Some methods against spam are based on a principle that a recipient reads only messages from senders who are registered by the recipient (challenge and response). In these schemes, some exceptions are required to show error mail (bounce message) to a sender of an original message. However, spammers can abuse this exception to send spam to users. In this paper, we propose a new method which comb...

Use of encryption algorithms in message authentication is replaced by secure hash functions which are often faster than encryption algorithms. Tsudik 14] has proposed three methods on message authentication which are only based on one-way hash functions and use some keys to make them secure. In this paper, we give a set of practical methods, each of which uses a fast collision free hash functio...

This paper introduces approximate image message authentication codes (IMACs) for soft image authentication. The proposed approximate IMAC survives small to moderate image compression and it is capable of detecting and locating tampering. Techniques such as block averaging and smoothing, parallel approximate message authentication code (AMAC) computation, and image histogram enhancement are used...

The Secured communication protocol via encrypted key ensuring message integrity combination of Authentication of Third Party Authentication Quantum Key Distribute Protocol (implicit) and Third Party Authentication Quantum Key Distribute Protocol Mutual Authentication (explicit) quantum cryptography is used to provide authenticated secure communication between sender and Receiver. In quantum cry...

For objects stored in long-term digital archives, checking the integrity of the information stored is a prime necessity in the field of secure storage systems. Objects in a digital archive may include documents, images, databases, ..., etc. In a long-term archive those objects could be transferred in many various ways. In many cases, users are required to verify the authentication of the archiv...

The cryptographic literature contains many provably secure highspeed authenticators. Some authenticators use n multiplications for length-n messages; some authenticators have the advantage of using only about n/2 multiplications. Some authenticators use n variables for length-n messages; some authenticators have the advantage of using only 1 variable. This paper, after reviewing relevant polyno...

While standard message authentication codes (MACs) guarantee authenticity of messages, they do not, in general, guarantee the anonymity of the sender and recipient. For example it may be easy for an observer to determine whether or not two authenticated messages were sent by the same party even without any information about the secret key used. However preserving any uncertainty an attacker may...

Firewalls typically filter network traffic at several different layers. At application layer, filtering is based on various security relevant information encapsulated into protocol messages. The major obstacle for efficient verification of authenticity of messages at application layer is the difficulty of verifying digital signatures without disclosure of content protected by encryption. This i...

Traditional hash functions are designed to protect even a slightest modification in a message. Thus, one bit changed in a message would result in a totally different message digest when a hash function is applied. This feature is not suitable for applications whose message spaces admit some certain fuzziness such as multimedia communications or biometric authentication applications. In these ap...

Studies were conducted on vehicular ad-hoc network (VANET) in recent years. VANET is a network that combines on-board wireless equipment (On-Board Unit, OBU) and roadside fixed wireless equipment (Road Side Unit, RSU) through wireless communication technology. When vehicles broadcast messages, the traditional systems usually use RSU to do message authentication that we can ensure messages are i...