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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Network socket</span></span>

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<p>A <b>network socket</b> is a software structure within a <a href="Network_node" class="mw-redirect" title="Network node">network node</a> of a <a href="Computer_network" title="Computer network">computer network</a> that serves as an endpoint for sending and receiving data across the network. The structure and properties of a socket are defined by an <a href="Application_programming_interface" class="mw-redirect" title="Application programming interface">application programming interface</a> (API) for the networking architecture. Sockets are created only during the lifetime of a <a href="Process_(computing)" title="Process (computing)">process</a> of an application running in the node.

</p><p>Because of the <a href="Standardization" title="Standardization">standardization</a> of the <a href="TCP/IP" class="mw-redirect" title="TCP/IP">TCP/IP</a> protocols in the development of the <a href="Internet" title="Internet">Internet</a>, the term <i>network socket</i> is most commonly used in the context of the Internet protocol suite, and is therefore often also referred to as <b>Internet socket</b>. In this context, a socket is externally identified to other hosts by its <b>socket address</b>, which is the triad of <a href="Transport_protocol" class="mw-redirect" title="Transport protocol">transport protocol</a>, <a href="IP_address" title="IP address">IP address</a>, and <a href="Port_number" class="mw-redirect" title="Port number">port number</a>.

</p><p>The term <i>socket</i> is also used for the software endpoint of node-internal <a href="Inter-process_communication" title="Inter-process communication">inter-process communication</a> (IPC), which often uses the same API as a network socket.

</p>

<p>The use of the term <i>socket</i> in software is analogous to the function of an electrical <a href="Female_connector" class="mw-redirect" title="Female connector">female connector</a>, a device in hardware for communication between nodes interconnected with an <a href="Electrical_cable" title="Electrical cable">electrical cable</a>. Similarly, the term <i><a href="Port_(computer_networking)" title="Port (computer networking)">port</a></i> is used for external physical endpoints at a node or device.

</p><p>The application programming interface (API) for the network protocol stack creates a <a href="Handle_(computing)" title="Handle (computing)">handle</a> for each socket created by an application, commonly referred to as a <i>socket descriptor</i>. In <a href="Unix-like_operating_system" class="mw-redirect" title="Unix-like operating system">Unix-like operating systems</a>, this descriptor is a type of <a href="File_descriptor" title="File descriptor">file descriptor</a>. It is stored by the application process for use with every read and write operation on the communication channel.

</p><p>At the time of creation with the API, a network socket is bound to the combination of a type of network protocol to be used for transmissions, a network address of the host, and a <a href="Port_number" class="mw-redirect" title="Port number">port number</a>. Ports are numbered resources that represent another type of software structure of the node. They are used as service types, and, once created by a process, serve as an externally (from the network) addressable location component, so that other hosts may establish connections.

</p><p>Network sockets may be dedicated for persistent connections for communication between two nodes, or they may participate in <a href="Connectionless" class="mw-redirect" title="Connectionless">connectionless</a> and <a href="Multicast" title="Multicast">multicast</a> communications.

</p><p>In practice, due to the proliferation of the TCP/IP protocols in use on the Internet, the term <i>network socket</i> usually refers to use with the <a href="Internet_Protocol" title="Internet Protocol">Internet Protocol</a> (IP). It is therefore often also called <b>Internet socket</b>.

</p>

<div class="mw-heading mw-heading2"><h2 id="Socket_addresses">Socket addresses</h2></div>

<p>An application can communicate with a remote process by exchanging data with TCP/IP by knowing the combination of protocol type, IP address, and port number. This combination is often known as a <i>socket address</i>. It is the network-facing access handle to the network socket. The remote process establishes a network socket in its own instance of the protocol stack and uses the networking API to connect to the application, presenting its own socket address for use by the application.

</p>

<div class="mw-heading mw-heading2"><h2 id="Implementation">Implementation</h2></div>

<p>A <a href="Protocol_stack" title="Protocol stack">protocol stack</a>, usually provided by the <a href="Operating_system" title="Operating system">operating system</a> (rather than as a separate library, for instance), is a set of services that allows processes to communicate over a network using the protocols that the stack implements. The operating system forwards the payload of incoming IP packets to the corresponding application by extracting the socket address information from the IP and transport protocol headers and stripping the headers from the application data.

