1. Field of the Invention
The present invention relates to an authentication processing device which performs authentication processing according to inputted authentication information.
2. Description of the Related Art
In general, in an information processing device such as a PC (personal computer), a tablet terminal device, or a portable terminal device, when authentication processing such as identity verification is performed, a passphrase with a large number of characters is used, among passwords (authentication information) for use in authentication, whereby high-level security can be achieved and a significant reduction of the danger of violating authentication can be expected. However, the large number of characters disadvantageously makes it difficult for a user to remember the passphrase.
To overcome this disadvantage, a technology has been conventionally provided in which, even if a four-digit password is used, security can be enhanced by setting the input positions and the input sequence of characters in the password in advance (refer to Japanese Patent Application Laid-Open (Kokai) Publication No. 2000-339084).
In the above-described technology, in the case of a password with a large number of digits such as a passphrase, a user has to memorize the input positions and the input sequence of the digits and input the password by recalling the input position and the input sequence for each digit. This puts a great burden on the user. Conversely, when the number of digits of the password is small, if a third party steals a glance at or secretly photographs the password with the last digit inputted, there is a danger that authentication is violated after repeating input errors several times.