Abstract: A method and/or system for validating subscribers includes an insecure communications network, such as, an IS-41 wireless telephone network connecting a plurality of telephone switches. A subscriber or user of the system enters a sequence of digits, namely, a random PIN (personal identification number), and a telephone number of whom he wishes to call. The random PIN provides effectively a “digital signature” to the telephone number. A second number is dialed to effect call completion. An authentication center exists which authenticates the user by verifying the digital signature and updating a user profile to permit a call only to the telephone number in the sequence dialed by the user. The profile is sent to the serving switch which permits calls only to the destination in the profile. This technique eliminates fraudulent users from stealing telephone identities, “cloning” phones and placing calls. Calls are optionally completed only to destinations that have been validated.