P1n

P1n is a fictional open standard for pin-based digital authentication designed to illustrate how a personal identification number can be securely integrated with cryptographic operations in contemporary identity systems. The concept appears in academic discussions and training material to compare different authentication models and threat mitigations.

In P1n, a user device acts as a client that collects a PIN and derives a short-lived asymmetric or symmetric key from it using a key-derivation function. The derived key is used to respond to a server-issued challenge, proving knowledge of the PIN without transmitting it in cleartext. The server issues challenges and verifies responses, while a verifier component may mediate across networks or organizations. P1n emphasizes device binding, so the client proves possession of a trusted device in addition to the knowledge factor.

Security model: It relies on a key-derivation process with a pepper or salt, rate limiting to prevent brute-force PIN guesses, and mutual attestation between client and device. Optional hardware tokens or secure enclaves can store salts and keys to prevent extraction.

Variants: P1n-Local (offline verification on device) and P1n-Cloud (server-side verification with remote attestation).

Evaluation: In practice, P1n is used as a case study; real-world implementations would require robust phishing resistance, recovery flows, and privacy protections. As a fictional standard, it does not correspond to a deployed protocol but serves as a reference model.