate nodes to guide the routing messages along the most appropriate paths, so that the success probability is maximized with limited overhead. The algorithms consider not only the QoS requirement but also the optimality of the routing path. Lowcost paths are given preference in order to improve the overall network performance.
QualityofService Routing for Traffic with Performance Guarantees
 In Proc. IFIP International Workshop on Quality of Service
, 1997
"... QualityofService (QoS) routing tries to select a path that satisfies a set of QoS constraints, while also achieving overall network resource efficiency. We present initial results on QoS path selection for traffic requiring bandwidth and delay guarantees. For traffic with bandwidth guarantees, we ..."
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Cited by 57 (5 self)
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QualityofService (QoS) routing tries to select a path that satisfies a set of QoS constraints, while also achieving overall network resource efficiency. We present initial results on QoS path selection for traffic requiring bandwidth and delay guarantees. For traffic with bandwidth guarantees, we found that several routing algorithms that favor paths with fewer hops perform well. For traffic with delay guarantees, we show that for a broad class of WFQlike scheduling algorithms, the problem of finding a path satisfying bandwidth, delay, delayjitter, and/or buffer space constraints while at the same time deriving the bandwidth that has to be reserved to meet these constraints, is solvable by a modified version of the BellmanFord shortestpath algorithm in polynomial time.
A Survey of Combinatorial Optimization Problems in Multicast Routing
, 2003
"... In multicasting routing, the main objective is to send data from one or more source to multiple destinations, while at the same time minimizing the usage of resources. Examples of resources which can be minimized include bandwidth, time and connection costs. In this paper we survey applications of c ..."
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Cited by 40 (1 self)
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In multicasting routing, the main objective is to send data from one or more source to multiple destinations, while at the same time minimizing the usage of resources. Examples of resources which can be minimized include bandwidth, time and connection costs. In this paper we survey applications of combinatorial optimization to multicast routing. We discuss the most important problems considered in this area, as well as their models. Algorithms for each of the main problems are also presented.
Search Space Reduction in QoS Routing
 In Proceedings of the 19th International Conference on Distributed Computing Systems
, 2001
"... To provide realtime service or engineer constrainedbased paths, networks require the underlying routing algorithm to be able to find lowcost paths that satisfy given QualityofService (QoS) constraints. However, the problem of constrained... ..."
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Cited by 38 (3 self)
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To provide realtime service or engineer constrainedbased paths, networks require the underlying routing algorithm to be able to find lowcost paths that satisfy given QualityofService (QoS) constraints. However, the problem of constrained...
An Efficient Algorithm for Finding a Path Subject to Two Additive Constraints
 Computer Communications Journal
, 2000
"... One of the key issues in providing endtoend qualityofservice (QoS) guarantees in packet networks is how to determine a feasible route that satisfies a set of constraints. In general, finding a path subject to multiple additive constraints (e.g., delay, delayjitter) is an NPcomplete problem ..."
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Cited by 35 (5 self)
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One of the key issues in providing endtoend qualityofservice (QoS) guarantees in packet networks is how to determine a feasible route that satisfies a set of constraints. In general, finding a path subject to multiple additive constraints (e.g., delay, delayjitter) is an NPcomplete problem that cannot be exactly solved in polynomial time. Accordingly, several heuristics and approximation algorithms have been proposed for this problem. Many of these algorithms suffer from either excessive computational cost or low performance. In this paper, we provide an efficient approximation algorithm for finding a path subject to two additive constraints. The worstcase computational complexity of this algorithm is within a logarithmic number of calls to Dijkstra's shortest path algorithm. Its average complexity is even much lower than that, as demonstrated by simulation experiments. The performance of the proposed algorithm is justified via theoretical bounds that are provided for ...
Alternate Path Routing for Multicast
, 2000
"... Alternate path routing has been wellexplored in telecommunication networks as a means of decreasing the call blocking rate and increasing network utility. However, aside from some work applying these concepts to unicast flows, alternate path routing has received little attention in the Internet com ..."
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Cited by 31 (0 self)
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Alternate path routing has been wellexplored in telecommunication networks as a means of decreasing the call blocking rate and increasing network utility. However, aside from some work applying these concepts to unicast flows, alternate path routing has received little attention in the Internet community. We describe and evaluate an architecture for alternate path routing for multicast flows. For path installation, we design a receiveroriented alternate path protocol and prove that it reconfigures multicast trees without introducing loops. For path computation, we propose a scalable local search heuristic that allows receivers to find alternate paths using only partial network information. We use a simulation study to demonstrate the ability of local search to find alternate paths approximately as well as a linkstate protocol, with much lower overhead. I.