Several protocols have been proposed to provide robust mutual authentication and key establishment for wireless local area network (WLAN). In this paper we present a New Authenticated Key Agreement (NAKA) protocol that provides secure mutual authentication, key establishment and key confirmation over an untrusted network. The main comparative study of our proposed protocol concerns the performance capabilities, including computational and communication load. In addition, the new protocol achieves many of the required security properties. It can resist dictionary attacks mounted by either passive or active networks intruders, allowing even the use of a weak password to be used. It can resist Impersonate attack. It also offers perfect forward secrecy which protects past sessions and passwords against future compromise. Finally, it can resist known-key and resilience to server attack. Our proposed protocol combines techniques of challenge-response protocols with symmetric key agreement protocols and offers significantly improved performance in computational and communication load over comparably many authenticated key agreement protocols such as B-SPEKE, SRP, AMP, PAK-RY, PAK-X, SKA and LR-AKE.