International Institute of Information Technology, Hyderabad

About: International Institute of Information Technology, Hyderabad is a education organization based out in Hyderabad, India. It is known for research contribution in the topics: Computer science & Authentication. The organization has 2048 authors who have published 3677 publications receiving 45319 citations. The organization is also known as: IIIT Hyderabad & International Institute of Information Technology (IIIT).

Crenarchaeal chromatin proteins Cren7 and Sul7 compact DNA by inducing rigid bends

Abstract: Archaeal chromatin proteins share molecular and functional similarities with both bacterial and eukaryotic chromatin proteins. These proteins play an important role in functionally organizing the genomic DNA into a compact nucleoid. Cren7 and Sul7 are two crenarchaeal nucleoid-associated proteins, which are structurally homologous, but not conserved at the sequence level. Co-crystal structures have shown that these two proteins induce a sharp bend on binding to DNA. In this study, we have investigated the architectural properties of these proteins using atomic force microscopy, molecular dynamics simulations and magnetic tweezers. We demonstrate that Cren7 and Sul7 both compact DNA molecules to a similar extent. Using a theoretical model, we quantify the number of individual proteins bound to the DNA as a function of protein concentration and show that forces up to 3.5 pN do not affect this binding. Moreover, we investigate the flexibility of the bending angle induced by Cren7 and Sul7 and show that the protein–DNA complexes differ in flexibility from analogous bacterial and eukaryotic DNA-bending proteins.

2PAKEP: Provably Secure and Efficient Two-Party Authenticated Key Exchange Protocol for Mobile Environment

Abstract: With the increasing use of mobile devices, a secure communication and key exchange become the significant security issues in mobile environments. However, because of open network environments, mobile user can be vulnerable to various attacks. Therefore, the numerous authentication and key exchange schemes have been proposed to provide the secure communication and key exchange. Recently, Qi and Chen proposed an efficient two-party authentication key exchange protocol for mobile environments in order to overcome the security weaknesses of the previous authentication and key exchange schemes. However, we demonstrate that Qi and Chen’s scheme is vulnerable to various attacks such as impersonation, offline password guessing, password change, and privileged insider attacks. We also show that Qi and Chen’s scheme does not provide anonymity, efficient password change mechanism, and secure mutual authentication. In this paper, to overcome the outlined abovementioned security vulnerabilities, we propose a secure and efficient two-party authentication key exchange protocol, called 2PAKEP, that hides user’s real identity from an adversary using a secret parameter. 2PAKEP also withstands various attacks, guarantees anonymity, and provides efficient password change mechanism and secure mutual authentication. In addition, we prove that 2PAKEP provides the secure mutual authentication using the broadly accepted Burrows–Abadi–Needham logic and the session key security using the formal security analysis under the widely accepted real-or-random model. Moreover, the formal security verification using the popular simulated software tool, Automated Validation of Internet Security Protocols and Applications, on 2PAKEP shows that the replay and man-in-the-middle attacks are protected. In addition, we also analyze the performance and security and functionality properties of 2PAKEP and compare these with the related existing schemes. Overall, 2PAKEP provides better security and functionality features, and also the communication and computational overheads are comparable with the related schemes. Therefore, 2PAKEP is applicable to mobile environment efficiently.

Part-based Graph Convolutional Network for Action Recognition

Abstract: Human actions comprise of joint motion of articulated body parts or `gestures'. Human skeleton is intuitively represented as a sparse graph with joints as nodes and natural connections between them as edges. Graph convolutional networks have been used to recognize actions from skeletal videos. We introduce a part-based graph convolutional network (PB-GCN) for this task, inspired by Deformable Part-based Models (DPMs). We divide the skeleton graph into four subgraphs with joints shared across them and learn a recognition model using a part-based graph convolutional network. We show that such a model improves performance of recognition, compared to a model using entire skeleton graph. Instead of using 3D joint coordinates as node features, we show that using relative coordinates and temporal displacements boosts performance. Our model achieves state-of-the-art performance on two challenging benchmark datasets NTURGB+D and HDM05, for skeletal action recognition.

Provably secure biometric-based user authentication and key agreement scheme in cloud computing

Abstract: Cloud computing, the conjoin of many types of computing, has made a great impact on the life of everyone. People from anywhere can access the different cloud-based services by using the Internet. A user, who wants to access some cloud-based service, needs to register himself/herself to an authority service provider, and after that, he/she can use the service. To access the service, each user needs to authenticate to that particular cloud server. Several user authentication schemes for cloud computing have been presented but mostly have limitations/drawbacks as they are prone to various known attacks, such as privileged insider, user and server impersonation, and strong reply attacks, and they also have lack of functionality features. Moreover, these schemes do not provide efficient password change phase. In order to overcome these drawbacks, we propose a new provably secure biometric-based user authentication and key agreement scheme for cloud computing. The proposed scheme overcomes the weaknesses of the existing schemes and supports extra functionality features including user anonymity and efficient password and biometric update phase for multi-server environment. The careful formal security analysis under standard model and informal security analysis and the simulation results for formal security verification using the most acceptable AVISPA tool show that the proposed scheme is secure against various known possible attacks. The analysis of computation and communication overheads of our scheme depicts its efficiency over other related existing schemes, and thus, the proposed scheme is suitable for the cloud computing environment. Copyright © 2016 John Wiley & Sons, Ltd.