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Beware of alleged "military grade secure" products. It is one thing to use AES-256 or RSA-4096, using it correctly is a different kettle of fish.
We can help you build innovative products that require any standard or advanced cryptographic tools, such as elliptic curves, identity-based encryption, anonymous signatures, e-cash, DRM, Pay-TV and many others.

Related technology

Pay-TV & Content Protection

The new encryption technology for content distribution.

STONE is the industry’s first efficient cryptographic solution that enables CAS vendors and content providers to identify and remotely disable compromised smart cards used by pirate emulators. A smart card implementation of STONE is in preparation.


Related services

Cryptographic Product Review

A fresh pair of eyes on your design.

The development of a cryptographic product, from a protocol on a whiteboard to an industrial grade implementation, is a long and complex process. Our experts will help you avoid common (and less common) pitfalls at any stage of the development.


Post-Quantum Cryptography

You are not prepared.

One day, quantum computers will become a reality. When that day comes, RSA, Elliptic Curves and many other fundamental cryptographic primitives will become obsolete. Post-Quantum Cryptography offers secure alternatives and we can help you get ready.


Random Number Generation

Good random number generation is not a matter of chance!

Random Number Generation (RNG) is the cornerstone primitive for most security applications. The design of Random Number Generators, whether hardware-based or fully software, is at the core of our expertise.


Related research projects


Towards trustworthy and privacy-respecting authentication.

ABC4Trust is an EU-funded research initiative that uses cryptographic technologies to provide better protection of privacy and identity on the Internet.



Innovative and cost-effective broadcast encryption for pay TV and Galileo geo-positionning.

Innovative techniques to securely broadcast content to large groups of users over an insecure channel with applications to pay TV, wireless networks, military radio communications and Galileo.



The best of cryptographic science for the embedded security marketplace.

Lightweight block ciphers are cost-effective solutions for symmetric encryption on embedded systems such as RFIDs and smartcards. They are specifically designed to fit in low-cost devices with very efficient hardware modules in terms number of gates, area, memory and speed. However one has to make sure that the lightweight design does not open the door to security flaws, this being guaranteed through built-in provable security.



Boosting Elliptic Curves in the Embedded World.

Many business cases and user experiences could be improved or made more profitable if specific ECC-supporting hardware existed that would speedup security protocols by an order of magnitude at minimal cost. The main purpose of Eclipses is to accelerate progress towards such hardware solutions and subsequently boost low-cost public-key and pairing-based cryptography in embedded secure applications.



The Smart Cloud approach: database-supporting smartcards securely operated through the Cloud.

The KISS research initiative introduces the concept of Smart Cloud, whereby end users carry secure tokens managing their personal data instead of relying on cloud storage. Through a variety of innovative cryptographic technologies, a Smart Cloud also supports data federation and aggregation such as statistics, but in a built-in, privacy-respecting way.



Protecting user privacy on NFC-enabled mobile phones.

A personal data breach may, if left unaddressed in an adequate and timely manner, result in a substantial economy loss and social harm. A breach should be considered as adversely affecting the data or privacy of a subscriber or service user when it can result in, for example, a confidentiality breach, discrimination, unwanted exposure, loss of control, unauthorized commercial solicitations or damage to reputation. Innovative crypto can help.



Exploring the reverse-engineering taboo.

The goal of the MARSHAL project is to design and realize a mobile security object that withstands all known reverse-engineering attacks by means of software and hardware countermeasures.



The mission of the MATTHEW project is to enable new applications and services on mobile devices. It will overcome the limitation of current passive NFC transmission technologies by active modulation and offer new ways of exchanging roles from one mobile platform, like a smartphone or tablet, to another.


Countless security products advocate the use of highly secure cryptographic algorithms, such as AES-256 or Curve25519. Saying so only disclose the tip of the iceberg. Indeed, one should wonder how those algorithms are actually used within the product. This is what cryptographic protocols are all about.

Cryptographic protocols are hard to get right

Designing a cryptographic protocol correctly is a hard task, and even cryptographic standard may be flawed. For example, the ISO/IEC 9798 standard for entity authentication has been revised many times due to the discovery of several weaknesses. But things can get even worse: assume your product requires two distinct protocols. Assume you choose two secure protocols. Are you safe? Not necessarily. The reason is that composing secure protocols does not necessarily lead to a secure system.

Changing a protocol along the way is painful

By nature, cryptographic protocols are at the heart of the products that make use of them. Changing protocol during the lifetime of a product is a very painful thing to do, inevitably causing loss in terms of customer trust.

Your product should use the right protocol, right from the start.

We can help

Do you have a concrete use-case? Are you building an innovative product that requires a secure cryptographic protocol but lack the required expertise? We can design the custom cryptographic protocol that best suits your requirements. Here is a list of some use cases we have encountered in the past:

  • Privacy-preserving access control protocols
  • Privacy-preserving e-ticketing schemes
  • Anonymous credential systems
  • Broadcast encryption schemes with traitor tracing capabilities for Pay-TV
  • Digital Right Management (DRM) systems with inherently supported features such as the identification of compromised keys
  • Identity-based encryption and signature schemes (a PKI-free cryptographic technology for corporate security applications)
  • Electronic voting (e-voting) schemes with provably secure features
  • Electronic cash (e-cash) systems with provably secure online/offline withdraw, spending and transfer protocols

Whenever possible, our security solutions come with appropriate cryptographic security proofs that can serve as a basis for security certification schemes (Common Criteria, FIPS, BSI, ANSSI, etc.) and submissions to standardization organizations (ISO/IEC, CEN, ETSI, etc).

Why choose us

We are worldwide experts in cryptography. All the members of the design team have a PhD. in cryptography and many years of industrial experience. Our cryptographic protocols are not only secure: they can fit your environment.

Related publications

  • 🇫🇷 Quatre millions d'échanges de clés par seconde.
    Carlos Aguilar-Melchor, Serge Guelton, Adrien Guinet, Tancrède Lepoint.
    In SSTIC 2015, 2015.
  • Integrating Anonymous Credentials with eIDs for Privacy-Respecting Online Authentication.
    Ronny Bjones, Ioannis Krontiris, portrait ofPascal Paillier, Kai Rannenberg.
    In APF 2012, pp. 111-124, 2012.
  • SPAKE: A Single-Party Public-Key Authenticated Key Exchange Protocol for Contact-Less Applications.
    Jean-Sébastien Coron, Aline Gouget, portrait ofPascal Paillier, Karine Villegas.
    In Financial Cryptography Workshops 2010, pp. 107-122, 2010.
  • Dynamic Threshold Public-Key Encryption.
    Cécile Delerablée, David Pointcheval.
    In CRYPTO 2008, pp. 317-334, 2008.
  • Fully Collusion Secure Dynamic Broadcast Encryption with Constant-Size Ciphertexts or Decryption Keys.
    Cécile Delerablée, portrait ofPascal Paillier, David Pointcheval.
    In Pairing 2007, pp. 39-59, 2007.
  • Decryptable Searchable Encryption.
    Thomas Fuhr, portrait ofPascal Paillier.
    In ProvSec 2007, pp. 228-236, 2007.