Abstract: A system is provided that allows users to execute a secure transaction that is authenticated by their user device. Personally identifiable information (PII), such as, but not limited to, biometric authentication data, is locally stored on the user's device so as to protect the PII. A user device private key is associated with the particular user device and the user, and the corresponding public key is registered with a User Device Authentication Alliance server (UDAAS) system. In an online transaction, a LoginID server or an Access Control server interact with the UDAAS to confirm the user is authentic and has confirmed the transaction.