Um protocolo de autorização para internet das coisas baseado em atributos e informações de contexto

Orientador: Carlos Alberto MazieroDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Exatas, Programa de Pós-Graduação em Informática. Defesa : Curitiba, 18/02/2019Inclui referências: p.59-63Área de concentração: Ciência da ComputaçãoResumo: Com a Internet das Coisas, a ubiquidade de dispositivos cresce a cada dia. Controlar e garantir comunicação segura e amigável ao usuário final continua um desafio. Este trabalho propõe um protocolo de autorização para dispositivos baseado em atributos e informações de contexto. As informações de contexto são observações disponíveis em sensores dos dispositivos, tais como: luz, temperatura, microfone - para citar algumas. Este contexto provê elementos que auxiliam nas decisões de segurança, como fatores complementares de autorização. Agrega-se ao contexto um fator social dos dispositivos, auxiliando na avaliação de acessos e respectivos riscos. Este fator social consiste tanto no histórico das observações realizadas pelo dispositivo, quanto no cumprimento de suas funções (comportamento esperado). De posse destas informações de contexto e de atributos do pedido (requisitante e risco da informação), o protocolo classifica o risco e decide se efetiva ou não o pedido. As informações de contexto são base para o modelo de confiança entre os dispositivos, sendo utilizadas como validações entre os mesmos. Somado ao protocolo apresentado, discute-se o modelo de ameaças e respectivas mitigações as quais o protocolo resiste satisfatoriamente. Na sequencia, apresenta-se o uso e análise específica de um atributo: a luminância. Discute-se o uso da luminância para representação de um mesmo ambiente e respectivos resultados desta pesquisa. Por fim, algumas considerações e possibilidades de pesquisa em aberto. Palavras-chave: IoT, Segurança, Autorização, ABAC, Contexto, Protocolo, Luminância.Abstract: Internet of Things grows the devices' ubiquity constinuously. It remains a challenge to control and ensure a user-friendly secure communication. This work presents an context-aware attributebased authorization protocol. The context provides elements that helps decision making. The devices' social factor are included in the context, assisting in access evaluation and its risks. Context information is gathered throught devices' sensors, such as: light, temperature, sound - to list some examples. This context provides aid in security decisions, as complementary factors of authorization. A devices' social factor is added to the context, aiding the accesses evaluation and its risks. This social factor consists both the observations historical made by devices, and in by execution of its functions (expected behavior). With this context information and request attributes (asker and information risk), the protocol classifies the risk and decides whether or not will honor the request. Context information is the basis for the trust model between devices, and is used as validation between devices. In addition to the presented protocol, the threat model and its mitigations are discussed, which the protocol resists satisfactorily. In sequence, the analysis of an attribute use is presented: luminance. We discuss the luminance's use to represent same environment. Finally, we conclude with some considerations and open research possibilities. Keywords: IoT, Security, Authorization, ABAC, Context-Aware, Protocol, Luminance

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