</p><p>The application programming interface (API) that programs use to communicate with the protocol stack, using network sockets, is called a <b>socket API</b>. Development of application programs that utilize this API is called <i>socket programming</i> or <i><a href="Computer_network_programming" title="Computer network programming">network programming</a></i>. Internet socket APIs are usually based on the <a href="Berkeley_sockets" title="Berkeley sockets">Berkeley sockets</a> standard. In the Berkeley sockets standard, sockets are a form of <a href="File_descriptor" title="File descriptor">file descriptor</a>, due to the <a href="Unix_philosophy" title="Unix philosophy">Unix philosophy</a> that "everything is a file", and the analogies between sockets and files. Both have functions to read, write, open, and close. In practice, the differences strain the analogy, and different interfaces (send and receive) are used on a socket. In <a href="Inter-process_communication" title="Inter-process communication">inter-process communication</a>, each end generally has its own socket.

</p><p>In the standard Internet protocols TCP and UDP, a socket address is the combination of an <a href="IP_address" title="IP address">IP address</a> and a <a href="Port_number" class="mw-redirect" title="Port number">port number</a>, much like one end of a telephone connection is the combination of a <a href="Phone_number" class="mw-redirect" title="Phone number">phone number</a> and a particular <a href="Extension_(telephone)" title="Extension (telephone)">extension</a>. Sockets need not have a source address, for example, for only sending data, but if a program <i>binds</i> a socket to a source address, the socket can be used to receive data sent to that address. Based on this address, Internet sockets deliver incoming <a href="Data_packet" class="mw-redirect" title="Data packet">data packets</a> to the appropriate application <a href="Process_(computing)" title="Process (computing)">process</a>.

</p><p><i>Socket</i> often refers specifically to an internet socket or TCP socket. An internet socket is minimally characterized by the following:

</p>

<ul><li>local socket address, consisting of the local IP address and (for TCP and UDP, but not IP) a port number</li>

<li>protocol: A transport protocol, e.g., TCP, UDP, raw IP. This means that (local or remote) endpoints with TCP port 53 and UDP port 53 are distinct sockets, while IP does not have ports.</li>

<li>A socket that has been connected to another socket, e.g., during the establishment of a TCP connection, also has a remote socket address.</li></ul>

<div class="mw-heading mw-heading2"><h2 id="Definition">Definition</h2></div>

<p>The distinctions between a socket (internal representation), socket descriptor (abstract identifier), and socket address (public address) are subtle, and these are not always distinguished in everyday usage. Further, specific definitions of a <i>socket</i> differ between authors. In <a href="IETF" class="mw-redirect" title="IETF">IETF</a> <a href="Request_for_Comments" title="Request for Comments">Request for Comments</a>, <a href="Internet_Standard" title="Internet Standard">Internet Standards</a>, in many textbooks, as well as in this article, the term <i>socket</i> refers to an entity that is uniquely identified by the socket number. In other textbooks,<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> the term <i>socket</i> refers to a local socket address, i.e. a "combination of an IP address and a port number". In the original definition of <i>socket</i> given in RFC 147,<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> as it was related to the <a href="ARPANET" title="ARPANET">ARPA network</a> in 1971, <i>"the socket is specified as a 32-bit number with even sockets identifying receiving sockets and odd sockets identifying sending sockets."</i> Today, however, socket communications are bidirectional.

</p><p>Within the operating system and the application that created a socket, a socket is referred to by a unique integer value called a <i>socket descriptor</i>.

