Abstract
Access control is a crucial part of a system's security, restricting what actions users can perform on resources. Therefore, access control is a core component when dealing with eHealth data and resources, discriminating which is available for a certain party. We consider that current systems that attempt to assure the share of policies between facilities are prone to system's and network's faults and do not assure the integrity of policies life-cycle. By approaching this problem with a blockchain where the operations are stored as transactions, we can ensure that the different facilities have knowledge about all the parts that can act over the eHealth resources while maintaining integrity, auditability, and authenticity.

Abstract
The Internet of Things is progressively getting broader, evolving its scope while creating new markets and adding more to the existing ones. However, both generation and analysis of large amounts of data, which are integral to this concept, may require the proper protection and privacy-awareness of some sensitive information. In order to control the access to this data, allowing devices to verify the reliability of their own interactions with other endpoints of the network is a crucial step to ensure this required safeness. Through the implementation of a blockchain-based Public Key Infrastructure connected to the Keybase platform, it is possible to achieve a simple protocol that binds devices’ public keys to their owner accounts, which are respectively supported by identity proofs. The records of this blockchain represent digital signatures performed by this Keybase users on their respective devices’ public keys, claiming their ownership. Resorting to this distributed and decentralized PKI, any device is able to autonomously verify the entity in control of a certain node of the network and prevent future interactions with unverified parties. © 2020, Springer Nature Switzerland AG.

Abstract
Cloud computing has emerged as the de facto approach for providing services over the Internet. Although having increased popularity, challenges arise in the management of such environments, especially when the cloud service providers are constantly evolving their services and technology stack in order to maintain position in a demanding market. This usually leads to a combination of different services, each one managed individually, not providing a big picture of the architecture. In essence, the end state will be too many resources under management in an overwhelming heterogeneous environment. An infrastructure that has considerable growth will not be able to avoid its increasing complexity. Thus, this papers introduces liveness as an attempt to increase the feedback-loop to the developer in the management of cloud architectures. This aims to ease the process of developing and integrating cloud-based systems, by giving the possibility to understand the system and manage it in an interactive and immersive experience, thus perceiving how the infrastructure reacts to change. This approach allows the real-time visualization of a cloud infrastructure composed of a set of Amazon Web Services resources, using visual city metaphors.

Abstract

Abstract
Any software system that has a considerable growing number of features will suffer from essential complexity, which makes the understanding of the software artifacts increasingly costly and time-consuming. A common approach for reducing the software understanding complexity is to use software visualizations techniques. There are already several approaches for visualizing software, as well as for extracting the information needed for those visualizations. This paper presents a novel approach to tackle the software complexity, delving into the common approaches for extracting information about software artifacts and common software visualization metaphors, allowing users to dive into the software system in a live way using virtual reality (VR). Experiments were carried out in order to validate the correct extraction of metadata from the software artifact and the corresponding VR visualization. With this work, we intend to present a starting point towards a Live Software Development approach.

Abstract