DSpace Collection:https://hdl.handle.net/10316/418142024-03-28T12:36:52Z2024-03-28T12:36:52ZFailure Simulation in Software-Defined Networks with Differential Link AvailabilityMelo, Manuel Paulo AlbuquerqueJorge, Luísa Maria GarciaGomes, Teresa Martinez dos Santoshttps://hdl.handle.net/10316/954442022-05-25T04:18:21Z2021-07-12T00:00:00ZTitle: Failure Simulation in Software-Defined Networks with Differential Link Availability
Authors: Melo, Manuel Paulo Albuquerque; Jorge, Luísa Maria Garcia; Gomes, Teresa Martinez dos Santos
Abstract: In Software-Defined Networks (SDN) the placement of controllers is an important factor for overall network reliability. Whereas most studies assume that all links have similar link failure rates/availability, placing controllers taking into account differences in link availability can yield advantages. This is even more relevant if the network is designed with a particular subset of high availability links (a spine). After presenting integer linear programming formulations to support controller placement considering differential link availability, we propose a simulation approach to verify the reliability change due to that placement. From a simulational study using 2 networks, 30 different link availability configurations we found a definite advantage in overall reliability in using the knowledge of high availability links to place the controllers. However, while there were also advantages to using certain spines for individual networks, these advantages were not uniform, and varied according to networks, the number of controllers placed and link availability ratio. Further work is suggested to check whether fault patterns may influence the reliability advantage of individual spines.2021-07-12T00:00:00ZInitial Coin Offering (ICO): a systematic review of the literatureMoxotó, Ana ClaudiaMelo, Manuel Paulo AlbuquerqueSoukiazis, Eliashttps://hdl.handle.net/10316/954432022-05-25T04:18:36Z2021-01-01T00:00:00ZTitle: Initial Coin Offering (ICO): a systematic review of the literature
Authors: Moxotó, Ana Claudia; Melo, Manuel Paulo Albuquerque; Soukiazis, Elias
Abstract: Initial ICO coin offerings have emerged as a new business financing mechanism. ICOs have raised more than $ 31.14 billion by 2019, sparking interest in finance studies. Despite ongoing scientific research on the topic, academic knowledge remains limited and fragmented. This study aims to conduct a systematic review of the literature with 30 contributions from journals published until January 2020. Based on an in-depth analysis of the publications identified, we describe the landscape of the field of ICOs focusing on two aspects. First, we conducted an analysis of the empirical articles that addressed the success determinants of ICOs. Second, we categorize relevant contributions in five different perspectives: human and social capital, technological characteristics, governance and legal aspects and financial details of the campaign. Thematic analysis was carried out to address dominant themes and subthemes in each perspective.2021-01-01T00:00:00ZAvaliação da resiliência em adolescentes portugueses: novos contributos para o estudo das versões longa e breve da Resilience Scale de Wagnild e Young (1993)Pinheiro, M. R.Matos, A. P.https://hdl.handle.net/10316/470432022-09-08T11:34:55Z2013-01-01T00:00:00ZTitle: Avaliação da resiliência em adolescentes portugueses: novos contributos para o estudo das versões longa e breve da Resilience Scale de Wagnild e Young (1993)
Authors: Pinheiro, M. R.; Matos, A. P.2013-01-01T00:00:00Z