When one enters a password to access one's online account, one has to type out the complete password, and submit it to be authenticated. If the password is very long, and if the account is accessed regularly, it will be very tiring to type out the full password over and over again.
Are there any schemes where the user types in a long password, and at every keystroke, the server checks whether or not the password provided so far is satisfactory? If it is satisfactory, the system logs the user in before the user finishes typing the password.
Do such schemes exist?