Sfd Token Generator -

A validator checks:

"denom": 100, // 100 cents = $1 "id": "a3f5c2b1e8d4", "state": 0, // 0=unspent,1=spent "sig": h'9a3b...' // 64-byte signature sfd token generator

Existing token minting methods either allow unlimited divisibility (risking inflation) or rely on centralized databases (single point of failure). No standardized generator exists for creating secure, non-divisible tokens that can be verified offline. This paper formalizes the SFD token generator. A validator checks: "denom": 100, // 100 cents

[6] National Institute of Standards and Technology. "FIPS 186-5: Digital Signature Standard." 2023. [6] National Institute of Standards and Technology

| Threat | Mitigation via SFD Tokens | |--------|---------------------------| | | Tokens are short‑lived; even if intercepted, they quickly become useless. | | Replay attacks | The nonce field + optional replay cache prevents reuse within the token’s validity window. | | Man‑in‑the‑middle tampering | HMAC/RSA signatures detect any alteration; TLS protects token in transit. | | Key compromise | Rotate keys regularly (e.g., daily) and support key‑id ( kid ) in the header for smooth rollover. | | Privilege escalation | Payload explicitly lists the allowed object and operation; the verifier enforces exact matching. | | Denial‑of‑service (token flood) | Rate‑limit token‑generation endpoints; use CAPTCHAs or client‑certificate authentication for public APIs. |