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diff --git a/static/freebsd/man4/ng_vjc.4 3.html b/static/freebsd/man4/ng_vjc.4 3.html deleted file mode 100644 index b5fe1671..00000000 --- a/static/freebsd/man4/ng_vjc.4 3.html +++ /dev/null @@ -1,179 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">NG_VJC(4)</td> - <td class="head-vol">Device Drivers Manual</td> - <td class="head-rtitle">NG_VJC(4)</td> - </tr> -</table> -<div class="manual-text"> -<section class="Sh"> -<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> -<p class="Pp"><code class="Nm">ng_vjc</code> — <span class="Nd">Van - Jacobson compression netgraph node type</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> -<p class="Pp"><code class="In">#include - <<a class="In">sys/types.h</a>></code> - <br/> - <code class="In">#include <<a class="In">netinet/in.h</a>></code> - <br/> - <code class="In">#include <<a class="In">netinet/in_systm.h</a>></code> - <br/> - <code class="In">#include <<a class="In">netinet/ip.h</a>></code> - <br/> - <code class="In">#include <<a class="In">net/slcompress.h</a>></code> - <br/> - <code class="In">#include - <<a class="In">netgraph/ng_vjc.h</a>></code></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp">The <code class="Nm">vjc</code> node type performs Van Jacobson - compression, which is used over PPP, SLIP, and other point-to-point IP - connections to compress TCP packet headers. The <code class="Dv">ip</code> - hook represents the uncompressed side of the node, while the - <code class="Dv">vjcomp</code>, <code class="Dv">vjuncomp</code>, and - <code class="Dv">vjip</code> hooks represent the compressed side of the - node. Packets received on the <code class="Dv">ip</code> will be compressed - or passed through as appropriate. Packets received on the other three hooks - will be uncompressed as appropriate. This node also supports “always - pass through” mode in either direction.</p> -<p class="Pp">Van Jacobson compression only applies to TCP packets. Only - “normal” (i.e., common case) TCP packets are actually - compressed. These are output on the <code class="Dv">vjcomp</code> hook. - Other TCP packets are run through the state machine but not compressed; - these appear on the <code class="Dv">vjuncomp</code> hook. Other non-TCP IP - packets are forwarded unchanged to <code class="Dv">vjip</code>.</p> -<p class="Pp">When connecting to a <a class="Xr">ng_ppp(4)</a> node, the - <code class="Dv">ip</code>, <code class="Dv">vjuncomp</code>, - <code class="Dv">vjcomp</code>, and <code class="Dv">vjip</code> hooks - should be connected to the <a class="Xr">ng_ppp(4)</a> node's - <code class="Dv">vjc_ip</code>, <code class="Dv">vjc_vjcomp</code>, - <code class="Dv">vjc_vjuncomp</code>, and <code class="Dv">vjc_ip</code> - hooks, respectively.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HOOKS"><a class="permalink" href="#HOOKS">HOOKS</a></h1> -<p class="Pp">This node type supports the following hooks:</p> -<dl class="Bl-tag"> - <dt id="ip"><var class="Va">ip</var></dt> - <dd>Upstream (uncompressed) IP packets.</dd> - <dt id="vjcomp"><var class="Va">vjcomp</var></dt> - <dd>Downstream compressed TCP packets.</dd> - <dt id="vjuncomp"><var class="Va">vjuncomp</var></dt> - <dd>Downstream uncompressed TCP packets.</dd> - <dt id="vjip"><var class="Va">vjip</var></dt> - <dd>Downstream uncompressed IP packets.</dd> -</dl> -</section> -<section class="Sh"> -<h1 class="Sh" id="CONTROL_MESSAGES"><a class="permalink" href="#CONTROL_MESSAGES">CONTROL - MESSAGES</a></h1> -<p class="Pp">This node type supports the generic control messages, plus the - following:</p> -<dl class="Bl-tag"> - <dt id="NGM_VJC_SET_CONFIG"><a class="permalink" href="#NGM_VJC_SET_CONFIG"><code class="Dv">NGM_VJC_SET_CONFIG</code></a> - (<code class="Ic">setconfig</code>)</dt> - <dd>This command resets the compression state and configures it according to - the supplied <code class="Dv">struct ngm_vjc_config</code> argument. This - structure contains the following fields: - <div class="Bd Pp Bd-indent Li"> - <pre>struct ngm_vjc_config { - u_char enableComp; /* Enable compression */ - u_char enableDecomp; /* Enable decompression */ - u_char maxChannel; /* Number of outgoing channels - 1 */ - u_char compressCID; /* OK to compress outgoing CID's */ -};</pre> - </div> - <p class="Pp">When <code class="Dv">enableComp</code> is set to zero, all - packets received on the <code class="Dv">ip</code> hook are forwarded - unchanged out the <code class="Dv">vjip</code> hook. Similarly, when - <code class="Dv">enableDecomp</code> is set to zero, all packets - received on the <code class="Dv">vjip</code> hook are forwarded - unchanged out the <code class="Dv">ip</code> hook, and packets are not - accepted on the <code class="Dv">vjcomp</code> and - <code class="Dv">vjuncomp</code> hooks. When a node is first created, - both compression and decompression are disabled and the node is - therefore operating in bi-directional “pass through” - mode.