</p>

<div class="mw-heading mw-heading2"><h2 id="Tools">Tools</h2></div>

<p>On Unix-like operating systems and <a href="Microsoft_Windows" title="Microsoft Windows">Microsoft Windows</a>, the command-line tools <a href="Netstat" title="Netstat">netstat</a> or <a href="Iproute2" title="Iproute2">ss</a><i><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> are used to list established sockets and related information.</i>

</p>

<div class="mw-heading mw-heading2"><h2 id="Example">Example</h2></div>

<p>This example, modeled according to the Berkeley socket interface, sends the string "Hello, world!" via <a href="Transmission_Control_Protocol" title="Transmission Control Protocol">TCP</a> to port 80 of the host with address 203.0.113.0. It illustrates the creation of a socket (getSocket), connecting it to the remote host, sending the string, and finally closing the socket:

</p>

<pre>Socket mysocket = getSocket(type = "TCP")

connect(mysocket, address = "203.0.113.0", port = "80")

send(mysocket, "Hello, world!")

close(mysocket)

</pre>

<div class="mw-heading mw-heading2"><h2 id="Types">Types</h2></div>

<p>Several types of Internet socket are available:

</p>

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</style><span class="vanchor"><span class="vanchor-text">Datagram sockets</span></span></dt>

<dd><a href="Connectionless" class="mw-redirect" title="Connectionless">Connectionless</a> sockets, which use <a href="User_Datagram_Protocol" title="User Datagram Protocol">User Datagram Protocol</a> (UDP).<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Each packet sent or received on a datagram socket is individually addressed and routed. Order and reliability are not guaranteed with datagram sockets, so multiple packets sent from one machine or process to another may arrive in any order or might not arrive at all. Special configuration may be required to send <a href="Broadcasting_(networking)" title="Broadcasting (networking)">broadcasts</a> on a datagram socket.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> In order to receive broadcast packets, a datagram socket should not be bound to a specific address, though in some implementations, broadcast packets may also be received when a datagram socket is bound to a specific address.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup></dd>

<dt>Stream sockets</dt>

<dd><a href="Connection-oriented" class="mw-redirect" title="Connection-oriented">Connection-oriented</a> sockets, which use <a href="Transmission_Control_Protocol" title="Transmission Control Protocol">Transmission Control Protocol</a> (TCP), <a href="Stream_Control_Transmission_Protocol" title="Stream Control Transmission Protocol">Stream Control Transmission Protocol</a> (SCTP) or <a href="Datagram_Congestion_Control_Protocol" title="Datagram Congestion Control Protocol">Datagram Congestion Control Protocol</a> (DCCP). A stream socket provides a <a href="Sequenced" class="mw-redirect" title="Sequenced">sequenced</a> and unique flow of error-free data without record boundaries, with well-defined mechanisms for creating and destroying connections and reporting errors. A stream socket transmits data <a href="Reliability_(computer_networking)" title="Reliability (computer networking)">reliably</a>, in order, and with <a href="Out-of-band_data" title="Out-of-band data">out-of-band</a> capabilities. On the Internet, stream sockets are typically implemented using TCP so that applications can run across any networks using TCP/IP protocol.</dd>

<dt>Raw sockets</dt>

<dd>Allow direct sending and receiving of IP packets without any protocol-specific transport layer formatting. With other types of sockets, the <a href="Payload_(computing)" title="Payload (computing)">payload</a> is automatically <a href="Encapsulation_(networking)" title="Encapsulation (networking)">encapsulated</a> according to the chosen transport layer protocol (e.g. TCP, UDP), and the socket user is unaware of the existence of protocol <a href="Header_(computing)" title="Header (computing)">headers</a> that are broadcast with the payload. When reading from a raw socket, the headers are usually included. When transmitting packets from a raw socket, the automatic addition of a header is optional.</dd>

<dd>Most socket <a href="Application_programming_interface" class="mw-redirect" title="Application programming interface">application programming interfaces</a> (APIs), for example, those based on Berkeley sockets, support raw sockets. <a href="Windows_XP" title="Windows XP">Windows XP</a> was released in 2001 with raw socket support implemented in the <a href="Winsock" title="Winsock">Winsock</a> interface, but three years later, Microsoft limited Winsock's raw socket support because of security concerns.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></dd>

