We revisit the problem of " sending information into the future " by proposing an anonymous, non-interactive, server-based Timed-Release Encryp-tion (TRE) protocol. We improve upon recent approaches by Blake and Chan, Hwang et al., and Cathalo et al., by reducing the number of bilinear pairings that users must compute, and by enabling additional… (More)
We propose a new Timed Release Cryptography (TRC) scheme which is based on bilinear pairings together with an S/Key-like procedure used for private key generation. Existing schemes for this task, such as time-lock puzzle approach, provide an approximate release time, dependent on the recipients' CPU speed and the beginning time of the decryption process.… (More)
Key establishment protocols are among the most important security mechanisms via which two or more parties can encrypt their communications over an insecure network. This paper is concerned with the vulnerability of one-pass two-party key establishment protocols to key-compromise impersonation (K-CI) attacks. The latter may occur once an adversary has… (More)
The vast majority of computer and communication systems use passwords in order to identify users. Unfortunately, in ubiquitous alphanumeric password schemes, users tend to choose passwords with predictable characteristics, related to how easy they are to remember. To overcome the vulnerabilities of textual passwords, a lot of alternative techniques have… (More)
For two parties to communicate securely over an insecure channel, they must be able to authenticate one another and establish a common session key. We propose a new secure one-pass authenticated key establishment protocol which is well suited to one-way communication channels. The protocol is examined using an extension of the Bellare-Rogaway model proposed… (More)
Key establishment protocols are among the most important security mechanisms via which two or more parties can generate a common session key to in order to encrypt their communications over an otherwise insecure network. This paper is concerned with the vulnerability of one-pass two-party key establishment protocols to key-compromise impersonation (K-CI)… (More)
We discuss a recently proposed one-pass authenticated key agreement protocol, and Lo, which was " derived " from their correponding two-pass version and claimed to be secure. We show that this is not the case by demonstrating a number of vulnerabilities.