The Java Tutorials have been written for JDK 8. Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.
See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.
As just stated, the default authentication mechanism is "none" if no authentication environment properties have been set. If the client sets the Context.SECURITY_AUTHENTICATION environment property to "none", then the authentication mechanism is "none" and all other authentication environment properties are ignored. You would want to do this explicitly only to ensure that any other authentication properties that might have been set are ignored. In either case, the client will be treated as an anonymous client. This means that the server does not know or care who the client is and will allow the client to access (read and update) any data that has been configured to be accessible by any unauthenticated client.
Because none of the directory examples in the Naming and Directory Operations lesson set any of the authentication environment properties, all of them use anonymous authentication.
Here is
an example
that explicitly sets the Context.SECURITY_AUTHENTICATION property to "none" (even though doing this is not strictly necessary because that is the default).
// Set up the environment for creating the initial context Hashtable<String, Object> env = new Hashtable<String, Object>(); env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory"); env.put(Context.PROVIDER_URL, "ldap://localhost:389/o=JNDITutorial"); // Use anonymous authentication env.put(Context.SECURITY_AUTHENTICATION, "none"); // Create the initial context DirContext ctx = new InitialDirContext(env); // ... do something useful with ctx