<dd>Raw sockets are used in security-related applications like <a href="Nmap" title="Nmap">Nmap</a>. One use case for raw sockets is the implementation of new transport-layer protocols in <a href="User_space" class="mw-redirect" title="User space">user space</a>.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> Raw sockets are typically available in network equipment, and used for <a href="Routing_protocol" title="Routing protocol">routing protocols</a> such as the <a href="Internet_Group_Management_Protocol" title="Internet Group Management Protocol">Internet Group Management Protocol</a> (IGMP) and <a href="Open_Shortest_Path_First" title="Open Shortest Path First">Open Shortest Path First</a> (OSPF), and in the <a href="Internet_Control_Message_Protocol" title="Internet Control Message Protocol">Internet Control Message Protocol</a> (ICMP) used, among other things, by the <a href="Ping_utility" class="mw-redirect" title="Ping utility">ping utility</a>.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup></dd></dl>

<p>Other socket types are implemented over other transport protocols, such as <a href="Systems_Network_Architecture" title="Systems Network Architecture">Systems Network Architecture</a><sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> and <a href="Unix_domain_socket" title="Unix domain socket">Unix domain sockets</a> for internal inter-process communication.

</p>

<div class="mw-heading mw-heading2"><h2 id="Socket_states_in_the_client-server_model">Socket states in the client-server model</h2></div>

<p>Computer processes that provide application services are referred to as <a href="Server_(computing)" title="Server (computing)">servers</a>, and create sockets on startup that are in the <i>listening state</i>. These sockets are waiting for initiatives from <a href="Client_(computing)" title="Client (computing)">client</a> programs.

</p><p>A TCP server may serve several clients concurrently by creating a unique dedicated socket for each client connection in a new child process or processing thread for each client. These are in the <i>established state</i> when a socket-to-socket <a href="Virtual_connection" class="mw-redirect" title="Virtual connection">virtual connection</a> or virtual circuit (VC), also known as a TCP <a href="Session_(computer_science)" title="Session (computer science)">session</a>, is established with the remote socket, providing a duplex <a href="Byte_stream" class="mw-redirect" title="Byte stream">byte stream</a>.

</p><p>A server may create several concurrently established TCP sockets with the same local port number and local IP address, each mapped to its own server-child process, serving its own client process. They are treated as different sockets by the operating system since the remote socket address (the client IP address or port number) is different; i.e. since they have different <a href="#Socket_pairs">socket pair</a> tuples.

</p><p>UDP sockets do not have an <i>established state</i>, because the protocol is <a href="Connectionless" class="mw-redirect" title="Connectionless">connectionless</a>. A UDP server process handles incoming datagrams from all remote clients sequentially through the same socket. UDP sockets are not identified by the remote address, but only by the local address, although each message has an associated remote address that can be retrieved from each datagram with the networking application programming interface (API).

</p>

<div class="mw-heading mw-heading2"><h2 id="Socket_pairs">Socket pairs</h2></div>

<p>Local and remote sockets communicating over TCP are called <b>socket pairs</b>. Each socket pair is described by a unique <a href="4-tuple" class="mw-redirect" title="4-tuple">4-tuple</a> consisting of source and destination IP addresses and port numbers, i.e. of local and remote socket addresses.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> As discussed above, in the TCP case, a socket pair is associated on each end of the connection with a unique 4-tuple.

</p>

<div class="mw-heading mw-heading2"><h2 id="History">History</h2></div>

<p>The term <i>socket</i> dates to the publication of RFC 147 in 1971, when it was used in the ARPANET. Most modern implementations of sockets are based on <a href="Berkeley_sockets" title="Berkeley sockets">Berkeley sockets</a> (1983), and other stacks such as <a href="Winsock" title="Winsock">Winsock</a> (1991). The Berkeley sockets API in the <a href="Berkeley_Software_Distribution" title="Berkeley Software Distribution">Berkeley Software Distribution</a> (BSD), originated with the 4.2BSD <a href="Unix_operating_system" class="mw-redirect" title="Unix operating system">Unix operating system</a> as an API. Only in 1989, however, could <a href="UC_Berkeley" class="mw-redirect" title="UC Berkeley">UC Berkeley</a> release versions of its operating system and networking library free from the licensing constraints of <a href="AT%26T" title="AT&T">AT&T</a>'s copyright-protected <a href="Unix" title="Unix">Unix</a>.

