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.

Long-Lived Broadcast Encryption

Abstract: In a broadcast encryption scheme, digital content is encrypted to ensure that only privileged users can recover the content from the encrypted broadcast. Key material is usually held in a "tamper-resistant," replaceable, smartcard. A coalition of users may attack such a system by breaking their smartcards open, extracting the keys, and building "pirate decoders" based on the decryption keys they extract. In this paper we suggest the notion of long-lived broadcast encryption as a way of adapting broadcast encryption to the presence of pirate decoders and maintaining the security of broadcasts to privileged users while rendering all pirate decoders useless. When a pirate decoder is detected in a long-lived encryption scheme, the keys it contains are viewed as compromised and are no longer used for encrypting content. We provide both empirical and theoretical evidence indicating that there is a long-lived broadcast encryption scheme that achieves a steady state in which only a small fraction of cards need to be replaced in each epoch. That is, for any fraction β, the parameter values may be chosen in such a way to ensure that eventually, at most β of the cards must be replaced in each epoch. Long-lived broadcast encryption schemes are a more comprehensive solution to piracy than traitor-tracing schemes, because the latter only seek to identify the makers of pirate decoders and don't deal with how to maintain secure broadcasts once keys have been compromised. In addition, long-lived schemes are a more efficient long-term solution than revocation schemes, because their primary goal is to minimize the amount of recarding that must be done in the long term.

A resource-efficient encryption algorithm for multimedia big data

Abstract: Nowadays, multimedia is considered to be the biggest big data as it dominates the traffic in the Internet and mobile phones. Currently symmetric encryption algorithms are used in IoT but when considering multimedia big data in IoT, symmetric encryption algorithms incur more computational cost. In this paper, we have designed and developed a resource-efficient encryption system for encrypting multimedia big data in IoT. The proposed system takes the advantages of the Feistel Encryption Scheme, an Advanced Encryption Standard (AES), and genetic algorithms. To satisfy high throughput, the GPU has also been used in the proposed system. This system is evaluated on real IoT medical multimedia data to benchmark the encryption algorithms such as MARS, RC6, 3-DES, DES, and Blowfish in terms of computational running time and throughput for both encryption and decryption processes as well as the avalanche effect. The results show that the proposed system has the lowest running time and highest throughput for both encryption and decryption processes and highest avalanche effect with compared to the existing encryption algorithms. To satisfy the security objective, the developed algorithm has better Avalanche Effect with compared to any of the other existing algorithms and hence can be incorporated in the process of encryption/decryption of any plain multimedia big data. Also, it has shown that the classical and modern ciphers have very less Avalanche Effect and hence cannot be used for encryption of confidential multimedia messages or confidential big data. The developed encryption algorithm has higher Avalanche Effect and for instance, AES in the proposed system has an Avalanche Effect of %52.50. Therefore, such system is able to secure the multimedia big data against real-time attacks.

Multi-recipient Public-Key Encryption with Shortened Ciphertext

Abstract: In the trivial n-recipient public-key encryption scheme, a ciphertext is a concatenation of independently encrypted messages for n recipients. In this paper, we say that an n-recipient scheme has a "shortened ciphertext" property if the length of the ciphertext is almost a half (or less) of the trivial scheme and the security is still almost the same as the underlying single-recipient scheme. We first present (multi-plaintext, multi-recipient) schemes with the "shortened ciphertext" property for ElGamal scheme and Cramer-Shoup scheme. We next show (single-plaintext, multi-recipient) hybrid encryption schemes with the "shortened ciphertext" property.

Improved Non-committing Encryption Schemes Based on a General Complexity Assumption

Abstract: Non-committing encryption enables the construction of multiparty computation protocols secure against an adaptive adversary in the computational setting where private channels between players are not assumed. While any non-committing encryption scheme must be secure in the ordinary semantic sense, the converse is not necessarily true. We propose a construction of non-committing encryption that can be based on any public-key system which is secure in the ordinary sense and which has an extra property we call simulatability. This generalises an earlier scheme proposed by Beaver based on the Diffie-Hellman problem, and we propose another implementation based on RSA. In a more general setting, our construction can be based on any collection of trapdoor permutations with a certain simulatability property. This offers a considerable efficiency improvement over the first non-committing encryption scheme proposed by Canetti et al. Finally, at some loss of efficiency, our scheme can be based on general collections of trapdoor permutations without the simulatability assumption, and without the common-domain assumption of Canetti et al. In showing this last result, we identify and correct a bug in a key generation protocol from Canetti et al.