tcpdump: tcpdump (network monitor) tcpdump: tcpdump: Tcpdump is a tool for network monitoring and data acquisition. You tcpdump: can use it to dump information on all the packets on a network that tcpdump: match a boolean expression. Tcpdump uses libpcap, a system tcpdump: independent interface for user-level packet capture. tcpdump: tcpdump: tcpdump: tcpdump: tcpdump: