Securing payments and identity in the post-quantum era

Bruno Sanglé-Ferrière, founder of Carrousel Digital, created Moneytak: a technology that makes secure payments and identity management possible, even without connection. A decisive step towards safe and universally accessible digital.

Can you give us an overview of the apps Moneytak E-cash and Moneytak ID-Papers?

The Moneytak e-Cash is a prepaid payment application that uses NFC technology to allow free money transfers, even offline, without the need to be connected to a verification server. Its post-quantum security offers a robust solution for prepaid cards, e-cash and vouchers.

The Moneytak ID-Papers, meanwhile, is designed for secure management and transmission of authenticated documents. This service guarantees the authenticity of documents, allowing users to store and show identity papers and other important documents in a secure way, online or offline. It is particularly practical for remote identity verification, such as on websites, thus ensuring maximum protection of information, but is especially important for verifying the authenticity of papers offline, through NFC contact between phones.

Both applications use a ‘Random hash’ signature, a process patented by Mr Sanglé-Ferrière that uses one-time keys to encrypt digital signatures. This process has two advantages, it is quantum safe as it is not using and encryption function, and it can use very small keys, such as 25bit keys as the only chance to fake such signature would be to guess it. This small size enables its use in peer-to-peer offline authentication as entire populations such as the one of the UK can share keys , using only a few Giga bytes of memory, while traditional systems would require between 5 and 400 times that amount, and still not be quantum safe.

What are the benefits and implications of Moneytak E-cash for users?

The device allows transactions without requiring an internet connection, and offers users the possibility to manage their money directly from their mobile devices when they are online. Even in the absence of a connection, the application preserves the transaction history, thus ensuring the security and integrity of all operations once the connection is restored, to fight against any form of hacking.

Thanks to advanced cryptography and random hash signatures, transactions are protected against potential threats from quantum computers. Each device has unique keys, limiting the impact of a potential security issue. Users can receive money, pay other owners of the application, even in areas without Internet, by simply moving their phone closer to that of another user or remotely using a web connection but without necessarily having to use a server.

What are the use cases and advantages of Moneytak ID-Papers?

Moneytak ID-Papers stands out for its ability to manage documents in a secure and authenticated way, even offline. Thanks to post-quantum security, it ensures that the verification of document authenticity cannot be bypassed and limits the impact of an unlikely security issue to a single device.

When used online, the web site of server that uses the Moneytak app for client verification will make sure that its correspondent has his unduplicable ID with him, on his phone and will be able to do a face match between the picture on the ID and the user of the phone.

When used offline, a party that wants to check the identity of someone will ask him to send him, through an NFC tap, a copy of the document.   Not only the received ID will be genuine, but a face match between the picture on the ID and the person in front will be implementable.

The benefits for users are numerous, especially in contexts where information security is crucial. Digital documents enable accurate verification and are equipped with advanced security features, reducing the risk of identity theft and financial fraud. Unlike paper documents, which are more prone to these risks, Moneytak ID-Papers also offers a reliable solution for remote and nearby identity verification, ensuring maximum security of personal information.