: API key + digital signature (RSA) for high‑value transactions; OAuth2 for read‑only.
Vahan is the national vehicle registration database managed by the Ministry of Road Transport & Highways (MoRTH) , under NIC (National Informatics Centre) . Vahan 4.0 is the modernized, real-time, centralized version that replaced the older state‑wise, siloed systems. vahan 4
(conceptual):
POST /vahan4/api/vehicle/register Headers: X-API-Key, X-Signature Body: : API key + digital signature (RSA) for