Assessment of Karstification Degree in the Copacabana Group for a Tailings Dam Foundation, South Andes, Peru

The world-wide occurrence of carbonate rocks is extensive, and Peru is no exception. Many mining facilities are located in or on carbonate rocks. Under specific conditions, carbonate rocks show varying degrees of karstification, which represent a potential high risk of damage or failure to mine facilities, especially tailings and water impoundments due to subsidence or internal erosion problems. Adequate engineering measures, including proper characterization of the foundation materials, should be taken to characterize foundation materials and mitigate the risk. This paper presents the assessment of the potential of karst dissolution in the Copacabana Group underlying about 50% the foundation of a proposed tailings dam and storage facility, located in the South Andes of Peru. A thorough geotechnical site investigation program was carried out in the area, which included regional and local geological mapping, geotechnical drilling, test pits, permeability tests, effervescence test in cores, petrographic analyses, and X-Ray diffraction tests. Hydrogeological studies, such as pumping and tracer tests, were also performed by other consultants to verify the observations, conclusions, and opinions developed from the geotechnical investigation program. The results of the geotechnical investigation allowed proper characterization of the dam foundation and the tailings storage facility and estimation of the degree of karstification in the carbonate rocks of the Copacabana Group. The completed geological site characterization was then used to locate the tailings dam and impoundment area to avoid areas of pervasive karst and to implement defensive engineering measures, including grout curtains and slush grouting of smaller cavities and joints, among others

Software-Defined Networking: A Comprehensive Survey

peer reviewedThe Internet has led to the creation of a digital society, where (almost) everything is connected and is accessible from anywhere. However, despite their widespread adoption, traditional IP networks are complex and very hard to manage. It is both difficult to configure the network according to predefined policies, and to reconfigure it to respond to faults, load, and changes. To make matters even more difficult, current networks are also vertically integrated: the control and data planes are bundled together. Software-defined networking (SDN) is an emerging paradigm that promises to change this state of affairs, by breaking vertical integration, separating the network's control logic from the underlying routers and switches, promoting (logical) centralization of network control, and introducing the ability to program the network. The separation of concerns, introduced between the definition of network policies, their implementation in switching hardware, and the forwarding of traffic, is key to the desired flexibility: by breaking the network control problem into tractable pieces, SDN makes it easier to create and introduce new abstractions in networking, simplifying network management and facilitating network evolution. In this paper, we present a comprehensive survey on SDN. We start by introducing the motivation for SDN, explain its main concepts and how it differs from traditional networking, its roots, and the standardization activities regarding this novel paradigm. Next, we present the key building blocks of an SDN infrastructure using a bottom-up, layered approach. We provide an in-depth analysis of the hardware infrastructure, southbound and northbound application programming interfaces (APIs), network virtualization layers, network operating systems (SDN controllers), network programming languages, and network applications. We also look at cross-layer problems such as debugging and troubleshooting. In an effort to anticipate the future evolution of this - ew paradigm, we discuss the main ongoing research efforts and challenges of SDN. In particular, we address the design of switches and control platforms—with a focus on aspects such as resiliency, scalability, performance, security, and dependability—as well as new opportunities for carrier transport networks and cloud providers. Last but not least, we analyze the position of SDN as a key enabler of a software-defined environment

An integrated view on monitoring and compensation for dynamic optical networks: from management to physical layer

A vertical perspective, ranging from management and routing to physical layer options, concerning dynamic network monitoring and compensation of impairments (M&C), is given. Feasibility, reliability, and performance improvements on reconfigurable transparent networks are expected to arise from the consolidated assessment of network management and control specifications, as a more accurate evaluation of available M&C techniques. In the network layer, physical parameters aware algorithms are foreseen to pursue reliable network performance. In the physical layer, some new M&C methods were developed and rating of the state-of-the-art reported in literature is given. Optical monitoring implementation and viability is discussed.Publicad

Software Defined Networking with OpenFlow

OpenFlow is an open interface for remotely controlling tables in network switches, routers, and access points. It is considered a turning point in Software Defined Networking (SDN), data center networking and virtualization as, more secure and efficient data centers are being built using OpenFlow. It defines a protocol that lets a controller use a common set of instructions to add, modify, or delete entries in a switch's forwarding table. Starting with an introduction to SDN and OpenFlow, you will learn about the role of each building block, moving onto demonstrations of how SDN/OpenFlow can be used to provide new services and features, which will change the way that networking works and the innovative business impacts. By the end of this practical guide, you will have an insight into the Software Defined Networking and OpenFlow fundamentals. Packed with detail, this book will walk you through the essentials; you will learn about the OpenFlow protocol, switches, and controllers. Following on from this, you will be taken through a number of practical, hands-on examples on how to use a network emulation platform called OpenFlow laboratory. You will learn how to develop your innovative network application using the OpenFlow controller’s API quickly, and test your network application without commissioning any OpenFlow hardware equipment. You will also be introduced to the concept of Software Defined Networking and the details of OpenFlow’s protocol, along with the building blocks of an OpenFlow networking deployment. This book will teach you how to setup your OpenFlow/SDN laboratory using state-of-the-art technology and open source offerings

Dynamic Impairment-Aware Routing and Wavelength Assignment

Dynamic impairment-aware routing and wavelength assignment (IA-RWA) applies to dynamic core wavelength-division multiplexing (WDM) networks and refers to the process that is responsible for the computation of lightpaths (LPs) for traffic demands arriving during network operation. During this process, the effect of single-channel and multichannel impairments needs to be taken into account so as to compute LPs with strong quality of transmission (QoT) and not to disrupt the traffic that is already established in the network. In addition to ensuring acceptable QoT, the online application of IA-RWA seeks also to minimize the execution time needed per connection. Minimizing the LP setup time is critical during network operation, and the delay experienced due to the LP computation depends largely on the algorithmic implementation and particularly on the way physical-layer impairments (PLIs) are considered. Finally IA-RWA needs to be supported by a properly enhanced control plane that essentially enables the dynamic impairment-aware networking vision