One time password (OTP) technology enables a plurality of OTP software token instances (or copies) to be used simultaneously on a plurality of computing devices of a user. OTP software instances may be counter based. An authentication server comprising authentication software assigns a set of counters for each OTP software instance. An OTP software instance may be provided along with the assigned set of counters to each computing device. A range of counters may be partitioned by the authentication server into mutually exclusive sets of counters. An OTP software instance executed by a computing device uses one of the counters in the assigned set of counters to provide an OTP. The authentication server attempts authentication by using each counter in the assigned set of counters to provide a calculated OTP that is compared to the received OTP. The authentication server verifies authenticity when a calculated OTP matches a received OTP.
