March 21, 2016 – 14.00 – Computer Department Seminar Room – NO Building, 8th floor, room 2N8.202 (“salle séminaire”)
Speaker: Veronika Kuchta (ULB)
Title: Distributed Attribute-Based Searchable Encryption
Abstract: In recent years, cloud computing has attracted a lot of attention by providing data storage services for Internet users. To resolve concerns, data owners should encrypt theirs data before uploading it to the cloud. There are services which allow an user to conduct searches without revealing any information about the content of outsourced data. Those services are provided by public key encryption with keyword search. Additional usage of another cryptographic primitive – Attribute-Based Encryption – enables users to control the search over outsourced data according to an access control policy. The biggest problem of such new primitive is to fully trust the one storage server which conducts the search operation over encrypted data. Therefore, a possible solution of this problem is the distributed setting construction which allows to distribute the single point of failure among a group of servers. We provide the first construction of Distributed Attribute-Based Searchable Encryption (DABSE) based on lattices. Attribute-based encryption on lattices is an important but rarely researched question. We prove our scheme secure against chosen ciphertext attacks under the assumption that the underlying schemes, identity based threshold decryption and distributed attribute-based encryption are secure under the hardness of a lattice-based problem – LWE.