Internet Protocol

IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974, which was complemented by a connection-oriented service that became the basis for the Transmission Control Protocol (TCP).

[2] For these purposes, the Internet Protocol defines the format of packets and provides an addressing system.

IP routing is performed by all hosts, as well as routers, whose main function is to transport packets across network boundaries.

[5] The paper's authors, Vint Cerf and Bob Kahn, described an internetworking protocol for sharing resources using packet switching among network nodes.

The design of the Internet protocol suite adheres to the end-to-end principle, a concept adapted from the CYCLADES project.

No central monitoring or performance measurement facility exists that tracks or maintains the state of the network.

As a consequence of this design, the Internet Protocol only provides best-effort delivery and its service is characterized as unreliable.

In network architectural parlance, it is a connectionless protocol, in contrast to connection-oriented communication.

IPv6, by contrast, operates without header checksums, since current link layer technology is assumed to provide sufficient error detection.

[16][17] The dynamic nature of the Internet and the diversity of its components provide no guarantee that any particular path is actually capable of, or suitable for, performing the data transmission requested.

[18] The IPv4 internetworking layer automatically fragments a datagram into smaller units for transmission when the link MTU is exceeded.

[21] During the design phase of the ARPANET and the early Internet, the security aspects and needs of a public, international network could not be adequately anticipated.

Consequently, many Internet protocols exhibited vulnerabilities highlighted by network attacks and later security assessments.