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Available in 7 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-7" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">7 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Secure_Socket_Tunneling_Protocol" title="Secure Socket Tunneling Protocol – Czech" lang="cs" hreflang="cs" data-title="Secure Socket Tunneling Protocol" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Secure_Socket_Tunneling_Protocol" title="Secure Socket Tunneling Protocol – German" lang="de" hreflang="de" data-title="Secure Socket Tunneling Protocol" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%A7%D8%B3%E2%80%8C%D8%A7%D8%B3%E2%80%8C%D8%AA%DB%8C%E2%80%8C%D9%BE%DB%8C" title="اس‌اس‌تی‌پی – Persian" lang="fa" hreflang="fa" data-title="اس‌اس‌تی‌پی" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Secure_Socket_Tunneling_Protocol" title="Secure Socket Tunneling Protocol – French" lang="fr" hreflang="fr" data-title="Secure Socket Tunneling Protocol" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/SSTP" title="SSTP – Italian" lang="it" hreflang="it" data-title="SSTP" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/Secure_Socket_Tunneling_Protocol" title="Secure Socket Tunneling Protocol – Serbian" lang="sr" hreflang="sr" data-title="Secure Socket Tunneling Protocol" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/Secure_Socket_Tunneling_Protocol" title="Secure Socket Tunneling Protocol – Ukrainian" lang="uk" hreflang="uk" data-title="Secure Socket Tunneling Protocol" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q666515#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Secure_Socket_Tunneling_Protocol" title="View the content page [c]" 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</div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Form of virtual private network tunnel</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Not to be confused with <a href="/wiki/Simple_Symmetric_Transport_Protocol" title="Simple Symmetric Transport Protocol">Simple Symmetric Transport Protocol</a>.</div> <p>In <a href="/wiki/Computer_networking" class="mw-redirect" title="Computer networking">computer networking</a>, <b>Secure Socket Tunneling Protocol</b> (<b>SSTP</b>) is a form of <a href="/wiki/Virtual_private_network" title="Virtual private network">virtual private network</a> (VPN) tunnel that provides a mechanism to transport <a href="/wiki/Point-to-Point_Protocol" title="Point-to-Point Protocol">Point-to-Point Protocol</a> (PPP) traffic through an <a href="/wiki/Transport_Layer_Security" title="Transport Layer Security">SSL/TLS</a> channel. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Protocol">Protocol</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Secure_Socket_Tunneling_Protocol&action=edit&section=1" title="Edit section: Protocol"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>SSL/TLS provides transport-level security with key negotiation, <a href="/wiki/Encryption" title="Encryption">encryption</a> and traffic integrity checking. The use of SSL/TLS over <a href="/wiki/Transmission_Control_Protocol" title="Transmission Control Protocol">TCP</a> port 443 (by default; port can be changed) allows SSTP to pass through virtually all <a href="/wiki/Firewall_(computing)" title="Firewall (computing)">firewalls</a> and <a href="/wiki/Proxy_server" title="Proxy server">proxy servers</a> except for authenticated web proxies.<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> </p><p>SSTP servers must be <a href="/wiki/Authentication" title="Authentication">authenticated</a> during the SSL/TLS phase. SSTP clients can optionally be authenticated during the SSL/TLS phase and must be authenticated in the PPP phase. The use of PPP allows support for common authentication methods, such as <a href="/wiki/EAP-TLS" class="mw-redirect" title="EAP-TLS">EAP-TLS</a> and <a href="/wiki/MS-CHAP" title="MS-CHAP">MS-CHAP</a>. </p><p>SSTP is available for <a href="/wiki/Linux" title="Linux">Linux</a>, <a href="/wiki/BSD" class="mw-redirect" title="BSD">BSD</a>, and <a href="/wiki/Windows" class="mw-redirect" title="Windows">Windows</a>.<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> </p><p>SSTP was introduced in 2007<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> and available on <a href="/wiki/Windows_Vista_SP1" class="mw-redirect" title="Windows Vista SP1">Windows Vista SP1</a> and later, in <a href="/wiki/MikroTik" title="MikroTik">RouterOS</a> since version 5.0, and in <a href="/wiki/IIJ_SEIL" class="mw-redirect" title="IIJ SEIL">SEIL</a> since its firmware version 3.50. It is fully integrated with the RRAS architecture in these operating systems, allowing its use with <a href="/wiki/Winlogon" title="Winlogon">Winlogon</a> or <a href="/wiki/Smart-card" class="mw-redirect" title="Smart-card">smart-card</a> authentication, remote-access policies and the Windows VPN client.