I am using RHEL 7 with GNOME 3. As far as I know, I can only configure an ADSL connection (via GUI) with nm-connection-editor. But where can I find a clickable symbol for the nm-connection-editor in the GUI? It should be available, but when digging around in network manager (with the mouse) it doesn't bring up nm-connection-editor!Or is the only solution for configuring ADSL to press ALT+F2, then type nm-connection-editor? How user friendly is that? 
How to reach nm-connection-editor from the GUI in GNOME 3?
gnome3;networkmanager
The documentation of the Network Manger project points out that it's the dekstop environment authors' responsibility to integrate nm-connection-editor with their GUIs:Most desktops provide a control center or settings utility that integrates with NetworkManager. You can also use 'nm-connection-editor', 'nmcli' or 'nmtui' tools directly.This does not seem to have been done in RHEL and its derivatives (nor in most other distributions), and answers like this one on Superuser and the NetworkManager documentation from ArchLinux (who generally ship their packages as they are upstream, without alterations) suggest that it has been like that since Gnome 3 came out. Let's check to make sure:$ locate nm-connection-editor.desktop/usr/share/applications/nm-connection-editor.desktopOK, so there is a launcher for that program deployed with the system, but...$ tail -n 2 /usr/share/applications/nm-connection-editor.desktopCategories=GNOME;GTK;Settings;X-GNOME-NetworkSettings;NotShowIn=KDE;GNOME;...the last line of that .desktop file clearly shows that someone on the DE or distribution level decided to not show that symbol in KDE and GNOME.In summary, yes, you will need to launch the program directly, either via the Alt-F2 prompt or via a terminal. Creating a launcher yourself will, of course, also work.