Password authentication device, recording medium, and password authentication method

A non-transitory computer-readable recording medium that stores a password authentication program, the password authentication program causing a computer to execute a password authentication process, wherein the password authentication process comprises:

• storing a reference value of period information for each user;
• acquiring the period information when the user inputs a password;
• authenticating the user when a difference between the reference value of the period information and the period information acquired when the password is input is equal to or less than a specified value;
• and updating the reference value of the period information based on the period information acquired when the password is input, the period information includes a password input period, a depression period proportion, and a period-between-characters proportion, the password input period indicates a period from when the user starts inputting the password until the user completes the input, the depression period proportion indicates a proportion that a depression period occupies the password input period, the depression period indicates a period from a time point of starting inputting each character constituting the password until a time point of completing the input, the period-between-characters proportion indicates a proportion that a period-between-characters occupies the password input period, and the period-between-characters indicates a period from a time point of completing inputting a specific character constituting the password until a time point of starting inputting a character subsequent to the specific character.

A password authentication method comprising:

• storing a reference value of period information for each user;
• acquiring the period information when the user inputs a password;
• authenticating the user when a difference between the reference value of the period information and the period information acquired when the password is input is equal to or less than a specified value;
• and updating the reference value of the period information based on the period information acquired when the password is input, wherein the period information includes a password input period, a depression period proportion, and a period-between-characters proportion, the password input period indicates a period from when the user starts inputting the password until the user completes the input, the depression period proportion indicates a proportion that a depression period occupies the password input period, the depression period indicates a period from a time point of starting inputting each character constituting the password until a time point of completing the input, the period-between-characters proportion indicates a proportion that a period-between-characters occupies the password input period, and the period-between-characters indicates a period from a time point of completing inputting a specific character constituting the password until a time point of starting inputting a character subsequent to the specific character.