Billions of people now have conversations daily over the Internet. A large portion of this communication takes place via secure messaging protocols that offer "end-to-end encryption'" guarantees and resilience to compromise like the widely-used Double Ratc ...
Succinct zero knowledge proofs (i.e. zkSNARKs) are powerful cryptographic tools that enable a prover to convince a verifier that a given statement is true without revealing any additional information. Their attractive privacy properties have led to much ac ...
Homomorphic Encryption (HE) enables computations to be executed directly on encrypted data. As such, it is an auspicious solution for protecting the confidentiality of sensitive data without impeding its usability.
However, HE does not provide any guarant ...
Secure retrieval of data requires integrity, confidentially, transparency, and metadata-privacy of the process. Existing protection mechanisms, however, provide only partially these properties: encryption schemes still expose cleartext metadata, protocols ...
Bluetooth (BR/EDR) is a pervasive technology for wireless communication used by billions of devices. The Bluetooth standard includes a legacy authentication procedure and a secure authentication procedure, allowing devices to authenticate to each other usi ...
Following up mass surveillance and privacy issues, modern secure communication protocols now seek more security such as forward secrecy and post-compromise security. They cannot rely on an assumption such as synchronization, predictable sender/receiver rol ...
In our daily lives, people or devices frequently need to learn their location for many reasons as some services depend on the absolute location or the proximity. The outcomes of positioning systems can have critical effects e.g., on military, emergency. Th ...
An active distribution network (ADN) is an electrical-power distribution network that implements a real-time monitoring and control of the electrical resources and the grid. Effective monitoring and control is realised by deploying a large number of sensin ...
We show how any pair of authenticated users can on-the-fly agree on an elliptic curve group that is unique to their communication session, unpredictable to outside observers, and secure against known attacks. Our proposal is suitable for deployment on cons ...
This PhD thesis is concerned with authentication protocols using portable lightweight devices such as RFID tags. these devices have lately gained a significant attention for the diversity of the applications that could benefit form their features, ranging ...
We consider the problem of securely conducting a poll in synchronous dynamic networks equipped with a Public Key Infrastructure (PKI). Whereas previous distributed solutions had a communication cost of O(n^2) in an n nodes system, we present SPP (Secure an ...
The ARMADILLO cryptographic primitive is a multi-purpose cryptographic primitive for RFID devices proposed at CHES’10. The main purpose of the primitive is to provide a secure authentication in a challenge-response protocol. It has two versions, named ARMA ...
We present a cryptographically t-private protocol for electronic auctions whose low resource demands make it viable for practical use. Our construction is based on Yao's garbled circuits and pseudorandom number generators (PRNGs). Our protocol involves a f ...
Our main motivation is to design more user-friendly security protocols. Indeed, if the use of the protocol is tedious, most users will not behave correctly and, consequently, security issues occur. An example is the actual behavior of a user in front of an ...
In RFID protocols, tags identify and authenticate themselves to readers. At Asiacrypt 2007, Vaudenay studied security and privacy models for these protocols. We extend this model to protocols which offer reader authentication to tags. Whenever corruption i ...
New trends in consumer electronics have created a strong demand for fast, reliable and user-friendly key agreement protocols. However, many key agreement protocols are secure only against passive attacks. Therefore, message authentication is often unavoida ...
Books, videos, music, still images and any other type of media information, share a number of features that enable their migration from traditional delivery technologies to an all-electronic delivery model. They can easily be digitized, stored, compressed ...