Klaus D. Hackbarth

An Economical Cost Model for Fair Resource Sharing in Virtual Home Environments

Home networks recently gain importance due to their development from pure internal networks in form of an Ethernet LAN to converged networks integrating home, Internet, and access provider infrastructure. In emerging future home networking scenarios, service provisioning and network management is proposed by distributed architectures forming virtual home environments (VHEs). This paper provides a service description and corresponding traffic and cost model for fair resource sharing in VHEs. The objective of the proposed cost model is to allow an evaluation of the contribution and consumption for each user participating in the VHE to find an economic balance in the distributed behavior. Hereby, the contribution counts positively and the consumption negatively. The economic balance controls the load balancing in the VHE and further limits the consumption of resources for users which over-pass a corresponding threshold of negative balance leading to an exclusion from the VHE, if the negative balance is not equilibrated over a mean- or long-time horizon.

Cost models for QoS-differentiated interconnecting and wholesale access services in future generation networks

Currently, network operators and Internet service providers are offering “Triple Play” products integrating services with different Quality of Service (QoS) requirements. It is leading to Internet traffic with strong service integration under an all-IP-based broadband network platform. However, new multimedia service offers require individual QoS guarantees for each type of services. The interconnection between different providers necessitates the reconsideration of the actual cost schemes. Interconnection and wholesale access services (It is an extension of “wholesale network” definition, where Telco’s physical network and equipment are “shared” to many independent Service Providers. If the incumbent offers broadband access services, the rest of the alternative providers have recourse to the incumbent’s “wholesale access service”. Bitstream service is the most important service of this type, actually regulated over DSL and cable networks.) appear to be a simple solution, but the consideration of QoS parameters requires an extension of the current network dimensioning methods based mainly on the average bandwidth demand from each user. This paper proposes a cost model which considers QoS parameters and, based on the “Total Element based Long Run Incremental Cost” (TELRIC) model, is applied to the wholesale access and interconnection paradigm. Three traffic engineering methods are considered and studied for network dimensioning. Hereby the aim is to guarantee the QoS of the different services: complete traffic segregation under virtual tunnels, complete traffic integration by over-engineering and partial traffic integration using a priority queuing scheme. The proposed method enables the development of a specific cost scheme based on a complete scenario considering different types of users. The variety of used IP applications suppose direct implications over different levels of interconnection, mainly at the low-level Metro access and the high-level edge node.

Quality of experience

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Novel heuristics for cell radius determination in WCDMA systems and their application to strategic planning studies

We propose and compare three novel heuristics for the calculation of the optimal cell radius in mobile networks based on Wideband Code Division Multiple Access (WCDMA) technology. The proposed heuristics solve the problem of the load assignment and cellular radius calculation. We have tested our approaches with experiments in multiservices scenarios showing that the proposed heuristics maximize the cell radius, providing the optimum load factor assignment. The main application of these algorithms is strategic planning studies, where an estimation of the number of Nodes B of the mobile operator, at a national level, is required for economic analysis. In this case due to the large number of different scenarios considered (cities, towns, and open areas) other methods than simulation need to be considered. As far as we know, there is no other similar method in the literature and therefore these heuristics may represent a novelty in strategic network planning studies. The proposed heuristics are implemented in a strategic planning software tool and an example of their application for a case in Spain is presented. The proposed heuristics are used for telecommunications regulatory studies in several countries.

Application of cost models over traffic dimensioning with QoS restrictions

Network operators and Internet service providers are offering “Triple Play” products integrating services with different quality of service (QoS) requirements. The provision of QoS guarantees implies the revision of current dimensioning methods and consequences for costing and pricing. This paper proposes a cost model which considers QoS parameters, based on the Total Element Long Run Incremental Cost (TELRIC) model, calculating the cost of a network element and distributing it over the different services whose traffic uses it, taking into account the QoS requirements of each service. For this purpose, three traffic engineering methods are analyzed: complete traffic aggregation by “Over-engineering,” complete traffic segregation by separated virtual tunnels, and partial traffic aggregation by priority queuing. As an example, the cost model is applied to the connection in a Next Generation Network aggregation network for estimating the influence of QoS and traffic engineering on the cost estimation under the TELRIC model.

Cost models for Next Generation Networks with Quality of Service parameters

Most network operators and Internet service providers are offering Triple Play products that integrate services with different QoS requirements. A correct tariff scheme for these products should be correlated with the cost of production. This paper proposes a model based on TELRIC to calculate and distribute the cost of a network element according to the usage that each user type makes of it, based on the services demanded by the user. The cost model is based on the QoS required by different types of service and three traffic engineering methods: over-engineering, separated virtual tunnels and priority queuing, and studies their influence in costing estimation. The cost model is applied as an example to a connection between a DSLAM and a concentrator in order to estimate the influence of the QoS and the traffic engineering mechanisms in the resulting cost.

Approximation towards energy-efficient distributed environments

Peer-To-Peer (P2P) traffic represents almost 60 % of Internet traffic, and involves personal computers working during periods of full-time operation (Always-ON). The rational use of shared resources opens up the possibility of reducing energy consumption associated with this type of operation. This paper analyses the results previously obtained from simulating an environment that shares resources among multimedia home networks, called Virtual Home Environment (VHE) and sponsored by the European Network of Excellence EuroFGI [1]. The study analyzes the behavior of basic P2P distributed environments, comparing them to the new environment based on the virtualization of specific processes. This proposal includes a cost model that enables the restriction of behaviors associated with hoarding of resources. As a result, the energy consumption associated with this improvement implies a substantial reduction in the number of Always-ON devices, and the reduction and equalization of activity time around the area of the distributed network. The proposed simulation will be applied in future developments related with the activities proposed by Cost Action IC0804: Energy efficiency in large-scale distributed systems, see [2].

DIDERO 3G A STRATEGIC NETWORK PLANNING TOOL FOR 3G MOBILE NETWORKS

Strategic Planning for mobile networks has to consider the evolution from the existing 2nd Generation GSM architecture to a long term 3rd Generation UMTS architecture over various intermediate steps in the form of hybrid networks. The study of this evolution requires a corresponding Strategic Planning tool. This article deals with Strategic Network Planning and develops the corresponding models considering aspects like radio propagation, multi-service traffic and user mobility. The article presents a corresponding strategic planning tool which allows to study the evolution of a mobile network under the corresponding input data in the form of a service and topographic scenarios. The application of the tool to a specific network region is shown and costing perspectives for the different services are discussed.

2G/3G-Connect: A Tool for Strategic Techno-Economical Studies on National-Wide Mobile Networks under a Hybrid 2G/3G Architecture

The current increment of the service portfolio for mobile communications and the related traffic load require an extension of the capacities in the mobile networks. As a consequence, mobile network operators have to replace part of the traditional equipment based on 2G GSM/GPRS by the 3G equipment based on UMTS and even start the path in direction to the 4G installing HSPA. This leads to techno-economical studies which require a corresponding service network model and its implementation in form of a computer support planning tool. This paper presents such a model and the structure and characteristics of the corresponding tool 2G/3G-Conncet. The paper also indicates corresponding applications.

Web-based service for remote execution: NGI network design application

A specific objective of the EURO-NGI network is the development of a Macro-tool which provides a homogeneous environment for hosting and interrelation of the software tools developed by the research labs of the network. The development of such a software environment raises several coordination and integration issues. This paper proposes tool integration under a common user access interface as an optimal solution and proposes the Web interface as the most natural option. The paper explains several innovative aspects in the field of remote software tool execution, secure access, customized interfaces and sharing environments for simultaneous execution and exposure of the main aspects of a sharing environment for network planning tools, named WeBaSeRex and its application for tasks in the EURO-NGI network of excellence.