A secret sharing scheme is a way of protecting a secret by distributing partial information to a set of participants P in such a way that only authorized subsets of P can recover the secret. The family of authorized subsets is called the access structure of the scheme. In 1979, threshold schemes were proposed to realize threshold access structures, and in 1987, multiple assignment schemes were ...

An ideal secret sharing scheme is a method of sharing a secret key in some key space among a finite set of participants in such a way that only the authorized subsets of participants can reconstruct the secret key from their shares which are of the same length as that of the secret key. The set of all authorized subsets of participants is the access structure of the secret sharing scheme. In th...

Vehicle safety related applications which are drawing increasing attention in public have attracted extensive research both in academic and industry areas. However, it is assumed that one service is offered by one provider, thus forcing vehicle drivers to subscribe to several service providers within limited computation capabilities. In this paper, we present a fine-grained privacy preserving p...

Unlike in traditional computing environments such as operating systems or databases, the authorized user set, the mode of access, users’ access rights, etc., are not predefined in WWW. In order to assign privileges to authorized but not predefined users in dynamic access environments, we propose an approach called authentication-driven authorization. In this approach, authentication is integrat...

Secret sharing is a cryptographic primitive, which is used to distribute a secret among participants in such a way that an authorized subset of participants can uniquely reconstruct the secret and an unauthorized subset can get no information about the secret. It is a fundamental method used in secure multiparty computations, where various distrusted participants cooperate and conduct computati...

Access to hospitals has been dramatically restricted during the COVID 19 pandemic. Indeed, due high risk of contamination by patients and visitors, only essential visits medical appointments have authorized. Restricting hospital access authorized visitors was an important logistic challenge. To deal with this challenge, our institution developed ExpectingU app facilitate patient authorization f...

Secure buildings are currently protected from unauthorized access by a variety of devices. Even though there are many kinds of devices to guarantee the system safety such as PIN pads, keys both conventional and electronic, identity cards, cryptographic and dual control procedures, the people voice can also be used. The ability to verify the identity of a speaker by analyzing speech, or speaker ...

Distributed m-healthcare systems significantly facilitate efficient patient treatment of high quality, while bringing about the challenge of keeping both the confidentiality of the personal health information and the patients’ identity privacy simultaneously. It makes many existing data access control and anonymous authentication schemes inefficient in distributed mhealthcare systems. To solve ...

Definition XML access control refers to the practice of limiting access to (parts of) XML data to only authorized users. Similar to access control over other types of data and resources, XML access control is centered around two key problems: (i) the development of formal models for the specification of access control policies over XML data; and (ii) techniques for efficient enforcement of acce...