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Smart Contracts Architecture

The Tokentagged protocol uses a modular architecture that combines maximum security via hardware-based crypto chips (EAL 6+) with decentralized verification.

High-Level Overview​

The system connects physical objects with the blockchain. At its core is the cryptographic verification of signatures generated directly on the NXP P71D321 chip.

The smart contracts act as "gatekeepers": a token (NFT) can only be minted if the physical chip cryptographically proves its authenticity and its authorization.

Architecture Diagram​

The following diagram shows how the contracts interact when a user scans and mints a Tokentag.

Contract Components​

ContractTypeDescription
TokentaggedAssetsCollectionThe public main collection (shared contract). Allows users to mint their Tokentags without deploying their own contract.
TokentaggedCollectionCollectionExclusive collections for brands or creators (whitelist-only). These contracts are owned by the creator.
TokentaggedAbstract CoreContains the bit-splitting logic for token IDs and the interface to hardware verification. Not deployed directly; inherited by collections.
TokentaggedSignerRegistrySecurityManages the "root of trust". Stores the manufacturer's public keys to validate chip authenticity (attestation).

Process Flow: Secure Minting​

This process shows how a token is created securely. Three signature layers are verified to ensure origin (manufacturer), integrity (card key), and authorization (user activation).