Composable, Unconditionally Secure Message Authentication without any Secret Key
This provides a composable, unconditionally secure authentication solution for communication systems, addressing a foundational challenge in information theory.
The paper tackles the problem of achieving both error correction and authentication without a shared secret key, demonstrating that Bob can decode messages from Alice and reject those from Eve with high probability under a less noisy channel condition.
We consider a setup in which the channel from Alice to Bob is less noisy than the channel from Eve to Bob. We show that there exist encoding and decoding which accomplish error correction and authentication simultaneously; that is, Bob is able to correctly decode a message coming from Alice and reject a message coming from Eve with high probability. The system does not require any secret key shared between Alice and Bob, provides information theoretic security, and can safely be composed with other protocols in an arbitrary context.