Abstract: In [3] Al-Riyami and Paterson introduced the notion of “Certificateless Public Key Cryptography” and presented an instantiation. In this paper, we revisit the formulation of certificateless public key encryption and construct a more efficient scheme and then extend it to an authenticated encryption.

Abstract: Nyberg and Ruppel first proposed a signature scheme with message recovery based on DSA in 1993, and the authenticated encryption scheme is a special application of their scheme. Afterward, there are many papers proposed about the authenticated encryption schemes. The signature scheme can reduce the transmitted cost, because the message has been contained in the signature of the message and the signer does not necessary to send the receiver the message and the signature. The scheme is very suitable for the key agreement application, because a key is a small amount of a message. In order to comprehend and interpret the authenticated encryption schemes overall, we discuss the evolution and the existed problems of authenticated encryption schemes.

Abstract: This paper is primarily concerned with the CBC block cipher mode. The impact on the usability of this mode of recently proposed padding oracle attacks, together with other related attacks described in this paper, is considered. For applications where unauthenticated encryption is required, the use of CBC mode is compared with its major symmetric rival, namely the stream cipher. It is argued that, where possible, authenticated encryption should be used, and, where this is not possible, a stream cipher would appear to be a superior choice. This raises a major question mark over the future use of CBC mode, except as part of a more complex mode designed to provide authenticated encryption.

Abstract: An encrypted data distributing method includes preparing cipher text which can be decrypted only by a specific trusted device, and performing encryption and decryption processing at a high speed. An encryption key is prepared using an encryption device authentication key unique to an encryption device and a decryption device authentication key unique to a decryption device, and cipher text is prepared by this encryption key. The authentication keys are also sent to the decryption device. In the decryption device, the decryption device authentication key received from the encryption device is compared with the decryption device authentication key prepared by the decryption device to perform decryption processing only when the authentication keys match.

Abstract: An authenticated encryption scheme allows messages to be encrypted and authenticated simultaneously. In 2003, Ma and Chen proposed such a scheme with public verifiability. That is, in their scheme the receiver can efficiently prove to a third party that a message is indeed originated from a specific sender. In this paper, we first identify two security weaknesses in the Ma-Chen authenticated encryption scheme. Then, based on the Schnorr signature, we proposed an efficient and secure improved scheme such that all the desired security requirements are satisfied.

Abstract: This paper proposes a new public key authenticated encryption (signcryption) scheme based on the hardness of q-Diffie-Hellman problems in Cap Diffie-Hellman groups, This new scheme is quite efficient: the signcryption operation has almost the same cost as an El Carnal encryption while the reverse operation only requires one pairing evaluation and three exponentiations. The scheme's chosen-ciphertext security is shown to be related to the hardness of the q-Diffie-Hellman Inversion (q-DHI) problem in the random oracle model while its unforgeability is proved under the q-Strong Diffie-Hellman assumption (q-SDH). It also provides detachable signatures that are unlinkable to the original anonymous ciphertext. We also show that most of the sender's workload can be computed offline. Our construction is based on a signature scheme independently studied by Boneh-Boyen and Zhang et al. in 2004.

Abstract: In this study, an authenticated encryption scheme with public verifiability and message linkages is proposed. The new scheme requires smaller bandwidth and computational time as compared to previously proposed authenticated encryption schemes with message linkages. Furthermore, if the signer repudiates the signature, the recipient can prove the dishonesty of the signer to any verifier without disclosing the message by converting this signature into an ordinary one single.

Abstract: In this paper, the link security module developed by draft standard of IEEE 802.1AE in order to protect all frames from a listening or attacking of a malicious user at an EPON link. And it applied at an EPON OLT (optical line terminal)/ONU (optical network unit) and is provided a link security about the maximum 64 ONUs. It also used a 128 bits GCM-AES (Galois/counter mode-advanced encryption standard) of an authenticated encryption mode that was mandatory-to-implement crypto- algorithm in draft standard. So, link security module can provide the user data confidentiality and frame data integrity, and data origin authenticity to subscribers, and support a link security at the maximum 2 Gbps EPON using the parallel CTR-AES (counter-AES) in the GCM-AES

Abstract: Ring authenticated encryption has the following security requirements: semantic-security, recipient-designation, verification-dependence, verification-convertibility, recipient-ambiguity, recipient-verifiability, signer-ambiguity and signer-verifiability. Ring authenticated encryption can be used to enhance user privacy. In this paper, based on Boneh and Frankliny's ID-based encryption scheme and Zhang and Kim's ID-based ring signature scheme, we propose an ID-based ring authenticated encryption scheme. We also show that the proposed scheme satisfies the correctness property and all security requirements.

Abstract: SOBER-128 is a stream cipher designed by Rose and Hawkes in 2003. It can be also used for generating Message Authentication Codes (MACs) and an authenticated encryption. The developers claimed that it is diffcult to forge MACs generated by both functions of SOBER-128, though, the security assumption in the proposal paper is not realistic in some instances. In this paper, we examine the security of these message authentication mechanisms of SOBER-128 under security channel model. As a result, we show that both a MAC generation and an authenticated encryption are vulnerable against differential cryptanalysis. The success probabilities of the MAC forgery attack are estimated at 2-6 and 2-27 respectively. In addition, we show that some secret bits are revealed if a key is used many times.

