Contextual biometric-based authentication for ubiquitous services

We introduce and comment on the concept of contextual pseudo identity. A contextual pseudo identity is a soft identity token that is built from both a user's biometric and the context. When it comes to ubiquitous authentication, a contextual pseudo identity promises better security than that o ered by traditional biometrics-based identity tokens: the use of context improves the tokens' disposability and renewability, which are two essential properties in the protection of a user's real identity. Our algorithm for generating contextual pseudo identities extends a Fuzzy Embedder so that it accepts both biometric and context dependent input. We prove that our way of processing the context preserves the security and reliability properties of the Fuzzy Embedder used in our extension. An example shows how a user can utilize contextual pseudo identity to authenticate to and access ubiquitous services.