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Network Management as Code is presented to manage the infrastructure and deployment of control functions in a declarative manner by adopting GitOps in open disaggregated optical networks. We introduce an Automation Engine that analyzes topology changes to trigger the Continuous Delivery procedure of SDN applications on a micro-service architecture.

Over the past decade, the teaching of coding and computational thinking has become increasingly important in the school environment. If before they were a secondary part of the teaching program and provided only, at best, from the age of eleven and up, it is now clear that they should play a relevant role in the school curriculum as soon as possible. In recent years, many solutions, both papery and software applications, have been developed for encoding. However, the remaining problem is that every available solution has been designed for a very precise and limited scope, both of age and skills, without thinking of a more generalizable use for a long period. This work therefore aims to choose some of the tools available, designed for different needs but sufficiently similar in order to allow the development of a fluid and continuous coding educational path, gradually adding new complexities, starting from the age of three in the school of childhood, up to high school.

The work discussed in this paper stems from a particular need that recently arise in our company. In order to better exploit the fiber optics network in terms of resource allocation in the Bologna city Metropolitan Area Network, a new tool is required. The aim of this tool is to visualize and understand the municipality fiber optics allocation in order to take informed decisions about how and where to use them and/or to eventually plan infrastructure updates when no resources are left or are not sufficient. We describe the design and implementation of the very first prototype of our tool aiming to tackle this need.

In recent years, the research has focused a lot on the development of ‘smart textiles’ since these have an incredible versatility and the only limit of the applicability of these smart textiles is the imagination. The Knitronix company has patented a method of production of smart textiles and has produced an innovative textile temperature sensor that is categorized as RTD type, a type of device able to convert the temperature variation into a resistance variation. In this paper the main metrological characteristics of this new sensor will be analyzed and a short comparison with the best-selling temperature RTD type sensors: PT100 probes, will be proposed to demonstrate - that the textile is efficient from a technical point of view and is a competitive product respect to the PT100.

We present an approach to perform 3D pose estimation of multiple people from a few calibrated camera views. Our architecture, leveraging the recently proposed unprojection layer, aggregates feature-maps from a 2D pose estimator backbone into a comprehensive representation of the 3D scene. Such intermediate representation is then elaborated by a fully-convolutional volumetric network and a decoding stage to extract 3D skeletons with sub-voxel accuracy. Our method achieves state of the art MPJPE on the CMU Panoptic dataset using a few unseen views and obtains competitive results even with a single input view. We also assess the transfer learning capabilities of the model by testing it against the publicly available Shelf dataset obtaining good performance metrics. The proposed method is inherently efficient: as a pure bottom-up approach, it is computationally independent of the number of people in the scene. Furthermore, even though the computational burden of the 2D part scales linearly with the number of input views, the overall architecture is able to exploit a very lightweight 2D backbone which is orders of magnitude faster than the volumetric counterpart, resulting in fast inference time. The system can run at 6 FPS, processing up to 10 camera views on a single 1080Ti GPU.

This research full paper describes our experience in teaching parallel programming for students without previous knowledge of basic concepts of computing, comparing their levels of learning. The use of parallel software grew considerably in recent years due to the increasing availability of multi and many-core devices. The evolution of hardware and software resources collaborated for a remarkable computational processing power offered by parallel programs. However, parallel programming is taught usually in more advanced years of the undergraduate computer courses, due to its supposed prerequisites as sequential programming, operating systems, computer architectures and others. Postponing parallel programming teaching hinder students to apply parallelism other subjects, reducing the probability of these future professionals think on parallel solutions naturally. We executed 05 experiments teaching parallel programming subjects for 252 students. We analyzed whether students without prerequisites could learn parallel programming in the same level verified with students with prior computing knowledge. We used three different teaching methodologies: traditional, Problem Based Learning (PBL), and Team-Based Learning (TBL). The teaching and learning evaluation took into account such metrics: parallelism thinking of students, use of programming-model, correct output of the program, source-code readability and satisfaction of the students. The paper shows that it is possible to teach parallel programming to students without previous knowledge of computing, obtaining high scores and interest in such learning. Our results contribute positively to disseminate parallel programming, which is vital to extract performance from nowadays computers.

This research full paper describes the use of challenges to teach parallel programming, regardless of teaching methodology (traditional, Problem-Based Learning and others) or programming-contest support systems. We verify how challenges contribute to the learning of parallel programming, considering technical and motivational aspects. Studies demonstrate the potential of using programming contests as educational resources at the end of courses, encouraging students to practice and learn more about parallel programming. However, there are no proposals exploring programming challenges as part of the learning process, since the beginning of the course. This paper presents four different experiments applying challenges to teach parallel programming for undergraduate and graduate students. We evaluated different teaching/learning methodologies, contexts, educational resources (including programming marathon systems), and groups of students. Considering all the experiments, almost 250 students participated and were evaluated. We developed and applied 58 challenges to analyze theoretical and practical knowledge about parallel programming. Different metrics were used to evaluate the students during the experiments: theoretical assessments, source-code quality, program output correctness, and student´s receptivity/motivation to learning from challenges. Results from experiments show scores of up to 96% of learning on technical aspects and up to 83% on student satisfaction. Challenges stimulated the development of high-quality parallel solutions and promoted a healthy environment among students, where the lightly-competitive context contributed to create a collaborative atmosphere. The use of programming marathon systems as an educational tool is not imperative. The use of challenges for the students’ learning, not on their classification, showed that it is possible to teach parallel programming, maintaining students focused and motivated.

