Muhai Li

Bio: Muhai Li is an academic researcher. The author has contributed to research in topics: Digital signature & Authenticated encryption. The author has an hindex of 1, co-authored 1 publications receiving 7 citations.

Novel convertible authenticated encryption schemes without using hash functions

Abstract: An authenticated encryption scheme allows a designated recipient to recover the message and then verify its authenticity while keeping the message secret from the public, and a convertible authenticated encryption scheme enables the recipient to convert the signature to an ordinary one so that any third party can verify its validity. The paper shows a weaknesses in Chien's [3] convertible authenticated encryption scheme, then based on the public discrete logarithm hard problem solely, we propose a novel convertible authenticated encryption scheme without using hash functions, and extend it to a (t, n) threshold scheme. The proposed schemes have the following characteristics: Each scheme provides semantic security of the message, that is, after getting a valid signature, any adversary cannot determine whether his guessed message is the actual message signed by the sender by checking if it satisfies the verification equalities. If the signer repudiates her signature, the recipient can prove, without the cooperation with the signer, the dishonesty of the signer to any third party by revealing the message and its converted signature; If the recipient does not reveal the converted signature, any third party cannot check the validity of the message even though he gets the message and its corresponding signature; There are no hash functions in the proposed convertible authenticated encryption schemes.

SCARS: Simplified cryptographic algorithm for RFID systems

Abstract: Radio Frequency Identification (RFID) is a technology made popular by the ability of RFID tags to uniquely represent objects. However, they are severely resource-constrained due to design restrictions. This limits their ability to perform complex computations for security. In RFID systems, the priority is to ensure the integrity of messages and entity authentication. We consider message integrity in our work. To ensure message integrity (i.e., the sent message must be the same as the received message), the actual message is usually hashed and transmitted to the receiver along with the encrypted message. However, it is a challenge for resource-constrained devices such as RFID systems to encrypt a message using different algorithms (such as encryption and hashing algorithm). In this paper, we propose a new symmetric key encryption approach that includes integrity as part of the encryption process for RFID systems. With this approach, we do not need to employ hash functions to achieve message integrity, thus leading to computational efficiency.

HIDE: Hybrid symmetric key algorithm for integrity check, dynamic key generation and encryption

Abstract: This paper proposes a hybrid encryption technique that generates a key dynamically, along with integrity check parameters. Our approach generates the key stream using a chained approach, beginning with an initial preshared key. Subsequent keys are derived using logical operations on intermediate cipher texts and intermediate keys generated in each stage. This is an improvement over chaining techniques, which use a cipher text to derive successive keys. We validate our algorithm by proof-of-concept implementation and security analysis.

Symmetric Encryption Algorithm for RFID Systems using a Dynamic Generation of Key

Abstract: The security of RFID systems come to be a major subject today, notably for low cost RFID tags. Multiple Cryptographic algorithms were proposed to insure the information security and in the same time respect the resource-constrained RFID systems (limited computational, storage capability...). In this paper, we proposed a hybrid encryption approach as symmetric key encryption that generate the key dynamically, together with integrity check factors. The key stream generation step follows the chained method, starting from the initial pre-shared key. The approach uses logical operations on intermediate cipher texts and intermediate Keys generated in each stage (named derive function), to generate successive keys. This is improving the chaining technique which use only cipher text to generate the successive keys. Finally, our approach will diminish the computational complexity as well as improve performance.

Cryptographic Algorithm Approach for Low Cost RFID Systems

Abstract: Today the security of RFID systems is a very important issue especially for low cost RFID tags. Then, it is difficult for several researchers to adopt a strong encryption algorithm due to the extremely limited computational, storage and communication abilities of the tag. So, the priority in RFID systems is to ensure the integrity, confidentiality and authentication of messages using different algorithms (such as encryption and hashing algorithm). In this paper, we propose a lightweight symmetric key encryption approach that includes integrity as part of the encryption process in order to meet the resource limitations of low cost RFID tags. Furthermore we do not need to use separate hash functions to verify message integrity, thus leading to increase the computational efficiency of the system.

Optimized Key Management System in Cryptographic algorithms for Data Security

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