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Virtual network (VN) mapping which deals with the allocation of network resources from the shared physical substrate to individual VNs is one of the key challenges for the application of realizing network virtualization. While a v...
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Virtual network (VN) mapping which deals with the allocation of network resources from the shared physical substrate to individual VNs is one of the key challenges for the application of realizing network virtualization. While a variety of state-of-the-art algorithms have attempted to address this issue from different aspects, the challenge still remains for mapping virtual link with hop count constraint. This paper presents a fast approximation path mapping algorithm to address this issue by formulating such virtual link mapping problem as a path-flow mathematical programming model, which aims to minimize the maximum link load factor. Through the use of the primal-dual method, a fully polynomial time approximation algorithm is proposed to solve this model. The experimental results show that the proposed algorithm can effectively solve the problem of path mapping with hop limit.
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Network virtualization is a promising solution that can prevent network ossification by allowing multiple heterogeneous virtual networks (VNs) to cohabit on a shared substrate network. It provides flexibility and promotes diversit...
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Network virtualization is a promising solution that can prevent network ossification by allowing multiple heterogeneous virtual networks (VNs) to cohabit on a shared substrate network. It provides flexibility and promotes diversity. A key issue that needs to be addressed in network virtualization is allocation of substrate resources for the VNs with respect to their resource requirements and the topologies of the substrate and virtual networks, namely the VN mapping (VNM) problem. Efficient VNM algorithms aim to maximize the number of coexisting VNs, and increase the utilization and revenue obtained from the substrate resources. In this paper, we present an online VNM algorithm (OVNM) that maximizes the number of coexisting VNs leading to good utilization and revenue of the substrate. Using the OVNM algorithm, we estimate the VN mapping and evaluate the associated substrate resources to map the VN within a proper region on the substrate by using the FVN_Sort (first virtual node sorting) function. This improves the probability of a VN mapping success. Furthermore, by mapping the virtual nodes and links in a coordinated fashion, the resource consumption while mapping is minimized. We evaluate the performance of our approach by using simulation, and show that the algorithm has an acceptable run time and leads to a better blocking probability performance, which means more coexisting VNs.
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Network virtualization has been proposed as a technology that aims to solve the Internet ossification. Central to the network virtualization is a virtual network composition mechanism providing an efficient mapping of virtual node...
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Network virtualization has been proposed as a technology that aims to solve the Internet ossification. Central to the network virtualization is a virtual network composition mechanism providing an efficient mapping of virtual nodes and links onto appropriate physical resources in the network infrastructure. This paper proposes a novel backtracking heuristic algorithm for virtual network composition. Based on this algorithm, two approaches with two different objectives are presented. The first approach (Backtracking-CR) aims to compose a virtual network using the least amount of network resources, while the second (Backtracking-LB) applies load balancing for virtual network composition. Furthermore, a linear programming approach that optimizes the virtual network composition with an objective of using the least amount of network resources is presented and used to bench mark the heuristic algorithm. Simulation results show that using less network resources by applying linear programming or Backtracking-CR does not produce higher number of successfully mapped virtual networks when is compared to load balancing approach. Results also show that the proposed heuristic algorithm is scalable to large physical and virtual networks with respect to the computation time.
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Network virtualization is a way to simultaneously run multiple heterogeneous architectures on a shared substrate. The main issue in network virtualization is mapping virtual networks to substrate network. How to manage substrate r...
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Network virtualization is a way to simultaneously run multiple heterogeneous architectures on a shared substrate. The main issue in network virtualization is mapping virtual networks to substrate network. How to manage substrate resources in mapping phase will have an effective role in improving the use of infrastructure resources. Using software-based networks in network virtualization which separates control logic from data as a new technology, has led to efficient resource management in this context. In this article a software-based network approach has been presented to network virtualization and manage infrastructure resources efficiently. It optimizes mapping function by dynamic resource management of infrastructure resource. We have added a module in the controller to manage the resources dynamically. An initial mapping will be done for arriving new requests based on number of successful requests and arriving time slots. They will not be finalized by writing the rules in the switches before arriving n requests. If some remapping during the n time window is needed, remapping can be done by the controller and the final results are sent to the switches to write the flow rules. The simulation has been done using NS2 simulator showed based on different evaluation criteria such as acceptance rate, average link utilization, cost and delay.
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Network virtualization is recognized as an enabling technology for the future Internet. It aims to overcome the resistance of the current Internet to architectural change. Application of this technology relies on algorithms that c...