<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> The protocol is also used by <a href="/wiki/Windows_Azure" class="mw-redirect" title="Windows Azure">Windows Azure</a> for Point-to-Site Virtual Network.<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> </p><p>SSTP is intended only for remote client access, it generally does not support site-to-site VPN tunnels.<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> </p><p>SSTP suffers from the same performance limitations as any other IP-over-TCP tunnel. In general, performance will be acceptable only as long as there is sufficient excess bandwidth on the un-tunneled network link to guarantee that the tunneled TCP timers do not expire. If this becomes untrue, performance falls off dramatically due to the <a href="/wiki/TCP_meltdown_problem" class="mw-redirect" title="TCP meltdown problem">TCP meltdown problem</a>.<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><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> </p><p>SSTP supports user authentication only; it does not support device authentication or computer authentication. </p> <div class="mw-heading mw-heading2"><h2 id="Packet_structure">Packet structure</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Secure_Socket_Tunneling_Protocol&action=edit&section=2" title="Edit section: Packet structure"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The following header structure is common to all types of SSTP packets:<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> </p> <table class="wikitable" style="text-align :center"> <caption>SSTP header </caption> <tbody><tr> <th>Bit offset</th> <th colspan="8">Bits 0–7</th> <th colspan="7">8–14</th> <th>15</th> <th colspan="16">16–31 </th></tr> <tr> <th>0 </th> <td colspan="8">Version</td> <td colspan="7">Reserved</td> <td colspan="1">C</td> <td colspan="16">Length </td></tr> <tr> <th>32+ </th> <td colspan="32">Data </td></tr></tbody></table> <ul><li>Version (8 bits) – communicates and negotiates the version of SSTP that is used.</li> <li>Reserved (7 bits) – reserved for future use.</li> <li>C (1 bit) – control bit indicating whether the SSTP packet represents an SSTP control packet or an SSTP data packet. This bit is set if the SSTP packet is a control packet.</li> <li>Length (16 bits) – packet length field, composed of two values: a Reserved portion and a Length portion.</li></ul> <dl><dd><ul><li>Reserved (4 bits) – reserved for future use.</li> <li>Length (12 bits) – contains the length of the entire SSTP packet, including the SSTP header.</li></ul></dd></dl> <ul><li>Data (variable) – when control bit C is set, this field contains an SSTP control message. Otherwise, the data field would contain a higher-level protocol. At the moment, this can only be <a href="/wiki/Point-to-Point_Protocol" title="Point-to-Point Protocol">PPP</a>.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Control_message">Control message</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Secure_Socket_Tunneling_Protocol&action=edit&section=3" title="Edit section: Control message"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The data field of the SSTP header contains an SSTP control message only when the header's Control bit C is set. </p> <table class="wikitable" style="text-align:center"> <caption>SSTP control message </caption> <tbody><tr> <th>Bit offset</th> <th colspan="16">Bits 0–15</th> <th colspan="16">16–31 </th></tr> <tr> <th>0 </th> <td colspan="16">Message type</td> <td colspan="16">Attributes count </td></tr> <tr> <th>32+ </th> <td colspan="32">Attributes </td></tr></tbody></table> <ul><li>Message type (16 bits) – specifies the type of SSTP control message being communicated. This dictates the number and types of attributes that can be carried in the SSTP control packet.</li> <li>Attributes count (16 bits) – specifies the number of attributes appended to the SSTP control message.</li> <li>Attributes (variable) – contains a list of attributes associated with the SSTP control message. The number of attributes is specified by the Attributes count field.