The JNFS server runs as a user-level daemon as the privileged user (for example, root on UNIX, or any user with the Administrative Privilege on Windows NT). It serves out files from the underlying file system(s) used by the host operating system. Thus, if the server's operating system provides support for distributed file systems such as NFS, JNFS will serve those files out as well.
JNFS also employs a small number of native method calls to obtain file permission information from the underlying file system. The authorization policy is discussed in detail in Section 4.2.