Pairings permit several protocol simplications and original scheme creation, for example Identity Based Cryptography protocols. Initially, the use of pairings did not involve any secret entry, consequently, side channel attacks were not a threat for pairing based cryptography. On the contrary, in an Identity Based Cryptographic protocol, one of the two entries to the pairing is secret. Side Cha...

In this paper, we propose a generic method to construct Hierarchical Identity-Based Signcryption scheme. Using this method, a Hierarchical Identity-Based Signcryption scheme can be converted from any Hierarchical Identity-Based Encryption scheme. Then, we give a concrete instantiation, which is the first constant-size fully secure hierarchical identity-based signcryption scheme in the standard ...

Wireless sensor networks are being deployed for a wide variety of applications. It is an important challenge to find out practical security protocols for wireless sensor networks due to limitation of power, computation and storage resources. Symmetric key techniques are attractive due to their energy efficiency. But the drawbacks of symmetric key techniques are evident in terms of key managemen...

In identity-based public-key cryptography, an entity’s public key can be easily derived from its identity. The direct derivation of public keys in identity-based public-key cryptography eliminates the need for certificates and solves certain public key management problems in traditional public-key cryptosystems. Recently, the notion of asymmetric group key agreement was introduced, in which the...

How to deal with large tightness gaps in security proofs is a vexing issue in cryptography. Even when analyzing protocols that are of practical importance, leading researchers often fail to treat this question with the seriousness that it deserves. We discuss nontightness in connection with complexity leveraging, HMAC, lattice-based cryptography, identity-based encryption, and hybrid encryption.

Dependence on a public key infrastructure (PKI) is the prominent obstructer in the path of following a public key cryptography widespread, which is held together among various users. In order to ensure authenticated communication, encryption and signature key pair must be generated by each senders and receivers. Apart from this, request along with the proof of identity should also be submitted ...

The traditional identity-based cryptography requires a user, who holds multiple identities, to hold multiple private keys, where each private key is associated with an identity. Managing multiple private/public keys is a heavy burden to a user due to key management and storage. The recent advancement of identity-based cryptography allow a single private key to map multiple public keys (identiti...

In a fuzzy identity-based encryption (IBE) scheme, a user with the secret key for an identity ID is able to decrypt a ciphertext encrypted with another identity ID′ if and only if ID and ID′ are within a certain distance of each other as judged by some metric. Fuzzy IBE also allows to encrypt a document to all users that have a certain set of attributes. In 2005, Sahai and Waters first proposed...