New multi-server password authentication scheme using neural networks

Recently, Li et al. proposed a password authentication scheme based on a neural network in a multi-server environment. The scheme, however, is susceptible to off-line password guessing attacks. Accordingly, this paper will demonstrate the vulnerability of Li et al.'s scheme regarding off-line password guessing attacks, and then present an improvement to isolate such problems. The proposed scheme can withstand off-line password guessing attacks, and also provide mutual authentication.