40-bit encryption

About: 40-bit encryption is a research topic. Over the lifetime, 5434 publications have been published within this topic receiving 149016 citations.

Server-Aided Public Key Encryption With Keyword Search

Abstract: Public key encryption with keyword search (PEKS) is a well-known cryptographic primitive for secure searchable data encryption in cloud storage. Unfortunately, it is inherently subject to the (inside) offline keyword guessing attack (KGA), which is against the data privacy of users. Existing countermeasures for dealing with this security issue mainly suffer from low efficiency and are impractical for real applications. In this paper, we provide a practical and applicable treatment on this security vulnerability by formalizing a new PEKS system named server-aided public key encryption with keyword search (SA-PEKS). In SA-PEKS, to generate the keyword ciphertext/trapdoor, the user needs to query a semitrusted third-party called keyword server (KS) by running an authentication protocol, and hence, security against the offline KGA can be obtained. We then introduce a universal transformation from any PEKS scheme to a secure SA-PEKS scheme using the deterministic blind signature. To illustrate its feasibility, we present the first instantiation of SA-PEKS scheme by utilizing the Full Domain Hash RSA signature and the PEKS scheme proposed by Boneh et al. in Eurocrypt 2004. Finally, we describe how to securely implement the client-KS protocol with a rate-limiting mechanism against online KGA and evaluate the performance of our solutions in experiments.

A new modified version of Advanced Encryption Standard based algorithm for image encryption

Abstract: Security in transmission storage of digital images has its importance in today's image communications and confidential video conferencing. Due to the increasing use of images in industrial process, it is essential to protect the confidential image data from unauthorized access. Advanced Encryption Standard (AES) is a well known block cipher that has several advantages in data encryption. However, it is not suitable for real-time applications. In this paper, we analyze and present a modification to the Advanced Encryption Standard (MAES) to reflect a high level security and better image encryption. The modification is done by adjusting the ShiftRow Transformation. Detailed results in terms of security analysis and implementation are given. Experimental results verify and prove that the proposed modification to image cryptosystem is highly secure from the cryptographic viewpoint. The results also prove that with a comparison to original AES encryption algorithm the modified algorithm gives better encryption results in terms of security against statistical attacks.

Selective encryption of wavelet-packet encoded image data: efficiency and security

Abstract: Selective encryption provides the ability to strike a balance between security and processing demands, e.g., in mobile clients. Image encoding using wavelets, and especially wavelet packets, can be used for efficient selective encryption. We will show how two such methods work and discuss their advantages and disadvantages in terms of security and speed.

Data-image-video encryption

Abstract: This paper describes the most representative algorithms and standards for the encryption of data, digital images and MPEG video. The general model a typical encryption/decryption system about the security principle is discussed. Data encryption mainly is the scrambling of the content of data, text, image, audio, and video and to make the data unreadable, invisible or incomprehensible during ciphertext transmission. The goal is to protect the content of the data against the attackers. The reverse of data encryption is data decryption, which recovers the original data. There are two types of encryption/decryption key: the public-key system and the private-key system. The most promising features are joint lossless compression, joint encryption and hiding based on SCAN language which analyses the unique properties of digital image and video and search for high security algorithms to reduce the overall computational cost.

An Efficient Certificateless Encryption for Secure Data Sharing in Public Clouds

Abstract: We propose a mediated certificateless encryption scheme without pairing operations for securely sharing sensitive information in public clouds. Mediated certificateless public key encryption (mCL-PKE) solves the key escrow problem in identity based encryption and certificate revocation problem in public key cryptography. However, existing mCL-PKE schemes are either inefficient because of the use of expensive pairing operations or vulnerable against partial decryption attacks. In order to address the performance and security issues, in this paper, we first propose a mCL-PKE scheme without using pairing operations. We apply our mCL-PKE scheme to construct a practical solution to the problem of sharing sensitive information in public clouds. The cloud is employed as a secure storage as well as a key generation center. In our system, the data owner encrypts the sensitive data using the cloud generated users' public keys based on its access control policies and uploads the encrypted data to the cloud. Upon successful authorization, the cloud partially decrypts the encrypted data for the users. The users subsequently fully decrypt the partially decrypted data using their private keys. The confidentiality of the content and the keys is preserved with respect to the cloud, because the cloud cannot fully decrypt the information. We also propose an extension to the above approach to improve the efficiency of encryption at the data owner. We implement our mCL-PKE scheme and the overall cloud based system, and evaluate its security and performance. Our results show that our schemes are efficient and practical.