Port
1. <networking> A logical channel or channel endpoint in a communications system.
The
Transmission Control Protocol and
User Datagram Protocol transport layer protocols used on
Ethernet use port numbers to distinguish between (demultiplex) different logical channels on the same network interface on the same computer.
Each
application program has a unique port number associated with it, defined in /etc/services or the
Network Information Service "services" database.
Some protocols, e.g.
telnet and
HTTP (which is actually a special form of telnet) have default ports specified as above but can use other ports as well.
Some port numbers are defined in
RFC 1700, divided into well-known ports and registered ports.
2. <operating system, programming> To translate or modify
software to run on a different
platform, or the results of doing so.
The
portability of the software determines how easy it is to port.
3. <language> An imperative language descended from
Zed from Waterloo Microsystems (now
Hayes Canada) ca. 1979.
["Port Language" document in the Waterloo Port Development System].