Abstract: In 2003, Tseng et al. proposed a self-certified public key signature with message recovery, which gives two advantages: one is that the signer's public key can simultaneously be authenticated in verifying the signature and the other one is that only the specified verifier can recover the message. Lately, Xie and YU proposed an attack to the Tseng et al.'s scheme under the cases: the specified verifier substitutes his secret key or two or more specified verifiers cooperatively forge the signer's signature. About the same time, Shao also proposed another insider forgery attack to break the Tseng et al.'s scheme. In addition, he claimed the Tseng et al.'s scheme without the properties of non-repudiation and forward security. Therefore, he proposed an improved scheme to overcome the weakness. In this paper, we will show that the Shao's improved scheme is still insecure against the insider forgery attack. A specified verifier can forge many different valid signatures with the same message to the other verifiers who cooperatively provide their secret keys. Furthermore, we give a small modification to overcome this weakness.

Abstract: An authenticated encryption scheme is a message transmission scheme, which sends messages in a secure and authentic way. In large message transmission, traditional authenticated encryption scheme has the disadvantage that the communication and the computation costs are too high. In 2002, Tseng-Jan proposed an efficient authenticated encryption scheme with messages linkage; that is, only a random number was used and the communication costs and the computational complexity were better than previously proposed schemes. The current paper, however, points out that Tseng-Jan's scheme suffers from serious security faults such that any adversary can easily forge valid signature blocks and pass the receiver's verification, and the scheme does not provide forward secrecy and non-repudiation. We also propose an improvement to the scheme to overcome the weaknesses.

Abstract: We address authenticated encryption, the cryptographic technique that simultaneously provides both confidentiality and authenticity, and steganography that hides the very existence of messages. We focus on the security of these techniques against adversaries with unbounded computational resources. First, we reveal the strong security notion of unconditionally secure authenticated encryption and show how to achieve it. Second, we study unconditionally secure stegosystems under active attacks and show how to construct them by the above mentioned unconditionally secure authenticated encryption schemes

Abstract: An authenticated encryption scheme is a message transmission scheme, which sends messages in a secure and authentic way. In large message transmission, traditional authenticated encryption scheme has the disadvantage that the communication and the computation costs are too high. In 2002, Tseng-Jan proposed an efficient authenticated encryption scheme with messages linkage; that is, only a random number was used and the communication costs and the computational complexity were better than previously proposed schemes. The current paper, however, points out that Tseng-Jan's scheme suffers from serious security faults such that any adversary can easily forge valid signature blocks and pass the receiver's verification, and the scheme does not provide forward secrecy and non-repudiation. We also propose an improvement to the scheme to overcome the weaknesses.

Abstract: Recent progress in nanotechnology has focused on applying nanoscale phenomenon in physical layer or device level applications. In this paper, we show that nanoscale phenomenon cannot only be used in physical layer, but also in high layer application such as communication protocols. In this paper, we study the possibility of performing authentication and encryption based on quantum entanglement, which is a phenomenon available only at the nanoscale level. Unlike classical authentication and encryption algorithms, the security of this protocol is based on nanoscale physical laws, instead of any unproven mathematic conjecture.

Abstract: In accordance with the present invention, computer implemented methods and systems are provided for converting an elastic block cipher from an original block cipher. The elastic block cipher accepts variable length inputs where the computation workload increases in proportion to the block size. To generate the elastic block cipher, the number of rounds in the block cipher is increased such that the round function is applied to each bit position at least the same number of times as the original block cipher. In addition, bits that are beyond the normal block size are left out of the round function and XORed and swapped with bits output from the round function to become part of the input to the next round.

Abstract: The method of parameter choice in signature equation is proposed based on primarily its characteristics, almost including different forms of parameters in this kind of signature equation Homeostasis attack of this kind of scheme is also proposed with known plaintext, all of these could make up the shortcoming of theory analysis

Abstract: In the most present authenticated encryption schemes the recipient cannot prove the signer's dishonesty to any verifier if the signer denies the signature To overcome this problem, Ma-Chen proposed an efficient authenticated encryption scheme with public verifiability In this paper it was demonstrated that their scheme cannot resist the special forgery attack about the one-way Hash function, ie, a dishonest recipient can easily forge valid signatures for any messages on behalf of the signer To solve the above weakness, based on the Discrete Logarithm Problem,a secure improved scheme was proposedThis scheme can satisfy all the desired security requirements Further, the proposed scheme is more efficient than Ma-Chen's in terms of the computation cost

Abstract: Based on the factorization problem, a modified (t, n) threshold group-oriented scheme with message recovery is proposed. In the proposed scheme, any combination of more than t members of the group can cooperate to generate the modified group secret key. By using the proposed scheme, the transmission of the signature is secure. Besides, the message linkage blocks which are removed by an eavesdropper can be detected.