The British Telecom microwave network was a network of point-to-point microwave radio links in the United Kingdom, operated at first by the General Post Office, and subsequently by its successor BT plc. From the late 1950s to the 1980s it provided a large part of BT's trunk communications capacity, and carried telephone, television and radar signals and digital data, both civil and military. Its use of line-of-sight microwave transmission was particularly important during the Cold War for its resilience against nuclear attack. It was rendered obsolete, at least for normal civilian purposes, by the installation of a national optical fibre communication network with considerably higher reliability and vastly greater capacity.BT remains one of the largest owners of transmission and microwave towers in the UK. The most famous of these is the BT Tower in London, which was the tallest building in the UK from its construction in the 1960s until the early 1980s, and a major node in the BT microwave network. Wikipedia.
Aweya J.,British Telecom
IEEE Communications Surveys and Tutorials | Year: 2014
Network infrastructures are gradually migrating from time-division multiplexing (TDM) based onto packet-based architectures. In spite of this convergence, there are a significant number of synchronous applications that require accurate timing to be distributed over the packet networks. Examples of precision timing sensitive applications that need the transport of synchronization over packet networks include interconnection and transport of TDM services over packet networks (TDM switches, TDM PBXs, voice, video-conferencing and broadband video), and connections to 2G, 3G, and 4G wireless base stations. TDM networks, unlike packet networks (e.g., Ethernet, IP, MPLS), have timing transfer inherently built into them. Native Ethernet (IEEE 802.3) is inherently asynchronous and was not designed with timing transfer in mind. Synchronous Ethernet (Sync-E), defined by the ITU-T, has emerged as a powerful, yet simple technology, for accurate timing transfer over Ethernet networks using quotedblleft TDM-likequotedblright (precisely, SDH/SONET) timing techniques. This discussion explains what Sync-E is, followed by a detailed discussion on which flavors of Ethernet can support Sync-E and which cannot. The discussion includes how Sync-E can be implemented in the popular Ethernet versions. We then describe example Sync-E node timing architectures, and some network timing applications and related issues. © 2014 IEEE.
Achilleos A.,University of Essex |
Yang K.,University of Essex |
Georgalas N.,British Telecom
Pervasive and Mobile Computing | Year: 2010
Pervasive service creation entails a complex process that involves a diversity of development aspects. Context-awareness is an important facet of pervasive service creation, which deals with the acquisition, rendering, representation and utilisation of context information. In this paper we tackle context-awareness at the application level dealing with the representation and utilisation of context by services. We propose a model-driven approach that facilitates the creation of a context modelling framework and simplifies the design and implementation of pervasive services. To conclude, we demonstrate the benefits of our model-driven approach via the creation of a pervasive museum service and its evaluation using selected software metrics. © 2010.
Hawilo H.,University of Western States |
Shami A.,University of Western States |
Mirahmadi M.,IBM |
Asal R.,British Telecom
IEEE Network | Year: 2014
As mobile network users look forward to the connectivity speeds of 5G networks, service providers are facing challenges in complying with connectivity demands without substantial financial investments. Network function virtualization (NFV) is introduced as a new methodology that offers a way out of this bottleneck. NFV is poised to change the core structure of telecommunications infrastructure to be more cost-efficient. In this article, we introduce an NFV framework, and discuss the challenges and requirements of its use in mobile networks. In particular, an NFV framework in the virtual environment is proposed. Moreover, in order to reduce signaling traffic and achieve better performance, this article proposes a criterion to bundle multiple functions of a virtualized evolved packet core in a single physical device or a group of adjacent devices. The analysis shows that the proposed grouping can reduce the network control traffic by 70 percent. © 1986-2012 IEEE.
Leonhardt P.,British Telecom
Journal of Telecommunications and Information Technology | Year: 2013
The London 2012 Olympic and Paraolympic Games drew together tens of thousands of people in the form of athletes, organisers, media, VIPs, public and many more groups and individuals. With the growth in smart phones and tablets coupled with the ever expanding volume and range of content accessed via Aps and browsers, this huge volume of people expected connectivity from their mobile devices during their time on the Olympic sites. It was BT's role in the games as the official communications services partner to deliver Wi-Fi connectivity across the venues, covering the range of users from the public, athletes, organisers and ticket scanners. This paper examines this state of the art Wi-Fi solution.
Ruta D.,British Telecom |
Gabrys B.,Bournemouth University |
Lemke C.,Bournemouth University
IEEE Transactions on Knowledge and Data Engineering | Year: 2011
Rapidly evolving businesses generate massive amounts of time-stamped data sequences and cause a demand for both univariate and multivariate time series forecasting. For such data, traditional predictive models based on autoregression are often not sufficient to capture complex nonlinear relationships between multidimensional features and the time series outputs. In order to exploit these relationships for improved time series forecasting while also better dealing with a wider variety of prediction scenarios, a forecasting system requires a flexible and generic architecture to accommodate and tune various individual predictors as well as combination methods. In reply to this challenge, an architecture for combined, multilevel time series prediction is proposed, which is suitable for many different universal regressors and combination methods. The key strength of this architecture is its ability to build a diversified ensemble of individual predictors that form an input to a multilevel selection and fusion process before the final optimized output is obtained. Excellent generalization ability is achieved due to the highly boosted complementarity of individual models further enforced through cross-validation-linked training on exclusive data subsets and ensemble output postprocessing. In a sample configuration with basic neural network predictors and a mean combiner, the proposed system has been evaluated in different scenarios and showed a clear prediction performance gain. © 2006 IEEE.