The present invention relates to a method for protecting the security of a computer network which is accessed through the use of wireless devices, among other means. Specifically, the present invention pertains to a method of using user-specific biometric data to identify users of wireless devices such as PDAs and yet prevent use by unauthorized persons and prevent changing of the biometric data by unauthorized persons. The method also prevents unauthorized access, and facilitates authorized access, to computer networks. Control of access to the biometric data and control of access to the network can be maintained in the network administrator or other responsible body and thereby also offers security against theft.