Supporting user mobility is one of the most challenging issues in wireless networks. Recently, as the desires for the user mobility and high-quality multimedia services increase, fast handoff among base stations comes to a center of quality of connections. Therefore, minimizing re-authentication latency during handoff is crucial for supporting various promising real-time applications such as Voice over IP (VoIP) on public wireless networks. In this study, we propose an enhanced proactive key distribution scheme for fast and secure handoff based on IEEE 802.11i authentication mechanism. The proposed scheme reduces the handoff delay by reducing 4-way handshake to 2-way handshake between an access point and a mobile station during the re-authentication phase. Furthermore, the proposed scheme gives little burden over the proactive key pre-distribution scheme while satisfying 802.11i security requirements.