Abstract

Abstract
Some governments do not consider metadata as personal data, and so not in the scope of privacy regulations. However, often, metadata gives more relevant information than the actual content itself. Metadata can be very useful to identify, locate, understand and manage personal data, i.e., information that is eminently private in nature and under most privacy regulation should be anonymized or deleted if users have not give their consent. In voice calls, we are facing a critical situation in terms of privacy, as metadata can identify who calls to whom and the duration of the call, for example. In this work, we investigate privacy properties of voice calls metadata, in particular when using secure VoIP, giving evidence of the ability to extract sensitive information from its ("secure") metadata. We find that ZRTP metadata is freely available to any client on the network, and that users can be re-identified by any user with access to the network. Also, we propose a solution for this problem, suitable for all the ZRTP-based implementations.

Abstract
With the constant ICT evolution, the way users interact with e-commerce platforms (EC) is changing and there are constantly emerging new needs both from customers, such as the possibility of customization and individual personalization, and from business operators. As argued by existing literature, EC is a very relevant tool for the overall development of territories, especially those with inherent constraints, such as low-density regions. This work seeks to propose, through a functional and technical analysis, an electronic commerce platform of tourism products and services that allows both the traditional commercialization of products and, in parallel, the negotiation in (almost) real time of tourism products and services, idealized by customers themselves, to which operators can reply via the platform itself.

Abstract
Multi-Agent Epistemic Logic has been investigated in Computer Science [6] to represent and reason about agents or groups of agents knowledge and beliefs. Some extensions aimed to reasoning about knowledge and probabilities and also with a fuzzy semantics have been proposed [7,14]. This paper introduces a parametric method to build graded epistemic logics inspired in the systematic method to build Multi-valued Dynamic Logics introduced in [12,13]. The parameter in both methods is the same: an action lattice [10]. This algebraic structure supports a generic space of agent knowledge operators, as choice, composition and closure (as a Kleene algebra), but also a proper truth space for possible non bivalent interpretation of the assertions (as a residuated lattice).

Abstract

Abstract