</li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Secure_Socket_Tunneling_Protocol&action=edit&section=4" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/AuthIP" title="AuthIP">AuthIP</a></li> <li><a href="/wiki/L2TP#L2TP.2FIPsec" class="mw-redirect" title="L2TP">L2TP/IPsec</a></li> <li><a href="/wiki/HTTPS" title="HTTPS">HTTPS</a></li> <li><a href="/wiki/OpenVPN" title="OpenVPN">OpenVPN</a></li> <li><a href="/wiki/OpenConnect" title="OpenConnect">OpenConnect VPN</a></li> <li><a href="/wiki/PPTP" class="mw-redirect" title="PPTP">PPTP</a></li> <li><a href="/wiki/SoftEther_VPN" title="SoftEther VPN">SoftEther VPN</a>, an open-source VPN server program which supports SSTP-VPN protocol.</li> <li><a href="/wiki/WireGuard" title="WireGuard">WireGuard</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Secure_Socket_Tunneling_Protocol&action=edit&section=5" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFJain2007" class="citation web cs1">Jain, Samir (2007-01-17). <a rel="nofollow" class="external text" href="http://blogs.technet.com/b/rrasblog/archive/2007/01/17/sstp-faq-part-2-client-specific.aspx">"SSTP FAQ - 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Vol. 6011. p. 60110H. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2005SPIE.6011..138H">2005SPIE.6011..138H</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1117%2F12.630496">10.1117/12.630496</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:8945952">8945952</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Understanding+TCP+over+TCP%3A+effects+of+TCP+tunneling+on+end-to-end+throughput+and+latency&rft.btitle=Performance%2C+Quality+of+Service%2C+and+Control+of+Next-Generation+Communication+and+Sensor+Networks+III&rft.pages=60110H&rft.date=2005-10&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A8945952%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1117%2F12.630496&rft_id=info%3Abibcode%2F2005SPIE.6011..138H&rft.au=Honda%2C+Osamu&rft.au=Ohsaki%2C+Hiroyuki&rft.au=Imase%2C+Makoto&rft.au=Ishizuka%2C+Mika&rft.au=Murayama%2C+Junichi&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASecure+Socket+Tunneling+Protocol" class="Z3988"></span></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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://technet.microsoft.com/en-us/subscriptions/cc247338.aspx">"MS-SSTP: Secure Socket Tunneling Protocol (SSTP)"</a>. 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href="https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-sstp/c50ed240-56f3-4309-8e0c-1644898f0ea8">[MS-SSTP]: Secure Socket Tunneling Protocol (SSTP)</a> by <a href="/wiki/Microsoft_Open_Specification_Promise" title="Microsoft Open Specification Promise">Microsoft Open Specification Promise</a></li> <li><a rel="nofollow" class="external text" href="http://blogs.technet.com/rrasblog/archive/tags/SSTP/default.aspx">RRAS Technet Blog</a></li> <li><a rel="nofollow" class="external text" href="http://www.techworld.com/networking/news/index.cfm?newsID=7814&pagtype=all">Microsoft develops new tunneling protocol</a></li> <li><a rel="nofollow" class="external text" href="https://blogs.technet.microsoft.com/rrasblog/2007/01/10/how-sstp-based-vpn-connection-works/">How SSTP based VPN connection works</a></li> <li><a rel="nofollow" class="external text" href="http://www.hsc.fr/ressources/outils/sstoper/index.html.en">HSC's SSTP Client for Linux</a></li> <li><a rel="nofollow" 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.navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Virtual_private_networking" style="padding:3px"><table class="nowraplinks mw-collapsible expanded navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Virtual_private_network" title="Template:Virtual private network"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Virtual_private_network" title="Template talk:Virtual private network"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Virtual_private_network" title="Special:EditPage/Template:Virtual private network"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Virtual_private_networking" style="font-size:114%;margin:0 4em"><a href="/wiki/Virtual_private_network" title="Virtual private network">Virtual private networking</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Communication_protocol" title="Communication protocol">Communication protocols</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Datagram_Transport_Layer_Security" title="Datagram Transport Layer Security">DTLS</a></li> <li><a href="/wiki/DirectAccess" title="DirectAccess">DirectAccess</a></li> <li><a href="/wiki/Ethernet_VPN" title="Ethernet VPN">EVPN</a></li> <li><a href="/wiki/IPsec" title="IPsec">IPsec</a></li> <li><a href="/wiki/Layer_2_Forwarding_Protocol" title="Layer 2 Forwarding Protocol">L2F</a></li> <li><a href="/wiki/Layer_2_Tunneling_Protocol" title="Layer 2 Tunneling Protocol">L2TP</a></li> <li><a href="/wiki/L2TPv3" title="L2TPv3">L2TPv3</a></li> <li><a