How to pay without internet using central bank digital currency?

Imagine being able to pay with central bank digital currency (CBDC) even without an internet connection. Sounds like a dream? Not anymore! A new study proposes a secure offline payment model using a trusted platform module (TPM). This small chip, already present in many devices, helps secure transactions and prevent double spending. The secret? A monotonic counter that keeps track of transactions. Sure, there are challenges to face, like the security of TPMs and near-field communications, but the road to offline digital payments has just begun!

The Trusted Platform Module (TPM) is a hardware security chip that provides cryptographic functions to protect data and transactions. In this study, the TPM is used to ensure that CBDC transactions are secure even without an internet connection. The monotonic counter, a key component of the TPM, increments with each transaction, preventing the same CBDC from being spent more than once. This mechanism is crucial for maintaining the integrity of transactions in an offline environment. However, it is important to consider the potential vulnerabilities of TPMs and near-field communications, which could be exploited by malicious actors.