What is the function of the iftop command?

The iftop command is primarily used to monitor network bandwidth in real time. It provides a visual representation of network traffic, displaying which hosts are sending and receiving the most data. This tool captures packets and presents the information in a meaningful way, allowing users to see the bandwidth usage of different connections. It highlights the source and destination of traffic, as well as the amount of data being transferred over a specified period.

While there are other tools and commands that can analyze packet loss, perform ICMP testing (like ping), or trace routing paths (like traceroute), iftop specifically focuses on network bandwidth usage, making it invaluable for network administrators looking to understand traffic patterns, diagnose bandwidth issues, or monitor ongoing network activity. This specialization in bandwidth monitoring is what distinguishes iftop from the other options listed.