With some properties of bilinear pairings, there have been active researches in cryptography.Recently, Das et al. proposed a novel remote user authentication scheme using bilinear pairings over elliptic curve. However, it does not agree with multi-server environment. In this paper, we propose a password authentication scheme based on bilinear pairings for multi-serve environment. Not only does our scheme achieve the efficient computation requirement for smart cards, but also it can construct a complete authentication scheme, including mutual authentication and session key agreement. Our scheme uses nonce instead of timestamp to withstand relay attacks. In addition, the remote server requires nothing about the secret key of the key distribution center (KDC) to authenticate the users. Our scheme also analyzes the security and compares the functionality with other schemes.
