Improper configuration of X Windows can allow the compromise of your password and the exposure of your display. Please secure your system's X services!
A primary precaution is that the command "xhost +" should NOT be used. It gives any computer access to your display and keyboard.An good presentation of how X11 works and how to secure it is presented in this CIAC document.
The X11 package provided by Apple may, depending on your original installation process, already be installed. Open Finder and search for X11. If the package is not installed, point a browser window to www.apple.com and search Downloads for X11 Extension. (I found the software here, http://www.apple.com/downloads/macosx/unix_open_source/x11extension.html but please remember that Apple updates their web pages often.)
Download the package, then install. It should install into the utilities folder of your primary hard drive.
After X11 is installed, reboot the computer. After rebooting, you should see a new icon in your dock with a large X in the middle of it.
Open a terminal window by double-clickin on the X icon, then at the prompt type
ssh -X hostname
(where hostname refers to a unix server, e.g., jlabs1, jlabs2, farml1)
After you've connected to the server of choice, type the appropriate command to start the GUI software of your choice.
This document is maintained by {helpdesk@jlab.org}
Copyright Jefferson Lab 2007