</p><p>In c. 1987, AT&T introduced the <a href="STREAMS" title="STREAMS">STREAMS</a>-based <a href="Transport_Layer_Interface" title="Transport Layer Interface">Transport Layer Interface</a> (TLI) in <a href="UNIX_System_V" title="UNIX System V">UNIX System V</a> Release 3 (SVR3).<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> and continued into Release 4 (SVR4).<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup>

</p><p>Other early implementations were written for <a href="TOPS-20" title="TOPS-20">TOPS-20</a>,<sup id="cite_ref-hcc98_15-0" class="reference"><a href="#cite_note-hcc98-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> <a href="MVS" title="MVS">MVS</a>,<sup id="cite_ref-hcc98_15-1" class="reference"><a href="#cite_note-hcc98-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> <a href="VM_(operating_system)" title="VM (operating system)">VM</a>,<sup id="cite_ref-hcc98_15-2" class="reference"><a href="#cite_note-hcc98-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> <a href="IBM_PC_DOS" title="IBM PC DOS">IBM-DOS</a> (PCIP).<sup id="cite_ref-hcc98_15-3" class="reference"><a href="#cite_note-hcc98-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="Sockets_in_network_equipment">Sockets in network equipment</h2></div>

<p>The socket is primarily a concept used in the <a href="Transport_layer" title="Transport layer">transport layer</a> of the <a href="Internet_protocol_suite" title="Internet protocol suite">Internet protocol suite</a> or <a href="Session_layer" title="Session layer">session layer</a> of the <a href="OSI_model" title="OSI model">OSI model</a>. Networking equipment such as <a href="Router_(computing)" title="Router (computing)">routers</a>, which operate at the <a href="Internet_layer" title="Internet layer">internet layer</a>, and <a href="Network_switch" title="Network switch">switches</a>, which operate at the <a href="Link_layer" title="Link layer">link layer</a>, do not require implementations of the transport layer. However, stateful <a href="Network_firewall" class="mw-redirect" title="Network firewall">network firewalls</a>, <a href="Network_address_translator" class="mw-redirect" title="Network address translator">network address translators</a>, and proxy servers keep track of active socket pairs. In <a href="Multilayer_switch" title="Multilayer switch">multilayer switches</a> and <a href="Quality_of_service" title="Quality of service">quality of service</a> (QoS) support in routers, <a href="Packet_flow" class="mw-redirect" title="Packet flow">packet flows</a> may be identified by extracting information about the socket pairs.

</p><p><a href="Raw_socket" class="mw-redirect" title="Raw socket">Raw sockets</a> are typically available in network equipment and are used for <a href="Routing_protocol" title="Routing protocol">routing protocols</a> such as <a href="IGRP" class="mw-redirect" title="IGRP">IGRP</a> and <a href="OSPF" class="mw-redirect" title="OSPF">OSPF</a>, and for <a href="Internet_Control_Message_Protocol" title="Internet Control Message Protocol">Internet Control Message Protocol</a> (ICMP).

</p>

<ul><li><a href="List_of_TCP_and_UDP_port_numbers" title="List of TCP and UDP port numbers">List of TCP and UDP port numbers</a></li>

<li><a href="Promiscuous_traffic" title="Promiscuous traffic">Promiscuous traffic</a></li>

<li><a href="WebSocket" title="WebSocket">WebSocket</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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<li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text">Cisco Networking Academy Program, CCNA 1 and 2 Companion Guide Revised Third Edition, P.480, <style data-mw-deduplicate="TemplateStyles:r1238218222">

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</style><a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>1-58713-150-1</bdi></span>

</li>

</li>

<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><cite id="CITEREFJack_Wallen2019" class="citation web cs1">Jack Wallen (2019-01-22). <a rel="nofollow" class="external text" href="https://www.linux.com/learn/intro-to-linux/2017/7/introduction-ss-command">"An Introduction to the ss Command"</a>.</cite></span>

