public int getAuthenticationTimeout() throws GuacamoleException {
        return environment.getProperty(DUO_AUTH_TIMEOUT, 5);
    }
Returns the maximum amount of time to allow for an in-progress Duo
authentication attempt to be completed, in minutes. A user that takes
longer than this amount of time to complete authentication with Duo
will need to try again.

@return
    The maximum amount of time to allow for an in-progress Duo
    authentication attempt to be completed, in minutes.

@throws GuacamoleException
    If the authentication timeout cannot be parsed.
extensions/guacamole-auth-duo/src/main/java/org/apache/guacamole/auth/duo/conf/ConfigurationService.java