Glossary: TCP/IP in Depth, Part 1
port
Also written: port 53, port 80
A number that names a service on a machine, such as 53 for DNS or 80 for the web server. tcpdump writes it after the last dot of an address, as in 192.168.10.1.53.
Where the book teaches it
Related terms
UDP (User Datagram Protocol)TCP (Transmission Control Protocol)port unreachable