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Transmission Control Protocol

Transmission Control Protocol
Web browsers use TCP when they connect to servers on the World Wide Web, and it is used to deliver email and transfer files from one location to another. HTTP, HTTPS, SMTP, POP3, IMAP, SSH, FTP, Telnet and a variety of other protocols are typically encapsulated in TCP. Historical origin[edit] In May 1974 the Institute of Electrical and Electronic Engineers (IEEE) published a paper titled "A Protocol for Packet Network Intercommunication Network function[edit] The protocol corresponds to the transport layer of TCP/IP suite. TCP is utilized extensively by many of the Internet's most popular applications, including the World Wide Web (WWW), E-mail, File Transfer Protocol, Secure Shell, peer-to-peer file sharing, and some streaming media applications. TCP is optimized for accurate delivery rather than timely delivery, and therefore, TCP sometimes incurs relatively long delays (on the order of seconds) while waiting for out-of-order messages or retransmissions of lost messages. Reserved (3 bits) Related:  Infrastructure internet

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]

RFC 675 - Specification of Internet Transmission Control Program [Docs] [txt|pdf] Network Working Group Vinton Cerf Request for Comments: 675 Yogen Dalal NIC: 2 Carl Sunshine INWG: 72 December 1974 December 1974 Version This document describes the functions to be performed by the internetwork Transmission Control Program [TCP] and its interface to programs or users that require its services. RFC 675 Specification of Internet TCP December 1974 A pair of sockets form a CONNECTION which can be used to carry data in either direction [i.e. full duplex]. RFC 675 Specification of Internet TCP December 1974 At a GATEWAY between networks, the internetwork packet is unwrapped from its local packet format and examined to determine through which network the internetwork packet should travel next. 2. 2.1 The TCP as a POST OFFICE The TCP acts in many ways like a postal service since it provides a way for processes to exchange letters with each other. RFC 675 Specification of Internet TCP December 1974 2.2 Sockets and Addressing 2.3.1 A Note on Style

Hypertext Transfer Protocol The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems.[1] HTTP is the foundation of data communication for the World Wide Web. The standards development of HTTP was coordinated by the Internet Engineering Task Force (IETF) and the World Wide Web Consortium (W3C), culminating in the publication of a series of Requests for Comments (RFCs), most notably RFC 2616 (June 1999), which defined HTTP/1.1, the version of HTTP most commonly used today. In June 2014, RFC 2616 was retired and HTTP/1.1 was redefined by RFCs 7230, 7231, 7232, 7233, 7234, and 7235.[2] HTTP/2 is currently in draft form. Technical overview[edit] URL beginning with the HTTP scheme and the WWW domain name label. A web browser is an example of a user agent (UA). HTTP is designed to permit intermediate network elements to improve or enable communications between clients and servers. History[edit] The first documented version of HTTP was HTTP V0.9 (1991).

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.

RFC 793 - Transmission Control Protocol [Docs] [txt|pdf] [Errata] Updated by: 1122, 3168, 6093, 6528 INTERNET STANDARD Errata Exist RFC: 793 TRANSMISSION CONTROL PROTOCOL DARPA INTERNET PROGRAM PROTOCOL SPECIFICATION September 1981 prepared for Defense Advanced Research Projects Agency Information Processing Techniques Office 1400 Wilson Boulevard Arlington, Virginia 22209 by Information Sciences Institute University of Southern California 4676 Admiralty Way Marina del Rey, California 90291 September 1981 Transmission Control Protocol TABLE OF CONTENTS PREFACE ........................................................ iii 1. September 1981 Transmission Control Protocol [Page ii] September 1981 Transmission Control Protocol PREFACE This document describes the DoD Standard Transmission Control Protocol (TCP). RFC: 793 Replaces: RFC 761 IENs: 129, 124, 112, 81, 55, 44, 40, 27, 21, 5 TRANSMISSION CONTROL PROTOCOL DARPA INTERNET PROGRAM PROTOCOL SPECIFICATION 1. 1.1. 1.2. 1.3. 1.4. 1.5. 2.1. 2.2.

Application layer Although both models use the same term for their respective highest level layer, the detailed definitions and purposes are different. In the OSI model, the definition of the application layer is narrower in scope. The OSI model defines the application layer as the user interface responsible for displaying received information to the user. In contrast, the Internet Protocol model does not concern itself with such detail. TCP/IP protocols[edit] The IETF definition document for the application layer in the Internet Protocol Suite is RFC 1123. Remote login to hosts: TelnetFile transfer: File Transfer Protocol (FTP), Trivial File Transfer Protocol (TFTP)Electronic mail transport: Simple Mail Transfer Protocol (SMTP)Networking support: Domain Name System (DNS)Host initialization: BOOTPRemote host management: Simple Network Management Protocol (SNMP), Common Management Information Protocol over TCP (CMOT) Other protocol examples[edit] References[edit] External links[edit]

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.

RFC 2581 - TCP Congestion Control [Docs] [txt|pdf] [draft-ietf-tcpimp...] [Diff1] [Diff2] [Errata] Obsoleted by: 5681 PROPOSED STANDARDUpdated by: 3390 Errata Exist Network Working Group M. 1. This document specifies four TCP [Pos81] congestion control algorithms: slow start, congestion avoidance, fast retransmit and fast recovery. RFC 2581 TCP Congestion Control April 1999 This document is organized as follows. 2. This section provides the definition of several terms that will be used throughout the remainder of this document. RFC 2581 TCP Congestion Control April 1999 LOSS WINDOW (LW): The loss window is the size of the congestion window after a TCP sender detects loss using its retransmission timer. 3. This section defines the four congestion control algorithms: slow start, congestion avoidance, fast retransmit and fast recovery, developed in [Jac88] and [Jac90]. 3.1 Slow Start and Congestion Avoidance RFC 2581 TCP Congestion Control April 1999 3.2 Fast Retransmit/Fast Recovery 4. 4.1 Re-starting Idle Connections

Transport layer Transport layer implementations are contained in both the TCP/IP model (RFC 1122),[2] which is the foundation of the Internet, and the Open Systems Interconnection (OSI) model of general networking, however, the definitions of details of the transport layer are different in these models. In the Open Systems Interconnection model the transport layer is most often referred to as Layer 4. The best-known transport protocol is the Transmission Control Protocol (TCP). It lent its name to the title of the entire Internet Protocol Suite, TCP/IP. Services[edit] Transport layer services are conveyed to an application via a programming interface to the transport layer protocols. Analysis[edit] The transport layer is responsible for delivering data to the appropriate application process on the host computers. Some transport layer protocols, for example TCP, but not UDP, support virtual circuits, i.e. provide connection oriented communication over an underlying packet oriented datagram network.

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.

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