NFS security

Is there any doc or wisdom that explains better how to secure directories between two IBM I systems with an NFS export/mount. What we'd like to do is on the main system, export directory called /foo, then mount /foo on the client system. We would like to be able to secure directories under /foo such as /foo/abc to only users authorized to /foo/abc and others /foo/xyz only users authorized to /foo/xyz. In reading about nfs mounts, it says that UID is used, but is that only when the host is a *NIX system? Can I match userid on system A with a userid on system B if they have the same UID?

Dana

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