The service password-encryption command is used to encrypt passwords on Cisco routers. It is used to encrypt all passwords configured on the router, both current and future. This means all passwords in the plain text configuration file will be encrypted. This command is issued in global configuration mode. The syntax of the command is as follows:
Router(config)# service password-encryption
This command does not have any parameters.

Once executed any password in the configuration file will appear similar to what is shown below when the running or startup configuration files are viewed:
R1#show run <Output omitted> ! line console 0 password 7 09-4f60C0B1C1B login <Output omitted>
The password secure and service encryption-password commands are incorrect because they are not valid Cisco IOS commands.

The enable password command is used to set the privileged EXEC mode password, and does not encrypt the password by default.