</li>

<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><cite id="CITEREFV._S._Bagad,_I._A._Dhotre2008" class="citation cs2">V. S. Bagad, I. A. Dhotre (2008), <i>Computer Networks</i> (5th revised edition, 2010 ed.), Technical Publications Pune, p. 52</cite></span>

</li>

<li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><cite class="citation cs2"><a rel="nofollow" class="external text" href="https://docs.microsoft.com/en-us/windows-hardware/drivers/network/so-broadcast"><i>SO_BROADCAST</i></a>, <a href="Microsoft" title="Microsoft">Microsoft</a><span class="reference-accessdate">, retrieved <span class="nowrap">2019-12-12</span></span></cite></span>

</li>

<li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><cite class="citation cs2"><a rel="nofollow" class="external text" href="https://docs.oracle.com/javase/6/docs/api/java/net/DatagramSocket.html"><i>Class DatagramSocket</i></a>, <a href="Oracle_Corporation" title="Oracle Corporation">Oracle</a><span class="reference-accessdate">, retrieved <span class="nowrap">2019-12-12</span></span></cite></span>

</li>

<li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text">Ian Griffiths for IanG on Tap. 12 August 2004. <a rel="nofollow" class="external text" href="http://www.interact-sw.co.uk/iangblog/2004/08/12/norawsockets">Raw Sockets Gone in XP SP2</a></span>

</li>

<li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://linux.die.net/man/7/raw">"raw(7): IPv4 raw sockets - Linux man page"</a>. <i>die.net</i>.</cite></span>

</li>

<li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.faqs.org/faqs/internet/tcp-ip/raw-ip-faq/">"Raw IP Networking FAQ"</a>. <i>faqs.org</i>.</cite></span>

</li>

<li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20080503074917/http://www-306.ibm.com/software/network/commserver/library/publications/csaix_60/dzgl1m61.htm">"www-306.ibm.com - AnyNet Guide to Sockets over SNA"</a>. Archived from <a rel="nofollow" class="external text" href="http://www-306.ibm.com/software/network/commserver/library/publications/csaix_60/dzgl1m61.htm">the original</a> on 2008-05-03<span class="reference-accessdate">. Retrieved <span class="nowrap">2006-09-07</span></span>.</cite></span>

</li>

<li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://books.google.com/books?id=ptSC4LpwGA0C&pg=PA52&dq=socket+pair+tuple">books.google.com - UNIX Network Programming: The sockets networking API</a></span>

</li>

<li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://books.google.com/books?id=lyY-7VEo9j8C&pg=PA52&dq=socket+pair">books.google.com - Designing BSD Rootkits: An Introduction to Kernel Hacking</a></span>

</li>

<li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text">(<a href="#CITEREFGoodheart1994">Goodheart 1994</a>, p. 11)<span class="error harv-error" style="display: none; font-size:100%"> harv error: no target: CITEREFGoodheart1994 (help)</span></span>

</li>

<li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text">(<a href="#CITEREFGoodheart1994">Goodheart 1994</a>, p. 17)<span class="error harv-error" style="display: none; font-size:100%"> harv error: no target: CITEREFGoodheart1994 (help)</span></span>

</li>

<li id="cite_note-hcc98-15"><span class="mw-cite-backlink">^ <a href="#cite_ref-hcc98_15-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-hcc98_15-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-hcc98_15-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-hcc98_15-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20180617093141/http://www.historyofcomputercommunications.info/Book/9/9.8_TCP-IP-XNS81-83.html">"historyofcomputercommunications.info - Book: 9.8 TCP/IP and XNS 1981 - 1983"</a>. Archived from <a rel="nofollow" class="external text" href="http://www.historyofcomputercommunications.info/Book/9/9.8_TCP-IP-XNS81-83.html">the original</a> on 2018-06-17<span class="reference-accessdate">. Retrieved <span class="nowrap">2011-02-18</span></span>.</cite></span>

