Simple authenticated key agreement and protected password change protocol

In this article, we shall present an authenticated key agreement protocol which is a modified and faster version of the Yeh-Sun scheme. Compared with the latest Kobara-Imai scheme, our scheme takes fewer steps and less computation cost. Besides, we shall also propose a protected password change protocol that allows users to change their own passwords freely. (c) 2005 Elsevier Ltd. All rights reserved