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Resource efficiency and survivability are critical concerns in elastic optical networks (EONs) with virtualization. In this paper, we investigate some important aspects in network survivability design against single-link failure under dedicated protection and bandwidth squeezing schemes when multiple virtual topologies are employed. We propose a link-path integer linear programming (ILP) formulation to solve the joint virtualization and survivability problem in elastic optical networks for large network instances, and derive some different types of protection for each virtual topology considering a channel-based spectrum approach to solve the spectrum allocation. Besides, we propose a heuristic to find a pair of predefined paths to ILP formulation aiming to minimize the link load. The proposed ILP and heuristic provide effective survivability solutions and spectrum resource savings for a cooperative design of modern survivable virtualized EONs taking advantages of a link-path model.

Leading state-of-the-art research facilities at the Universities of Edinburgh (UoE), Bristol (UoB), Lancaster (UoLan), King’s College London (KCL) and Digital Catapult (DCAT) are interconnected through a dedicated JISC/JANET network infrastructure. Using Software Defined Networking (SDN) and Network Function Virtualisation (NFV) technologies, these distributed test-beds are integrated using a multi-domain NFV Orchestrator. This paper introduces a novel specialist distributed test-bed developed for facilitating the increasingly large and complex experimentation of future Internet system architectures, technologies, services and applications between the geographically dispersed laboratories across the UK. The aim is to enable students, researchers and enterprises to interconnect with and carry out remote experiments using these test-beds. Each one contributes a range of key capabilities for Internet research including optical networks, optical wireless and radio frequency communications, Internet of Things (IoT), SDN, NFV, as well as cloud computing technologies and services.

The adoption of software defined networking (SDN) within traditional networks has provided operators the ability to manage diverse resources and easily reconfigure networks as requirements change. Recent research has extended this concept to IEEE 802.15.4 low-power wireless networks, which form a key component of the Internet of Things (IoT). However, the multiple traffic patterns necessary for SDN control makes it difficult to apply this approach to these highly challenging environments. This paper presents Atomic-SDN, a highly reliable and low-latency solution for SDN in low-power wireless. Atomic-SDN introduces a novel synchronous flooding (SF) architecture capable of dynamically configuring SF protocols to satisfy complex SDN control requirements, and draws from the authors' previous experiences in the IEEE EWSN Dependability Competition: where SF solutions have consistently outperformed other entries. Using this approach, Atomic-SDN presents considerable performance gains over other SDN implementations for low-power IoT networks. We evaluate the Atomic-SDN through simulation and experimentation, and show how utilizing SF techniques provides latency and reliability guarantees to SDN control operations as the local mesh scales. We compare the Atomic-SDN against the other SDN implementations based on the IEEE 802.15.4 network stack, and establish that the Atomic-SDN improves SDN control by orders-of-magnitude across latency, reliability and energy-efficiency metrics.

Along with the adoption of 5G, the development of neutral host solutions provides a unique opportunity for mobile networks operators to accommodate the needs of emerging use-cases and in the consolidation of new business models. By exploiting the concept of network slicing, as one key enabler in the transition to 5G, infrastructure and service providers can logically split a shared physical network into multiple isolated and customized networks to flexibly address the specific demands of those tenant slices. Motivated by this reality, the H2020 5GCity project proposed a novel 5G-enabled neutral host framework for three European cities: Barcelona (ESP), Bristol (UK), and Lucca (IT). This article revises the main achievements and contributions of the 5GCity project, focusing on the deployment and validation of the proposed framework. The developed neutral host framework encompasses two main parts: the infrastructure and the software platform. A detailed description of the framework implementation, in terms of functional capabilities and practical implications of city-wide deployments, is provided in this article. This work also presents the performance evaluation of the proposed solution during the implementation of real vertical use cases. Obtained results validate the feasibility of the neutral host model and the proposed framework to be deployed in city-wide 5G infrastructures.

The time shared optical network (TSON) has been proposed as a dynamic optical transport network solution to provide high bandwidth and low latency connectivity in support of 5G technology and beyond. This work reviews the TSON evolution stages developed in the framework of the U.K. national project Towards Ultimate Convergence of All Networks (TOUCAN). The details of the TSON architecture and its various development phases are discussed, and the performance of its latest implementation is evaluated through relevant demonstration activities across the Smart Internet Lab’s 5G (5GUK) test network.

Objective: To detect common chromosomal aneuploidy variations in embryos from couples undergoing assisted reproductive technology and preimplantation genetic screening and their possible associations with embryo quality. Methods: In this study, 359 embryos from 62 couples were screened for chromosomes 13, 21, 18, X, and Y by fluorescence insitu hybridization. For biopsy of blastomere, a laser was used to remove a significantly smaller portion of the zona pellucida. One blastomere was gently biopsied by an aspiration pipette through the hole. After biopsy, the embryo was immediately returned to the embryo scope until transfer. Embryo integrity and blastocyst formation were assessed on day 5. Results: Totally, 282 embryos from 62 couples were evaluated. The chromosomes were normal in 199 (70.57%) embryos and abnormal in 83 (29.43%) embryos. There was no significant association between the quality of embryos and numerical chromosomal abnormality (P=0.67). Conclusions: Embryo quality is not significantly correlated with its genetic status. Hence, the quality of embryos determined by morphological parameters is not an appropriate method for choosing embryos without these abnormalities.