</li>

<li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://groups.csail.mit.edu/ana/Publications/PubPDFs/The%20Desktop%20Computer%20as%20a%20Network%20Participant.pdf">The Desktop Computer as a Network Participant.pdf</a> 1985</span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2></div>

<ul><li><cite id="CITEREFJonesOhlund2002" class="citation book cs1">Jones, Anthony; Ohlund, Jim (2002). <i>Network Programming for Microsoft Windows</i>. Microsoft Press. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-7356-1579-9</bdi>.</cite></li></ul>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><a rel="nofollow" class="external text" href="https://www.ibm.com/docs/en/i/7.2?topic=programming-how-sockets-work">How sockets work</a> - IBM documentation</li>

<li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20170409201335/https://pdfs.semanticscholar.org/0858/d27611d7a90c221beb5106e63721aeaed810.pdf">Server Programming with TCP/IP Sockets</a></li>

<li><a rel="nofollow" class="external text" href="http://beej.us/guide/bgnet/">Beej's Guide to Network Programming</a></li>

<li><a rel="nofollow" class="external text" href="http://java.sun.com/docs/books/tutorial/networking/overview/networking.html">Java Tutorials: Networking basics</a></li>

<li><a rel="nofollow" class="external text" href="http://metacpan.org/module/Net::RawIP">Net::RawIP; module for Perl applications.</a> Created by <a rel="nofollow" class="external text" href="https://web.archive.org/web/20050623074557/http://www.ic.al.lg.ua/~ksv/">Sergey Kolychev</a>.</li>

<li><a rel="nofollow" class="external text" href="http://sock-raw.org/papers/sock_raw">SOCK_RAW Demystified: article describing inner workings of Raw Sockets</a></li>

<li><a rel="nofollow" class="external text" href="http://www.pdbuchan.com/rawsock/rawsock.html">C language examples of Linux raw sockets for IPv4 and IPv6</a> - David Buchan's C language examples of IPv4 and IPv6 raw sockets for Linux.</li></ul>

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</style><div id="Inter-process_communication278" style="font-size:114%;margin:0 4em"><a href="Inter-process_communication" title="Inter-process communication">Inter-process communication</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div><a href="Data" title="Data">Data</a> exchange among <a href="Thread_(computing)" title="Thread (computing)">threads</a> in <a href="Computer_program" title="Computer program">computer programs</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Methods</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Mmap" title="Mmap">Memory-mapped file</a></li>

<li><a href="Message_passing" title="Message passing">Message passing</a></li>

<li><a href="Message_queue" title="Message queue">Message queue and mailbox</a></li>

<li><a href="Named_pipe" title="Named pipe">Named pipe</a></li>

<li><a href="Anonymous_pipe" title="Anonymous pipe">Anonymous pipe</a></li>

<li><a href="Semaphore_(programming)" title="Semaphore (programming)">Semaphore</a></li>

<li><a href="Shared_memory" title="Shared memory">Shared memory</a></li>

<li><a href="Signal_(IPC)" title="Signal (IPC)">Signal</a></li>

<li>Sockets

<ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Communication_protocol" title="Communication protocol">Protocols</a><br>and <a href="Technical_standard" title="Technical standard">standards</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Apple_event" title="Apple event">Apple events</a></li>

<li><a href="Common_Object_Request_Broker_Architecture" title="Common Object Request Broker Architecture">CORBA</a></li>

<li><a href="OpenBinder" title="OpenBinder">OpenBinder</a></li>

<li><a href="POSIX" title="POSIX">POSIX</a> (various methods)</li>

<li><a href="Apache_Thrift" title="Apache Thrift">Thrift</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Library_(computing)" title="Library (computing)">Software libraries</a><br>and <a href="Software_framework" title="Software framework">frameworks</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Libevent" title="Libevent">libevent</a></li>

<li><a href="SIMPL" title="SIMPL">SIMPL</a></li>

</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-02-22" href="https://en.wikipedia.org/wiki/?title=Network_socket&oldid=1277071107">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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