This value is the password used to authenticate the gateway's registration with the Gatekeeper, where its length signals its form: zero length clears the password and disables gatekeeper security, 1 to 16 characters is a plaintext password, and 24 characters is an encrypted password string. An administrator writes an empty value to quickly disable gatekeeper security-call authentication, or a plaintext string to set a new password. For example, writing a 16-character string like "MyGkSecret123456" sets a cleartext registration password, while writing an empty string clears it and disables the security capacity.