Pervasive computing environment is a distributed and mobile space. Trust relationship must be established and ensured between devices and the systems in the pervasive computing environment. The trusted computing （TC） technology introduced by trusted computing group is a distributed-system-wide approach to the provisions of integrity protection of resources. The TC＇s notion of trust and security can be described as conformed system behaviors of a platform environment such that the conformation can be attested to a remote challenger. In this paper the trust requirements in a pervasive/ubiquitous environment are analyzed. Then security schemes for the pervasive computing are proposed using primitives offered by TC technology.
The secure socket layer/ transport layer security（SSL/TLS） handshake protocol uses public key cryptographic algorithms such as RSA for key establishment. Typically, public key cryptographic algorithm is computational intensive due to the modular multiplications. Therefore, SSL/TLS servers often become swamped while performing public key decryptions when the simultaneous requests increase quickly. A batch RSA decryption algorithm was proposed. The novel algorithm provides the reasonable response time and optimizes server performance significantly. The decryption speedup is proportional to the batch size b, for instance, the speedup factor is 4, while in Shacham＇s scheme the acceleration rate is only 2.5 when b = 4.
Ising spin system has been shown to provide a new class of error-correction code and can be used to construct public-key cryptosystems by making use of statistical mechanics. The relation between Ising spin systems and private-key cryptosystems are investigated. Two private-key systems are based on two predetermined randomly constructed sparse matrices and rely on exploiting physical properties of the Mackay-Neal (MN) low-density parity-check (LDPC) error-correcting codes are proposed. One is error correcting private-key system, which is powerful to combat ciphertext errors in communications and computer systems. The other is a private-key system with authentication.
Quantum key agreement is one of the approaches to unconditional security. Since 1980’s, different protocols for quantum key agreement have been proposed and analyzed. A new quantum key agreement protocol was presented in 2004, and a detailed analysis to the protocol was given. The possible game played between legitimate users and the enemy was described: sitting in the middle, an adversary can play a “man-in-the-middle” attack to cheat the sender and receiver. The information leaked to the adversary is essential to the length of the final quantum secret key. It was shown how to determine the amount of information leaked to the enemy and the amount of uncertainty between the legitimate sender and receiver.
Verifiably encrypted signatures are employed when a signer wants to sign a message for a verifier but does not want the verifier to possess his signature on the message until some certain requirements of his are satisfied. This paper presented new verifiably encrypted signatures from bilinear pairings. The proposed signatures share the properties of simplicity and efficiency with existing verifiably encrypted signature schemes. To support the proposed scheme, it also exhibited security proofs that do not use random oracle assumption. For existential unforgeability, there exist tight security reductions from the proposed verifiably encrypted signature scheme to a strong but reasonable computational assumption.
