A novel protocol to achieve privacy-preserving universal authentication protocol for wireless communications called Priauth. to secure the communication as the data are sensitive or it requires the users to pay for it. In the algorithms for secure communication a key is shared by H with V and V with users. The key is used to encrypt data transmitted to the servers or users. In privacy based authentication protocols besides the user and its home server, no one including the foreign server can tell the identity of the user; and besides the user and its home server, no one including the foreign server is able to link any past or future protocol runs of the same user. An To revoke multiple users is to associate a key with every nonempty subset of users in the group. Thus, if one or more users are revoked, the VA uses the key associated with the subset of the remaining users to encrypt the new key and transmits the new group key to them. The advantage of this approach is that the communication overhead is only one message for revoking any number of users. However, the number of keys stored by the VA and the users is exponential in the size of the group. The goal of the enhancement is to evaluate trade-off between storage and revocation cost. Storage is computed in terms of keys that each user (respectively, VA) maintains. And revocation cost is computed in terms of the encryptions performed, and the number of messages transmitted, by the VA.