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The development of cloud computing services is speeding up the rate in which the organizations outsource their computational services or sell their idle computational resources. Even though migrating to the cloud remains a tempting trend from a financial perspective, there are several other aspects that must be taken into account by companies before they(More)
We present Lyra2, a password hashing scheme (PHS) based on cryptographic sponges. Lyra2 was designed to be strictly sequential (i.e., not easily parallelizable), providing strong security even against attackers that uses multiple processing cores (e.g., custom hardware or a powerful GPU). At the same time, it is very simple to implement in software and(More)
We present Marvin, a new parallelizable message authentication code based on the ALRED family. The new algorithm is designed with resource-constrained platforms in mind and explores the structure of an underlying block cipher to provide security at a small cost in terms of memory needs. Also, we show how Marvin can be used as an authentication-only function(More)
Wireless Sensor Networks (WSNs) have a vast field of applications, including deployment in hostile environments. Thus, the adoption of security mechanisms is fundamental. However, the extremely constrained nature of sensors and the potentially dynamic behavior of WSNs hinder the use of key management mechanisms commonly applied in modern networks. For this(More)
For the last decade, elliptic curve cryptography has gained increasing interest in industry and in the academic community. This is especially due to the high level of security it provides with relatively small keys and to its ability to create very efficient and multifunctional cryptographic schemes by means of bilinear pairings. Pairings require(More)
OBJECTIVE To conduct a comprehensive survey of mobile health (mHealth) research initiatives in Brazil, discussing current challenges, gaps, opportunities and tendencies. METHODS Systematic review of publicly available electronic documents related to mHealth, including scientific publications, technical reports and descriptions of commercial products.(More)
Privacy is a key concern in Location Based Applications (LBAs), especially due to their intensive use resource constrained devices in which general purpose ciphers are dicult to deploy. In this paper, we address this issue by specifying a new, faster key-schedule algorithm for the Curupira block cipher. This special-purpose cipher follows the Wide Trail(More)
—Security is an important concern in any modern network. This also applies to Wireless Sensor Networks (WSNs), especially those used in applications that monitor sensitive information (e.g., health care applications). However, the highly constrained nature of sensors impose a difficult challenge: their reduced availability of memory, processing power and(More)