There are so many Linux bandwidth monitoring software available out there. Many of these software are just showing the current upload and download speed of each network interface, pretty much similar to iptraf‘s “General interface statistics”. I was looking for something that plots TUI graphs. I found nload after spending a few minutes on Google. It doesn’t produce pretty graphs like rrdtool, but at least it does what I need.
UPDATE: I just noticed that ifstatus is similar to nload. ifstatus is capable of producing colored TUI graphs.