(Ntop displays network usage in a process-manager-like way. In the program mode, it can display the network status on the user terminal. In page mode, it acts as a page server and displays network conditions in HTML document mode. It is a NetFlow/sFlow transmitter and collector. It generates an ntop-centric monitoring program through an HTTP-based client interface. RRD (RoundRobinDatabase) (Ring Database) is used to continuously store network communication status information.)