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Network virtualization is recognized as an enabling technology for the future Internet. It aims to overcome the resistance of the current Internet to architectural change. Application of this technology relies on algorithms that can instantiate virtualized networks on a substrate infrastructure, optimizing the layout for service-relevant metrics. This class of algorithms is commonly known as "Virtual Network Embedding (VNE)" algorithms. This paper presents a survey of current research in the VNE area. Based upon a novel classification scheme for VNE algorithms a taxonomy of current approaches to the VNE problem is provided and opportunities for further research are discussed.
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Network virtualization is a key provision for improving the scalability and reliability of cloud computing services. In recent years, various mapping schemes have been developed to reserve VN resources over substrate networks. How...
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Network virtualization is a key provision for improving the scalability and reliability of cloud computing services. In recent years, various mapping schemes have been developed to reserve VN resources over substrate networks. However, many cloud providers are very concerned about improving service reliability under catastrophic disaster conditions yielding multiple system failures. To address this challenge, this work presents a novel failure region-disjoint VN mapping scheme to improve VN mapping survivability. The problem is first formulated as a mixed integer linear programming problem and then two heuristic solutions are proposed to compute a pair of failure region-disjoint VN mappings. The solution also takes into account mapping costs and load balancing concerns to help improve resource efficiencies. The schemes are then analyzed in detail for a variety of networks and their overall performances compared to some existing survivable VN mapping schemes.
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Network virtualization has emerged as a solution for the Internet inability to address the required challenges caused by the lack of coordination among Internet service providers for the deployment of new services. The allocation ...
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Network virtualization has emerged as a solution for the Internet inability to address the required challenges caused by the lack of coordination among Internet service providers for the deployment of new services. The allocation of resources is one of the main problems in network virtualization, mainly in the mapping of virtual nodes and links to specific substrate nodes and paths, also known as the virtual network embedding problem. This paper proposes an algorithm based on optimization theory, to map the virtual links and nodes requiring a specific demand, looking for the maximization of the spare bandwidth and spare CPU in the substrate network, taking into account the CPU demanded by the hidden hops when a virtual link is mapped. The components of the virtual networks (nodes and links) that do not ask for an specific demand are then allocated following a fairness criteria.
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摘要 :
Network virtualization has emerged as a solution for the Internet inability to address the required challenges caused by the lack of coordination among Internet service providers for the deployment of new services. The allocation ...
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Network virtualization has emerged as a solution for the Internet inability to address the required challenges caused by the lack of coordination among Internet service providers for the deployment of new services. The allocation of resources is one of the main problems in network virtualization, mainly in the mapping of virtual nodes and links to specific substrate nodes and paths, also known as the virtual network embedding problem. This paper proposes an algorithm based on optimization theory, to map the virtual links and nodes requiring a specific demand, looking for the maximization of the spare bandwidth and spare CPU in the substrate network, taking into account the CPU demanded by the hidden hops when a virtual link is mapped. The components of the virtual networks (nodes and links) that do not ask for an specific demand are then allocated following a fairness criteria.
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In virtual network (VN) embedding problem, researchers usually assume VN requests to be permanent. However, VN requests evolve frequently in practice. In this paper, we focus on re-embedding process after VN requests evolve, and p...
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In virtual network (VN) embedding problem, researchers usually assume VN requests to be permanent. However, VN requests evolve frequently in practice. In this paper, we focus on re-embedding process after VN requests evolve, and propose an incremental re-embedding scheme which tries to reduce the number of virtual nodes that need to be re-embedded. Simulation results show that our scheme achieves better performance in three performance metrics, compared with three baseline schemes.
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Network virtualization facilitates the technology advancement via decoupling the traditional Internet Service Providers (ISPs) into the infrastructure provider (InP) and the service provider (SP). Revolutionary technologies hence ...
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Network virtualization facilitates the technology advancement via decoupling the traditional Internet Service Providers (ISPs) into the infrastructure provider (InP) and the service provider (SP). Revolutionary technologies hence can be easily employed by the SP and transparently mapped to the physical network managed by the InP after resolving the network embedding problem. In this work, we target on importing resilience to the virtualization context by solving the survivable network embedding (SNE) problem. We view the SNE problem from a multi-commodity network flow perspective, and present an Integer Linear Programming (ILP) model for both splittable and non-splittable flow to achieve joint optimal allocation for the working and backup resources. For large-scale problems, we propose two efficient heuristic algorithms for the case with splittable and non-splittable flow, respectively. Our performance evaluation shows that the splittable mapping outperforms the non-splittable mapping in terms of the consumed resources, while the latter bears the advantage of consistent QoS guarantee.
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