Internet Protocol This article is about the IP network protocol only. For Internet architecture or other protocols, see Internet protocol suite. The Internet Protocol (IP) is the principal communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. Historically, IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974; the other being the connection-oriented Transmission Control Protocol (TCP). The Internet protocol suite is therefore often referred to as TCP/IP. The first major version of IP, Internet Protocol Version 4 (IPv4), is the dominant protocol of the Internet. Function[edit] The Internet Protocol is responsible for addressing hosts and for routing datagrams (packets) from a source host to a destination host across one or more IP networks. Datagram construction[edit] Reliability[edit]
Introduction to the Internet Protocol, Course 201 Actually TCP/IP is a set of protocols defined by a series of RFCs (request for comments) that have evolved over the years. In general the Internet Protocol (IP) is used to route messages between networks and, therefore, properly resides at the network layer of the OSI Reference Model. Transmission Control Protocol (TCP) sits on top of IP and is used to guarantee the delivery of messages. Above TCP is the application layer. The services of the presentation and session layers of the OSI Reference Model are incorporated into the application layer. The data sent over wires is represented as frames. This wrapping of data within the data field of the next immediate lower layer of the protocol stack is called encapsulation while the unwrapping of the same data at the receiving side is called demultiplexing. (No part of this article may be reproduced without the written consent of the Industrial Ethernet University.)
Daily | Mises Institute Libertarians often cite the internet as a case in point that liberty is the mother of innovation. Opponents quickly counter that the internet was a government program, proving once again that markets must be guided by the steady hand of the state. In one sense the critics are correct, though not in ways they understand. The internet indeed began as a typical government program, the ARPANET, designed to share mainframe computing power and to establish a secure military communications network. Of course the designers could not have foreseen what the (commercial) internet has become. In fact, the role of the government in the creation of the internet is often understated. The internet owes its very existence to the state and to state funding. During the 1960s, the RAND Corporation had begun to think about how to design a military communications network that would be invulnerable to a nuclear attack. By 1972, the number of host computers connected to the ARPANET had increased to 37.
IP Datagram Encapsulation IP Datagram Encapsulation In the chapter describing the OSI Reference Model, I looked at several ways that protocols at various layers in a networking protocol stack interact with each other. One of the most important concepts in inter-protocol operation is that of encapsulation. A good analogy for how encapsulation works is a comparison to sending a letter enclosed in an envelope. Due to the prominence of TCP/IP, the Internet Protocol is one of the most important places where data encapsulation occurs on a modern network. If the message to be transmitted is too large for the size of the underlying network, it may first be fragmented. The IP datagram is somewhat similar in concept to a frame used in Ethernet or another data link layer. After data is encapsulated into an IP datagram, it is passed down to the data link layer for transmission across the current “hop” of the internetwork. Home - Table Of Contents - Contact Us
Did Al Gore Claim He Invented the Internet? Claim: Vice-President Al Gore claimed during a news interview that he "invented" the Internet. Origins: Despite the derisive references that continue even today, former Vice-President Al Gore never claimed that he "invented" the Internet, nor did he say anything that could reasonably be interpreted that way. The "Al Gore said he 'invented' the Internet" put-downs were misleading, out-of-context distortions of something he said during an interview with Wolf Blitzer on CNN's "Late Edition" program on 1999. When asked to describe what distinguished him from his challenger for the Democratic presidential nomination, Senator Bill Bradley of New Jersey, Gore replied (in part): During my service in the United States Congress, I took the initiative in creating the Internet. Al Gore was the first political leader to recognize the importance of the Internet and to promote and support its development. No one person or even small group of persons exclusively "invented" the Internet.
Linux IP Networking: A Guide to the Implementation and Modification of the Linux Protocol Stack Glenn Herrin Department of Computer ScienceUniversity of New Hampshire May 31, 2000 Abstract This document is a guide to understanding how the Linux kernel (version 2.2.14 specifically) implements networking protocols, focused primarily on the Internet Protocol (IP). It is intended as a complete reference for experimenters with overviews, walk-throughs, source code explanations, and examples. 1.1 Background Linux is becoming more and more popular as an alternative operating system. This document is an effort to bring together many of these sources into one coherent reference on and guide to modifying the networking code within the Linux kernel. As a reference for kernel programmers, this document includes information and pointers on editing and recompiling the kernel, writing and installing modules, and working with the /proc file system. 1.2 Document Conventions It is assumed that the reader understands the C programming language and is acquainted with common network protocols.
How Government Did (and Didn't) Invent the Internet Last night, I happened across an article by Slate technology scribe Farhad Manjoo. He was responding to an opinion piece in the Wall Street Journal by the Journal’s former publisher Gordon Crovitz. And when Manjoo explained just what Crovitz was opining about, I felt my jaw drop to the floor as if I were a character in a 1940s cartoon. Crovitz, apparently riled up over Barack Obama’s “you didn’t build that” kerfuffle, has an example of something that the government is widely misperceived to have built: the Internet. He actually says, “It’s an urban legend that the government launched the Internet.” As Manjoo points out, Crovitz’s argument — which rests largely on his contention that the Internet was really created at Xerox’s legendary PARC lab — is bizarrely, definitively false. Also factual: DARPA was where Robert Kahn and Vint Cerf invented TCP/IP, the plumbing that makes the Internet possible. (Crovitz, incidentally, credits Berners-Lee for the hyperlink.
tcpip - What's the difference between a TCP segment and a TCP packet? Microsoft Grabs No-IP Websites [Chapter 6] 6.3 What Does a Packet Look Like? To understand packet filtering, you first have to understand packets and how they are handled at each layer of the TCP/IP protocol stack: Packets are constructed in such a way that layers for each protocol used for a particular connection are wrapped around the packets, like the layers of skin on an onion. At each layer, a packet has two parts: the header and the body. The header contains protocol information relevant to that layer, while the body contains the data for that layer which often consists of a whole packet from the next layer in the stack. At the application layer, the packet consists simply of the data to be transferred (for example, part of a file being transferred during an FTP session). At the other side of the connection, this process is reversed. In trying to understand packet filtering, the most important information from our point of view is in the headers of the various layers. 6.3.1 TCP/IP /Ethernet Example 6.3.1.1 Ethernet layer 6.3.1.2 IP layer 6.3.1.3 TCP layer