Internet Protocol Version 4

Internet Protocol version 4 (IPv4)is the fourth iteration of the Internet Protocol (IP) and it is the first version of the protocol to be widely deployed. IPv4 is the dominant internet layer protocol on the Internet and apart from IPv6 it is the only standard network-layer protocol used on the Internet.

IPv4 is a data-oriented protocol to be used on a packet-switched network (e.g., Ethernet). It is a best effort protocol in that it does not guarantee delivery. It does not make any guarantees on the correctness of the data; this may result in duplicated packets or packets delivered out of order. These aspects are addressed by an upper layer protocol (e.g. TCP, and partly by UDP).