href="/wiki/Point-to-Point_Tunneling_Protocol" title="Point-to-Point Tunneling Protocol">PPTP</a></li> <li><a class="mw-selflink selflink">SSTP</a></li> <li><a href="/wiki/Split_tunneling" title="Split tunneling">Split tunneling</a></li> <li><a href="/wiki/Transport_Layer_Security" title="Transport Layer Security">SSL/TLS</a></li> <li>(<a href="/wiki/Opportunistic_encryption" title="Opportunistic encryption">Opportunistic</a>: <a href="/wiki/Tcpcrypt" title="Tcpcrypt">tcpcrypt</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Connection applications</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="/wiki/FreeLAN" title="FreeLAN">FreeLAN</a></li> <li><a href="/wiki/FreeS/WAN" title="FreeS/WAN">FreeS/WAN</a></li> <li><a href="/wiki/Libreswan" title="Libreswan">Libreswan</a></li> <li><a href="/wiki/N2n" title="N2n">n2n</a></li> <li><a href="/wiki/OpenConnect" title="OpenConnect">OpenConnect</a></li> <li><a href="/wiki/OpenIKED" title="OpenIKED">OpenIKED</a></li> <li><a href="/wiki/Openswan" title="Openswan">Openswan</a></li> <li><a href="/wiki/OpenVPN" title="OpenVPN">OpenVPN</a></li> <li><a href="/wiki/Social_VPN" title="Social VPN">Social VPN</a></li> <li><a href="/wiki/SoftEther_VPN" title="SoftEther VPN">SoftEther VPN</a></li> <li><a href="/wiki/StrongSwan" title="StrongSwan">strongSwan</a></li> <li><a href="/wiki/Tcpcrypt" title="Tcpcrypt">tcpcrypt</a></li> <li><a href="/wiki/Tinc_(protocol)" title="Tinc (protocol)">tinc</a></li> <li><a href="/wiki/VTun" title="VTun">VTun</a></li> <li><a href="/wiki/WireGuard" title="WireGuard">WireGuard</a></li> <li><a href="/wiki/Shadowsocks" title="Shadowsocks">Shadowsocks</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Enterprise_software" title="Enterprise software">Enterprise software</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Avast_SecureLine_VPN" title="Avast SecureLine VPN">Avast SecureLine VPN</a></li> <li><a href="/wiki/Check_Point_VPN-1" class="mw-redirect" title="Check Point VPN-1">Check Point VPN-1</a></li> <li><a href="/wiki/LogMeIn_Hamachi" title="LogMeIn Hamachi">LogMeIn Hamachi</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Risk vectors</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="/wiki/Content-control_software" class="mw-redirect" title="Content-control software">Content-control software</a></li> <li><a href="/wiki/Deep_content_inspection" title="Deep content inspection">Deep content inspection</a></li> <li><a href="/wiki/Deep_packet_inspection" title="Deep packet inspection">Deep packet inspection</a></li> <li><a href="/wiki/IP_address_blocking" title="IP address blocking">IP address blocking</a></li> <li><a href="/wiki/Network_enumeration" title="Network enumeration">Network enumeration</a></li> <li><a href="/wiki/Stateful_firewall" title="Stateful firewall">Stateful firewall</a></li> <li><a href="/wiki/TCP_reset_attack" title="TCP reset attack">TCP reset attack</a></li> <li><a href="/wiki/VPN_blocking" title="VPN blocking">VPN blocking</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/VPN_service" title="VPN service">VPN Services</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/Avast" title="Avast">Avast</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/HMA_(VPN)" title="HMA (VPN)">HMA</a></li> <li><a href="/wiki/Avast_SecureLine_VPN" title="Avast SecureLine VPN">SecureLine</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/Kape_Technologies" class="mw-redirect" title="Kape Technologies">Kape Technologies</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li>CyberGhost</li> <li><a href="/wiki/ExpressVPN" title="ExpressVPN">ExpressVPN</a></li> <li><a href="/wiki/Private_Internet_Access" title="Private Internet Access">Private Internet Access</a></li> <li>Zenmate</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/McAfee" title="McAfee">McAfee</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/TunnelBear" title="TunnelBear">TunnelBear</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em">Tesonet</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/NordVPN" title="NordVPN">NordVPN</a></li> <li><a href="/wiki/NordLayer" title="NordLayer">NordLayer</a></li> <li><a href="/wiki/Surfshark" class="mw-redirect" title="Surfshark">Surfshark</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/Ziff_Davis" title="Ziff Davis">Ziff Davis</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IPVanish" title="IPVanish">IPVanish</a></li> <li><a href="/wiki/StrongVPN" class="mw-redirect" title="StrongVPN">StrongVPN</a></li></ul> </div></td></tr></tbody></table><div> <ul><li><a href="/wiki/Hola_(VPN)" title="Hola (VPN)">Hola</a></li> <li><a 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