Secure and Efficient Construction of Broadcast Encryption with Dealership

Broadcast encryption with dealership (BED) has been proposed to achieve more innovative and scalable business models for broadcast services. It has an extensive application future. However, designing secure BED is a challenging task. The only known BED construction sofar is by Gritti et al. We aim to raise the profile of BED primitives which has not received much attention despite of its importance. This paper presents a selectively chosen plaintext attack (CPA) secure BED scheme supporting maximum number of accountability and privacy (hides the group of users from broadcaster). Our scheme is a key encapsulation mechanism and practically more efficient. It reduces the parameter sizes and computation cost compared to Gritti et al. More interestingly, the broadcaster does not need to rely on users to detect the dishonest dealer. We provide concrete security analysis of our design under reasonable assumptions

Adaptively Secure Recipient Revocable Broadcast Encryption with Constant size Ciphertext

In this paper, we put forward the first adaptively secure recipient revocable broadcast encryption (RR-BE) scheme in the standard model. The scheme is adaptively secure against chosen plaintext attack (CPA) under the q-weaker Decisional Augmented Bilinear Diffie-Hellman Exponent (q-wDABDHE) assumption. Our scheme compares well with the only existing RR-BE scheme of Susilo et al. which is selectively secure in the random oracle model. More interestingly, achieving adaptive security in the standard model does not blow up the communication cost in our construction. To be more precise, the size of the ciphertext which is broadcasted by the broadcaster is constant

Enhanced Outsider-anonymous Broadcast Encryption with Subset Difference Revocation

This paper puts forward an efficient broadcast encryption in public key setting employing ternary tree subset difference method for revocation. It provides outsider anonymity disabling the revoked users from getting any information of message and concealing the set of subscribed users from the revoked users. Our approach utilizes composite order bilinear group setting and exhibits significant improvement in the broadcast efficiency. The proposed scheme compares favourably over the existing similar schemes in standard model. The public key and secret key sizes are poly-logarithmic while the ciphertext size is sub linear in total number of users. Our scheme achieves selective security against chosen plaintext attack in the standard model under reasonable assumptions

Physics Potential of the ICAL detector at the India-based Neutrino Observatory (INO)

The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) is designed to study the atmospheric neutrinos and antineutrinos separately over a wide range of energies and path lengths. The primary focus of this experiment is to explore the Earth matter effects by observing the energy and zenith angle dependence of the atmospheric neutrinos in the multi-GeV range. This study will be crucial to address some of the outstanding issues in neutrino oscillation physics, including the fundamental issue of neutrino mass hierarchy. In this document, we present the physics potential of the detector as obtained from realistic detector simulations. We describe the simulation framework, the neutrino interactions in the detector, and the expected response of the detector to particles traversing it. The ICAL detector can determine the energy and direction of the muons to a high precision, and in addition, its sensitivity to multi-GeV hadrons increases its physics reach substantially. Its charge identification capability, and hence its ability to distinguish neutrinos from antineutrinos, makes it an efficient detector for determining the neutrino mass hierarchy. In this report, we outline the analyses carried out for the determination of neutrino mass hierarchy and precision measurements of atmospheric neutrino mixing parameters at ICAL, and give the expected physics reach of the detector with 10 years of runtime. We also explore the potential of ICAL for probing new physics scenarios like CPT violation and the presence of magnetic monopoles.Comment: 139 pages, Physics White Paper of the ICAL (INO) Collaboration, Contents identical with the version published in Pramana - J. Physic