a) One of the computer networking protocols that are antecedents or descendants of that specified by the IETF STD005, "INTERNET PROTOCOL"; all of which are characterized by providing routable internetwork addressing and by being packet-switched, unreliable, and connectionless.
b) The most widely used of these protocols, IPv4.
See Also: dotted quad, ICMP, IPv4, IPv6, IP address, TCP, TCP/IP, UDP
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