href="howto/auth.html">Authentication, Authorization, and Access
Control</a>
</dd>
-
+
<dt><a name="algorithm" id="algorithm">Algorithm</a></dt>
<dd>An unambiguous formula or set of rules for solving a problem in a finite
number of steps. Algorithms for encryption are usually called
<dfn>Ciphers</dfn>.
</dd>
-
+
<dt><a name="apacheextensiontool" id="apacheextensiontool">APache
eXtension Tool</a> <a name="apxs" id="apxs">(apxs)</a></dt>
<dd>A perl script that aids in compiling <glossary
Gateway Interface</a> <a name="cgi" id="cgi">(CGI)</a></dt>
<dd>A standard definition for an interface between a web server and an
external program that allows the external program to service requests.
- The interface was originally defined by <a
- href="http://hoohoo.ncsa.uiuc.edu/cgi/overview.html">NCSA</a> but there
- is also an <a href="http://cgi-spec.golux.com/">RFC project</a>.<br />
+ There is an <a href="http://www.ietf.org/rfc/rfc3875">Informational
+ RFC</a> which covers the specifics.<br />
See: <a href="howto/cgi.html">Dynamic Content with CGI</a>
</dd>
channels over HTTP. It can be used to encapsulate other protocols, such as
the SSL protocol.
</dd>
-
+
<dt><a name="context" id="context">Context</a></dt>
<dd>An area in the <glossary ref="configurationfile">configuration
files</glossary> where certain types of <glossary
<em>Certificate</em>.<br />
See: <a href="ssl/">SSL/TLS Encryption</a>
</dd>
-
+
<dt><a name="directive" id="directive">Directive</a></dt>
<dd>A configuration command that controls one or more aspects of Apache's
behavior. Directives are placed in the <glossary
See: <a href="filter.html">Filters</a>
</dd>
- <dt><a name="fully-qualifieddomain-name"
+ <dt><a name="fully-qualifieddomain-name"
id="fully-qualifieddomain-name">Fully-Qualified Domain-Name</a>
<a name="fqdn" id="fqdn">(FQDN)</a></dt>
<dd>The unique name of a network entity, consisting of a hostname and a
domain name that can resolve to an IP address. For example,
<code>www</code> is a hostname, <code>example.com</code> is a domain name,
and <code>www.example.com</code> is a fully-qualified domain name.
- </dd>
-
+ </dd>
+
<dt><a name="handler" id="handler">Handler</a></dt>
<dd>An internal Apache representation of the action to be performed when a
file is called. Generally, files have implicit handlers, based on the file
<dd>The part of the <glossary ref="http">HTTP</glossary> request and
response that is sent before the actual content, and that contains
meta-information describing the content.
- </dd>
-
- <dt><a name="htaccess" id="htaccess">.htaccess</a></dt>
+ </dd>
+
+ <dt><a name="htaccess" id="htaccess">.htaccess</a></dt>
<dd>A <glossary ref="configurationfile">configuration file</glossary> that
is placed inside the web tree and applies configuration <glossary
ref="directive">directives</glossary> to the directory where it is
communication mechanism on the World Wide Web. This is actually just HTTP
over <glossary ref="ssl">SSL</glossary>.<br />
See: <a href="ssl/">SSL/TLS Encryption</a>
- </dd>
+ </dd>
<dt><a name="method" id="method">Method</a></dt>
<dd>In the context of <glossary ref="http">HTTP</glossary>, an action to
perform on a resource, specified on the request line by the client. Some
of the methods available in HTTP are <code>GET</code>, <code>POST</code>,
and <code>PUT</code>.
- </dd>
-
+ </dd>
+
<dt><a name="messagedigest" id="messagedigest">Message Digest</a></dt>
<dd>A hash of a message, which can be used to verify that the contents of
the message have not been altered in transit.<br />
sign outgoing ones.<br />
See: <a href="ssl/">SSL/TLS Encryption</a>
</dd>
-
+
<dt><a name="proxy" id="proxy">Proxy</a></dt>
<dd>An intermediate server that sits between the client and the <em>origin
server</em>. It accepts requests from clients, transmits those requests
expressions are useful in Apache because they let you apply certain
attributes against collections of files or resources in very flexible ways
- for example, all .gif and .jpg files under any "images" directory could
- be written as "<code>/images/.*(jpg|gif)$</code>". Apache uses Perl
- Compatible Regular Expressions provided by the <a
- href="http://www.pcre.org/">PCRE</a> library.
+ be written as "<code>/images/.*(jpg|gif)$</code>". In places where
+ regular expressions are used to replace strings, the special variables
+ $1 ... $9 contain backreferences to the grouped parts (in parentheses) of
+ the matched expression. The special variable $0 contains a backreference
+ to the whole matched expression. To write a literal dollar sign in a
+ replacement string, it can be escaped with a backslash. Historically, the
+ variable & could be used as alias for $0 in some places. This is no
+ longer possible since version 2.3.6. Apache uses Perl Compatible Regular
+ Expressions provided by the <a href="http://www.pcre.org/">PCRE</a>
+ library. You can find more documentation about PCRE's regular expression
+ syntax at that site, or at
+ <a href="http://en.wikipedia.org/wiki/PCRE">Wikipedia</a>.
</dd>
<dt><a name="reverseproxy" id="reverseproxy">Reverse Proxy</a></dt>
as if it is an <em>origin server</em>. This is useful to hide the real
origin server from the client for security reasons, or to load balance.
</dd>
-
+
<dt><a name="securesocketslayer" id="securesocketslayer">Secure Sockets
Layer</a> <a name="ssl" id="ssl">(SSL)</a></dt>
<dd>A protocol created by Netscape Communications Corporation for general
See: <a href="ssl/">SSL/TLS Encryption</a>
</dd>
+ <dt><a name="servernameindication" id="servernameindication">Server Name
+ Indication</a> <a name="sni" id="sni">(SNI)</a></dt>
+ <dd>An SSL function that allows passing the desired server
+ hostname in the initial SSL handshake message, so that the web
+ server can select the correct virtual host configuration to use
+ in processing the SSL handshake. It was added to SSL starting
+ with the TLS extensions, RFC 3546. <br />
+ See: <a href="ssl/ssl_faq.html">the SSL FAQ</a>
+ and <a href="http://www.ietf.org/rfc/rfc3546.txt">RFC 3546</a>
+ </dd>
+
<dt><a name="serversideincludes" id="serversideincludes">Server Side
Includes</a> <a name="ssi" id="ssi">(SSI)</a></dt>
<dd>A technique for embedding processing directives inside HTML files.<br />
Young
</dd>
+ <dt><a name="subrequest" id="subrequest">Subrequest</a></dt>
+ <dd>Apache provides a subrequest API to modules that allows other
+ filesystem or URL paths to be partially or fully evaluated by
+ the server. Example consumers of this API are
+ <directive module="mod_dir">DirectoryIndex</directive>,
+ <module>mod_autoindex</module>, and <module>mod_include</module>.
+ </dd>
+
<dt><a name="symmetriccryptophraphy" id="symmetriccryptophraphy">Symmetric
Cryptography</a></dt>
<dd>The study and application of <em>Ciphers</em> that use a single secret key
projects / apache / blobdiff