Graphical system- and process-monitoring tools that come with Ubuntu include the following:
vncviewer—AT&T’s open-source remote session manager (part of the Xvnc package), which you can use to view and run a remote desktop session locally. This software (discussed in more detail in Chapter 17, “Remote Access with SSH and Telnet”) requires an active, background, X session on the remote computer.
gnome-nettool—A GNOME-developed tool that enables system administrators to carry out a wide range of diagnostics on network interfaces, including port scanning and route tracing.
ethereal—A graphical network protocol analyzer that can be used to save or display packet data in real time and has intelligent filtering to recognize data signatures ...