NFS
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A work in progress.
The Network File System, or NFS, is one of the things that should have been pulling the UNIX-like operating environments ahead for some time. Sadly, it's a tricky beast to tame, and its implementation isn't always so rock-solid.
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Comparing to Windows
Of course, we're not trying to position Windows as the environment to follow. We use it here only as the system that works differently than the others, and one with which most readers are familiar (market share has benefits). Solaris, BSD, LINUX, Mac, AIX, and the real UNIX and others all have NFS support. For the most part they interact well, too.
In fact, Windows is lacking in this area, and has to rely on Samba to connect to those other environments without additional software on the Windows systems. This is not discussed here, as the focus of this documentation is to get two NFS-friendly systems behaving together (one server, one client). Once we get through that, adding more clients or servers should be trivial.
Only Root Allowed
One major obstacle is that only root can mount resources on most systems. In small groups this might not be a problem, as users can be trusted with root access.
Contrary to this, Microsoft Windows allows users to connect to shares as long as that user has permission on the remote system.
Similarly, only root can share directories to be mounted. This can be worked around by allowing mounting of subdirectories, but some security is risked.
Again, Windows allows almost anyone to set up a share, and then there are permissions per-share and within the directory structure shared.
How to get around this?
The easiest solution is to have root mount the directory, but specify it as user mounted. When the user accesses the share their permissions will be compared to those of the user with the same ID on the server. What?
Automounting By User Is Difficult
Similar to only allowing root to mount is the issue of per-user mounting. Using centralized authentication helps. To be fair, this is often required on Windows systems.
References
Linux Documentation Project's NFS How-to (http://www.tldp.org/HOWTO/NFS-HOWTO)
Troubleshooter.com's NFS Overview and Gotchas (http://www.troubleshooters.com/linux/nfs.htm)