Andreas Fischer

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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(More)
Waste of energy due to over-provisioning and over-dimensioning of network infrastructures has recently stimulated the interest on energy consumption reduction by Internet Service Providers (ISPs). By means of resource consolidation, network virtualization based architectures will enable energy saving. In this letter, we extend the well-known virtual network(More)
It is widely accepted that the network of the future will require a greater degree of service awareness and optimal use of network resources. This article presents an architectural design for an open software-defined network infrastructure that enables the composition of fast and guaranteed services in an efficient manner and the execution of these services(More)
Network virtualization is recognized as an enabling technology for the Future Internet. Applying virtualization of network resources leads to the problem of mapping virtual resources to physical resources, known as “Virtual Network Embedding” (VNE). Several algorithms attempting to solve this problem have been discussed in the literature, so far. However,(More)
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(More)
The resilience of services in the Internet has become an important issue and is expected to become even more important in the future. Virtualization is one of the means which can be deployed for resilience purposes. In this paper we follow a systematic approach to the use of virtualization to increase the resilience of network services. First, we provide an(More)
Network Virtualization is recognized as a key technology for the Future Internet. Energy-efficiency is one of the main challenges in future networking environments. Most algorithms for mapping virtual resources to substrate resources however do not consider energy as a factor for the mapping. In order to evaluate the energy-efficiency of such a mapping, an(More)
Network virtualization is seen as an enabling technology for the Future Internet. In this context, many Virtual Network Embedding algorithms have been introduced in literature so far. This paper discusses an open source framework for the evaluation of such algorithms. The paper describes features provided by the framework, how to use the framework for(More)
One of the main challenges of network virtualization is the mapping of virtual network demands to physical network resources, commonly known as the virtual network embedding (VNE) problem. This paper introduces DPVNE, a distributed, parallel and generic VNE framework. DPVNE can be used 1) to run various cost-reducing embedding algorithms 2) in a distributed(More)