Internet Protocol
<networking> (IP) The network layer for the TCP/IP protocol suite widely used on Ethernet networks, defined in STD 5, RFC 791.
IP is a connectionless, best-effort {packet switching} protocol.
It provides packet routing, fragmentation and re-assembly through the data link layer.
IPv4 is the version in widespread use and IPv6 is just beginning to come into use in 2000.
[Other versions? Dates?]