ID-Based Group Password-Authenticated Key Exchange

Group Password-Authenticated Key Exchange from Identity-Based Cryptosystem

Password-authenticated key exchange (PAKE) protocols are designed to be secure even when the secret key used for authentication is a human-memorable password. In this paper, we consider PAKE protocols in the group scenario, in which a group of clients, each of them shares a password with an “honest but curious” server, intend to establish a common secret key (i.e., a group key) with the help of...

Password Based Key Exchange with Hidden Elliptic Curve Public Parameters

We here describe a new Password-based Authenticated Key Exchange (PAKE) protocol based on elliptic curve cryptography. We prove it secure in the Bellare-Pointcheval-Rogaway (BPR) model. A significant novelty in our work is that our proposal is conceived in a such a way that it ensures that the elliptic curve public parameters remain private. This is important in the context of ID contactless de...

Authenticated ID-based Key Exchange and Remote Log-in with Insecure Token and PIN Number

New Anonymity Notions for Identity-Based Encryption

Identity-based encryption is a very convenient tool to avoid key management. Recipient-privacy is also a major concern nowadays. To combine both, anonymous identity-based encryption has been proposed. This paper extends this notion to stronger adversaries (the authority itself). We discuss this new notion, together with a new kind of non-malleability with respect to the identity, for several ex...

Authenticated ID-based Key Exchange and remote log-in with simple token and PIN number

Authenticated key exchange protocols tend to be either token based or password based. Token based schemes are often based on expensive (and irreplaceable) smart-card tokens, while password-only schemes require that a unique password is shared between every pair of correspondents. The magnetic strip swipe card and associated PIN number is a familiar and convenient format that motivates a combine...