</p> - <p class="Pp">When enabling compression, <code class="Dv">maxChannel</code> - should be set to the number of outgoing compression channels minus one, - and is a value between 3 and 15, inclusive. The - <code class="Dv">compressCID</code> field indicates whether it is OK to - compress the CID header field for outgoing compressed TCP packets. This - value should be zero unless either (a) it is not possible for an - outgoing frame to be lost, or (b) lost frames can be reliably detected - and immediately reported to the peer's decompression engine (see - <code class="Dv">NGM_VJC_RECV_ERROR</code> below).</p> - </dd> - <dt id="NGM_VJC_GET_STATE"><a class="permalink" href="#NGM_VJC_GET_STATE"><code class="Dv">NGM_VJC_GET_STATE</code></a> - (<code class="Ic">getstate</code>)</dt> - <dd>This command returns the node's current state described by the - <code class="Dv">struct slcompress</code> structure, which is defined in - <code class="In"><<a class="In">net/slcompress.h</a>></code>.</dd> - <dt id="NGM_VJC_CLR_STATS"><a class="permalink" href="#NGM_VJC_CLR_STATS"><code class="Dv">NGM_VJC_CLR_STATS</code></a> - (<code class="Ic">clrstats</code>)</dt> - <dd>Clears the node statistics counters. Statistics are also cleared whenever - the <code class="Dv">enableComp</code> or - <code class="Dv">enableDecomp</code> fields are changed from zero to one - by a <code class="Dv">NGM_VJC_SET_CONFIG</code> control message.</dd> - <dt id="NGM_VJC_RECV_ERROR"><a class="permalink" href="#NGM_VJC_RECV_ERROR"><code class="Dv">NGM_VJC_RECV_ERROR</code></a> - (<code class="Ic">recverror</code>)</dt> - <dd>When the peer has CID header field compression enabled, this message must - be sent to the local <code class="Nm">vjc</code> node immediately after - detecting that a received frame has been lost, due to a bad checksum or - for any other reason. Failing to do this can result in corrupted TCP - stream data.</dd> -</dl> -</section> -<section class="Sh"> -<h1 class="Sh" id="SHUTDOWN"><a class="permalink" href="#SHUTDOWN">SHUTDOWN</a></h1> -<p class="Pp">This node shuts down upon receipt of a - <code class="Dv">NGM_SHUTDOWN</code> control message, or when all hooks have - been disconnected.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE - ALSO</a></h1> -<p class="Pp"><a class="Xr">netgraph(4)</a>, <a class="Xr">ng_iface(4)</a>, - <a class="Xr">ng_ppp(4)</a>, <a class="Xr">ngctl(8)</a></p> -<p class="Pp"><cite class="Rs"><span class="RsA">V. Jacobson</span>, - <span class="RsT">Compressing TCP/IP Headers</span>, <span class="RsO">RFC - 1144</span>.</cite></p> -<p class="Pp"><cite class="Rs"><span class="RsA">G. McGregor</span>, - <span class="RsT">The PPP Internet Control Protocol (IPCP)</span>, - <span class="RsO">RFC 1332</span>.</cite></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> -<p class="Pp">The <code class="Nm">ng_vjc</code> node type was implemented in - <span class="Ux">FreeBSD 4.0</span>.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> -<p class="Pp"><span class="An">Archie Cobbs</span> - <<a class="Mt" href="mailto:archie@FreeBSD.org">archie@FreeBSD.org</a>></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1> -<p class="Pp">As the initialization routine in the kernel implementation of Van - Jacobson compression initializes both compression and decompression at once, - this node does not allow compression and decompression to be enabled in - separate operations. In order to enable one when the other is already - enabled, first both must be disabled, then both enabled. This of course - resets the node state. This restriction may be lifted in a later - version.</p> -<p class="Pp">When built as a loadable kernel module, this module includes the - file <span class="Pa">net/slcompress.c</span>. Although loading the module - should fail if <span class="Pa">net/slcompress.c</span> already exists in - the kernel, currently it does not, and the duplicate copies of the file do - not interfere. However, this may change in the future.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">January 19, 1999</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |