5,538 research outputs found
Optical Network Virtualisation using Multi-technology Monitoring and SDN-enabled Optical Transceiver
We introduce the real-time multi-technology transport layer monitoring to
facilitate the coordinated virtualisation of optical and Ethernet networks
supported by optical virtualise-able transceivers (V-BVT). A monitoring and
network resource configuration scheme is proposed to include the hardware
monitoring in both Ethernet and Optical layers. The scheme depicts the data and
control interactions among multiple network layers under the software defined
network (SDN) background, as well as the application that analyses the
monitored data obtained from the database. We also present a re-configuration
algorithm to adaptively modify the composition of virtual optical networks
based on two criteria. The proposed monitoring scheme is experimentally
demonstrated with OpenFlow (OF) extensions for a holistic (re-)configuration
across both layers in Ethernet switches and V-BVTs
Low energy indoor network : deployment optimisation
This article considers what the minimum energy indoor access point deployment is in order to achieve a certain downlink quality-of-service. The article investigates two conventional multiple-access technologies, namely: LTE-femtocells and 802.11n Wi-Fi. This is done in a dynamic multi-user and multi-cell interference network. Our baseline results are reinforced by novel theoretical expressions. Furthermore, the work underlines the importance of considering optimisation when accounting for the capacity saturation of realistic modulation and coding schemes. The results in this article show that optimising the location of access points both within a building and within the individual rooms is critical to minimise the energy consumption
A survey of self organisation in future cellular networks
This article surveys the literature over the period of the last decade on the emerging field of self organisation as applied to wireless cellular communication networks. Self organisation has been extensively studied and applied in adhoc networks, wireless sensor networks and autonomic computer networks; however in the context of wireless cellular networks, this is the first attempt to put in perspective the various efforts in form of a tutorial/survey. We provide a comprehensive survey of the existing literature, projects and standards in self organising cellular networks. Additionally, we also aim to present a clear understanding of this active research area, identifying a clear taxonomy and guidelines for design of self organising mechanisms. We compare strength and weakness of existing solutions and highlight the key research areas for further development. This paper serves as a guide and a starting point for anyone willing to delve into research on self organisation in wireless cellular communication networks
An anycast based feedback aggregation scheme for efficient network transparency in cross-layer design
To ensure Quality of Service for multimedia data sessions in next generation mobile telecommunication systems, jointly-optimized cross-layer architectures were introduced recently. Such shemes usually require an adaptive media source which is able to modify the main parameters of ongoing connections by transferring control and feedback information via the network and through different protocol layers from application layer to physical layer and vice versa, according to the actual state of the path between peer nodes. This concept of transmitting cross-layer information is referred as network transparency in the literature, meaning that the underlying infrastructure is almost invisible to all the entities involved in joint optimization due to the continuous conveyance of cross-layer feedbacks. In this paper we introduce and evaluate a possible solution for reducing the network overhead caused by this volume of information exchange. Our soulution is based on the anycasting communication paradigm and creates a hierarchical data aggregation scheme allowing to adapt each entity of the multimedia transmission chain based on frequent feedbacks and even so in a low-bandwitdh manner
Project FATIMA Final Report: Part 1.
EXECUTIVE SUMMARY
This Final Report covers the results of the EU-funded research project FATIMA (Financial Assistance for Transport Integration in Metropolitan Areas) which had the following objectives:
(i) to identify the benefits to the private sector of optimal urban transport strategies, and the potential for obtaining private sector funding to reflect those benefits;
(ii) to determine the differences between strategies optimised using public funds and those optimised within the constraints imposed by private funding initiatives;
(iii) to propose mechanisms by which private sector funding can be provided so as to achieve appropriately optimal transport strategies while maintaining quality of operation; and
(iv) to use the results to provide more general guidance on the role of private sector funding for urban transport in the EU.
The project adopted an approach which involved the application of the same study method to nine cities, chosen to reflect a range of urban transport policy contexts in Europe: Edinburgh, Eisenstadt, Helsinki, Merseyside, Oslo, Salerno, Torino, Tromsø and Vienna. This method involved specifying appropriate policy objective functions against which transport strategies could be assessed, and finding the specific strategy that optimised each of these functions. The objective functions covered a range of differing regimes with respect to constraints on public finance and the involvement of the private sector.
It was found that, in a majority of the case study cities, optimal socio-economic policies could be funded by road pricing or increased parking charges, considered over a 30 year time horizon. Such measures would typically be used to make it feasible to increase public transport frequency levels or decrease public transport fares. In general it was found to be important that the city transport planning authority had complete control over all transport measures, affecting both private and public transport.
However, such strategies are likely to require significant levels of investment and, given current attitudes towards constraints on public spending, it might be politically awkward for the public sector to raise such finance. There is thus a potentially useful role for private finance to be used to help overcome such (short term) financing problems. However, it must be appreciated that the private sector will expect to make a profit on such investment. In cities where optimal policies are funded by travellers, the private sector can be reimbursed by travellers. In cities where it is unfeasible for travellers to fund all the costs of optimal policies, it will be necessary for the private sector to be reimbursed from public funds (raised from taxes). An important issue here is that the use of private finance should not be allowed to replace optimal policies with sub-optimal policies.
Whether or not the private sector is involved in financing a strategy, there may be interest in private sector operation of the public transport service. However, evidence on the scale of benefits or losses from such operation is unclear. If, though, a city authority decides that private operation is beneficial, it should use, where legally possible, a franchising model in which it specifies optimal public transport service levels and fares. On the other hand, if a deregulation model is required (in order to comply with national law), private operators should not be given complete freedom to determine the operating conditions which meet their profitability target, even if the level of profitability is itself constrained as a result. There are typically a number of combinations (e.g. of fares and frequency) which achieve a given level of profitability, and not all will be equally effective in terms of public policy objectives
Business Case and Technology Analysis for 5G Low Latency Applications
A large number of new consumer and industrial applications are likely to
change the classic operator's business models and provide a wide range of new
markets to enter. This article analyses the most relevant 5G use cases that
require ultra-low latency, from both technical and business perspectives. Low
latency services pose challenging requirements to the network, and to fulfill
them operators need to invest in costly changes in their network. In this
sense, it is not clear whether such investments are going to be amortized with
these new business models. In light of this, specific applications and
requirements are described and the potential market benefits for operators are
analysed. Conclusions show that operators have clear opportunities to add value
and position themselves strongly with the increasing number of services to be
provided by 5G.Comment: 18 pages, 5 figure
- …