This thesis presents a design and implementation for new wireless LAN authentication protocol by apply the unique key for each mobile user instead of the shared key that s used for the all users. The benefits of the one key for each user added to one key for each operation make the RSA algorithm is more efficient and active to be applied in any authentication protocol. This thesis apply the design of using RSA algorithm as encryption algorithm in WEP authentication protocol, that applied for peer to peer topology to establish an authentic data communication link between any two or more wireless clients. That will give the wireless client user ability of having a secret key that used to prove his identity. The WEP supporting by RSA algorithm authentication protocol increase the security level of the data transmission in WLAN because of the mathematical operation that used in RSA key generation is deepened on estimation and probability of choosing the values of parameters, so it will be more difficulty to be attack .