This research full paper identifies how the teaching of parallel computing has been developing over the years. The learning of parallel and distributed computing is fundamental for computing professionals, due to the popularization of parallel architectures. Teaching parallel computing involves theoretical concepts and the development of practical skills. Its content is dense and comprises different disciplines in computer courses. Although there is growing concerned about this type of teaching, the organization and depth of parallel computing teaching at universities change widely. The available literature on the teaching of parallel computing shows some experiences about how to teach parallel computing; however, it is not easy to determine the state of the art with challenges and gaps. Our objective is to identify essential aspects related to the teaching of parallel computing as methodologies, supporting resources, subjects taught, the satisfaction of students with learning and curricula. We carried out a systematic mapping to extract information from the literature, which is composed of three phases: planning, conduction, and reporting. We initially selected 819 papers from the Scopus, IEEE, ACM, and Google Scholar databases. After a previous analysis, we performed a full read of 94 papers. The use of different teaching methodologies appears in the publications, however, the traditional teaching methodology still is the most used. There is a small number of students in parallel computing courses, a concern of different authors. Educational software or hardware resources are reported, with software proposals corresponding to most of them. The teaching of parallel computing at the beginning of undergraduate courses appear in different papers. This paper contributes to research in teaching parallel computing, pointing out the state of the art of this area, highlighting challenges that should be the focus of investigations.

The Internet of Things has revolutionized people's way of life by providing a range of services and products that benefit society in a variety of sectors. However, as it is an emerging technology, there are many challenges to be addressed, such as access control. Based on this premise, in this paper, we analyzed which factors impact the final response time to perform access control in the cloud of things with the use of symmetric and asymmetric signatures in JSON tokens. We developed a prototype of a modular architecture as a base platform for our evaluations. In addition, we adopted the process of evaluating computer systems performance with an experimental design to collect the use of processing and memory metrics. The results show that the biggest bottleneck is in the process of generating and signing the token with the greatest impact for the asymmetric signature when the number of requests is high. For a low number of requests, the results show similar values for symmetric and asymmetric cryptography.

Performance is one example of the Extra-Functional Properties (EFPs), an essential part of software development with limited resources. In such a context of software development, containers represent a widely used abstraction technology that requires fewer resources, when compared to hypervisor-based virtualization. Containers provide access to environments and speed up development by abstracting the underlying infrastructure layer for different application domains. Volume sharing is a usual abstraction provided by containers for data persistence, which can be accomplished, especially with Network File System (NFS) or Docker’s sharing method. Evaluate the performance of these volumes in containers is critical to software development; however, we did not find available in the literature such evaluation. This paper describes the volume sharing performance for containers using NFS and Docker, which is essential for data persistence. We evaluated the performance of these shared volumes by simulating three application domains: database accesses from a benchmark, direct reads and writes in the file systems and concurrent accesses from an MPI parallel program. Our results show significant differences among the distinct volume sharing methods analyzed for Docker and NFS. While asynchronous NFS has better performances for the set composed of heavy workloads, bursting read and write sequences, the Docker volumes, by the other hand, outperformed for processes with concurrent accesses when using a parallel program.

Cloud computing is a revolutionary paradigm in relation to its characteristics which can be highlighted the high connectivity, elasticity, assignment of measurable services and ease of management. These attributes favor the promotion of this technology, such as the increasing use of virtualization services in public and private institutions. Therefore, part of the efficiency of this service is based on the allocation of virtual resources that enable different configurations in different applications. In relation to this context, this paper aims to present the allocation module of the Architecture Management of Hybrid Resources in Private cloud Architecture (MoHRiPA), which was modeled with the purpose of providing high performance during the allocation of virtual machines. Its architecture and component specification will be presented, with emphasis on the resource allocation module that has hybrid properties, which makes it possible to support the use of different virtualization tools. The results obtained are described by means of a complete factorial planning with their respective more accurate analyzes about the functionalities and peculiarities of the allocation module.

This paper tackles the problem of verifying if the available bandwidth between any node over the Lepida ScpA Regional fiber optics network corresponds to active contractual obligations signed by local network operators. This is the key factor that must be quickly addressed when Lepida ScpA receives new bandwidth requests from local operators. Since now, this verification process has been carried out almost manually. The introduction of this tool allowed a very significant shrink of the verification time. Our tool is based on a graph representation of the network and on well known graph theories algorithms. This paper is about its design and development; we describe the challenges and the choices we addressed during the process of implementing our tool.

This paper is about the design and the implementation of Lepida ScpA BigData infrastructure. Our goal is to provide the Regional PA with proper tools to address future challenges such as planning the allocation of resources and creating new business models involving public and private organizations. Our first design of the infrastructure started from a specific scenario and addresses a particular aspect: ingesting the Regional public WiFi data traffic and gathering interesting analytics. We describe the challenges we faced and the choices we made during the process and the final results we achieved.

This paper is about the deployment of Lepida ScpA LoRAWAN infrastructure. We describe the challenges and the choices we addressed during the process of implementing our LoRA architecture. The lack of information resources, sometimes their poor quality (especially concerning commercial devices) both online and in literature and the lack of device standardization are major issues when building a complex network infrastructure. The aim of this work is to contribute to the LoRAWAN community by providing a basic reference and identifying best practices concerning the actual implementation and deployment of a real world, scalable LoRAWAN infrastructure.

This paper proposes the resolution of the optimal reactive dispatch (ORD) problem for the combined objective of minimizing active power losses and voltage profile improvement on load buses considering discrete variables and limited the number of control adjustments. The problem is modeled as a multiobjective ORD problem, a resolution strategy which models discrete control variables by a polynomial discretization function and considers limited number of control adjustments is proposed. The proposed solution method is based on transformation of the original mixed integer nonlinear programming (MINLP) problem with mixed continuous, discrete and binary control variables into a nonlinear programming (NLP) problem with only continuous variables. The method has been tested with IEEE test systems with 118 and 300 buses and the success of the proposed strategy has been observed with the resulting high quality solutions with high speed computation.