An important problem in secure multi-party computation is the design of protocols that can tolerate adversaries that are capable of corrupting parties dynamically and learning their internal states. In this paper, we make significant progress in this area in the context of password-authenticated key exchange (PAKE) and oblivious transfer (OT) protocols. More precisely, we first revisit the noti...

The username/password paradigm is a well-known authentication mechanism. Probably the most common version in use is the password authentication via an HTML form. The user has to type his/her password directly into a web page from the site to which he/she wishes to authenticate himself/herself. The problem with using this approach is that it relies on the user to determine when it is safe to ent...

Password-authenticated key exchange (PAKE) allows two or multiple parties to share a session key using a human-memorable password only. PAKE has been applied in various environments, especially in the “clientserver” model of remotely accessed systems. Designing a secure PAKE scheme has been a challenging task because of the low entropy of password space and newly recognized attacks in the emerg...

Password Authenticated Key Exchange (PAKE) is a class of cryptographic protocols that allow two parties sharing a password to authenticate each other without explicitly revealing the password in the process. PAKE protocols offer a potential improvement over current web authentication practices, e.g., HTML form-based password authentication, but there has been little progress towards integrating...

The password-authenticated key exchange (PAKE) is an important tool to secure wireless communications. To counter possible malicious attacks in wireless communications, this paper develops a stronger new cross-realm client-to-client (C2C) PAKE protocol based on the smart card framework agreement. Employing the client passwords, smart card information and server private keys, the new PAKE protoc...

A threshold password-authenticated key exchange (T-PAKE) protocol allows a set of n servers to collectively authenticate a client with a human-memorizable password such that any subset of size greater than a threshold t can authenticate the client, while smaller subsets of servers learn no information about the password. With its protection against offline dictionary attacks, T-PAKE provides a ...

Secure two-party authentication and key exchange are fundamental problems. Traditionally, the parties authenticate each other by means of their identities, using a public-key infrastucture (PKI). However, this is not always feasible or desirable: an appropriate PKI may not be available, or the parties may want to remain anonymous, and not reveal their identities. To address these needs, we intr...

Although two-party password-authenticated key exchange (PAKE) protocols have been intensively studied in recent years, group PAKE protocols have received little attention. In this paper, we propose a hierarchical group PAKE protocol nPAKE protocol under the setting where each party shares an independent password with a trusted server. The nPAKE protocol is a novel combination of the hierarchica...

We introduce a novel notion of smooth (-verifier) noninteractive zero-knowledge proofs (NIZK) which parallel the familiar notion of smooth projective hash functions (SPHF). We also show that the recent single group element quasi-adaptive NIZK (QA-NIZK) of Jutla and Roy (CRYPTO 2014) for linear subspaces can be easily extended to be computationally smooth. One important distinction of the new no...

Secure Remote Password (SRP) protocol is an augmented Password-based Authenticated Key Exchange (PAKE) protocol based on discrete logarithm problem (DLP) with various attractive security features. Compared with basic PAKE protocols, SRP does not require server to store user’s password and user does not send password to server to authenticate. These features are desirable for secure client-serve...