IPTraf-ng is a console-based network monitoring program for Linux that
displays information about IP traffic. It returns such information as:
Current TCP connections
UDP, ICMP, OSPF, and other types of IP packets
Packet and byte counts on TCP connections
IP, TCP, UDP, ICMP, non-IP, and other packet and byte counts
TCP/UDP counts by ports
Packet counts by packet sizes
Packet and byte counts by IP address
Interface activity
Flag statuses on TCP packets
LAN station statistics