| <?xml version="1.0" encoding="ISO-8859-1"?> |
| <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> |
| <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!-- |
| XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX |
| This file is generated from xml source: DO NOT EDIT |
| XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX |
| --> |
| <title>Glossary - Apache HTTP Server</title> |
| <link href="./style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> |
| <link href="./style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> |
| <link href="./style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /> |
| <link href="./images/favicon.ico" rel="shortcut icon" /></head> |
| <body id="manual-page" class="no-sidebar"><div id="page-header"> |
| <p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/directives.html">Directives</a> | <a href="./faq/">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p> |
| <p class="apache">Apache HTTP Server Version 2.1</p> |
| <img alt="" src="./images/feather.gif" /></div> |
| <div class="up"><a href="./"><img title="<-" alt="<-" src="./images/left.gif" /></a></div> |
| <div id="path"> |
| <a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs-project/">Documentation</a> > <a href="./">Version 2.1</a></div><div id="page-content"><div id="preamble"><h1>Glossary</h1> |
| <div class="toplang"> |
| <p><span>Available Languages: </span><a href="./en/glossary.html" title="English"> en </a> | |
| <a href="./es/glossary.html" hreflang="es" rel="alternate" title="Español"> es </a> | |
| <a href="./ko/glossary.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p> |
| </div> |
| |
| <p>This glossary defines some of the common terminology related to |
| Apache in particular, and web serving in general. More information |
| on each concept is provided in the links.</p> |
| </div> |
| <div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> |
| <div class="section"> |
| <h2><a name="definitions" id="definitions">Definitions</a></h2> |
| |
| <dl> |
| <dt><a name="authentication">Authentication</a></dt> <dd>The positive |
| identification of a network entity such as a server, a client, or a |
| user.<br /> See: <a href="howto/auth.html">Authentication, Authorization, and Access |
| Control</a></dd> |
| |
| <dt><a name="accesscontrol">Access Control</a></dt> |
| <dd>The restriction of access to network realms. In an Apache context |
| usually the restriction of access to certain <em>URLs</em>.<br /> |
| See: <a href="howto/auth.html">Authentication, Authorization, and Access |
| Control</a></dd> |
| |
| <dt><a name="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">APache eXtension Tool</a> <a name="apxs">(apxs)</a></dt> <dd>A perl script that aids in compiling <a href="#module">module</a> sources into Dynamic Shared Objects (<a href="#dso">DSO</a>s) and helps install them in the Apache Web |
| server.<br /> See: <a href="programs/apxs.html">Manual Page: apxs</a></dd> |
| |
| <dt><a name="certificate">Certificate</a></dt> |
| <dd>A data record used for authenticating network entities such |
| as a server or a client. A certificate contains X.509 information pieces |
| about its owner (called the subject) and the signing <a href="#certificationauthority">Certification Authority</a> (called the |
| issuer), plus the owner's <a href="#publickey">public key</a> and the |
| signature made by the CA. Network entities verify these signatures |
| using CA certificates.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="certificationauthority">Certification Authority</a> <a name="ca">(CA)</a></dt> <dd>A trusted third party whose purpose is to |
| sign certificates for network entities it has authenticated using |
| secure means. Other network entities can check the signature to verify |
| that a CA has authenticated the bearer of a certificate.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="certificatsigningrequest">Certificate Signing Request</a> |
| <a name="csr">(CSR)</a></dt> <dd>An unsigned <a href="#certificate">certificate</a> for submission to a <a href="#certificationauthority">Certification Authority</a>, which signs it |
| with the <a href="#privatekey">Private Key</a> of their CA |
| <em>Certificate</em>. Once the CSR is signed, it becomes a real |
| certificate.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| |
| <dt><a name="cipher">Cipher</a></dt> <dd>An algorithm or system for |
| data encryption. Examples are DES, IDEA, RC4, etc.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="ciphertext">Ciphertext</a></dt> <dd>The result after <a href="#plaintext">Plaintext</a> is passed through a <a href="#cipher">Cipher</a>.<br /> See: <a href="ssl/">SSL/TLS |
| Encryption</a></dd> |
| |
| <dt><a name="commongatewayinterface">Common Gateway Interface</a> <a name="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 /> |
| See: <a href="howto/cgi.html">Dynamic Content with CGI</a></dd> |
| |
| |
| <dt><a name="configurationdirective">Configuration Directive</a></dt> |
| <dd>See: <a href="#directive">Directive</a></dd> |
| |
| <dt><a name="configurationfile">Configuration File</a></dt> |
| <dd>A text file containing <a href="#directive">Directives</a> |
| that control the configuration of Apache.<br /> |
| See: <a href="configuring.html">Configuration Files</a></dd> |
| |
| <dt><a name="connect">CONNECT</a></dt> <dd>An HTTP <a href="#method">method</a> for proxying raw data channels over HTTP. It |
| can be used to encapsulate other protocols, such as the SSL |
| protocol.</dd> |
| |
| <dt><a name="context">Context</a></dt> <dd>An area in the <a href="#configurationfile">configuration files</a> where certain types |
| of <a href="#directive">directives</a> are allowed.<br /> See: <a href="mod/directive-dict.html#Context">Terms |
| Used to Describe Apache Directives</a></dd> |
| |
| <dt><a name="digitalsignature">Digital Signature</a></dt> |
| <dd>An encrypted text block that validates a certificate or other file. A |
| <a href="#certificationauthority">Certification Authority</a> creates a |
| signature by generating a hash of the <em>Public Key</em> embedded in a |
| <em>Certificate</em>, then encrypting the hash with its own <em>Private |
| Key</em>. Only the CA's public key can decrypt the signature, verifying |
| that the CA has authenticated the network entity that owns the |
| <em>Certificate</em>.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="directive">Directive</a></dt> <dd>A configuration command |
| that controls one or more aspects of Apache's behavior. Directives |
| are placed in the <a href="#configurationfile">Configuration |
| File</a><br /> See: <a href="mod/directives.html">Directive |
| Index</a></dd> |
| |
| <dt><a name="dynamicsharedobject">Dynamic Shared Object</a> <a name="dso">(DSO)</a></dt> <dd><a href="#module">Modules</a> compiled |
| separately from the Apache httpd binary that can be loaded on-demand.<br /> |
| See: <a href="dso.html">Dynamic Shared Object Support</a></dd> |
| |
| <dt><a name="environmentvariable">Environment Variable</a> <a name="env-variable">(env-variable)</a></dt> |
| <dd>Named variables managed by the operating system shell |
| and used to store information and communicate between programs. Apache also |
| contains internal variables that are referred to as environment variables, |
| but are stored in internal Apache structures, rather than in the |
| shell environment.<br /> |
| See: <a href="env.html">Environment Variables in Apache</a></dd> |
| |
| <dt><a name="export-crippled">Export-Crippled</a></dt> |
| <dd>Diminished in cryptographic strength (and security) in order to comply |
| with the United States' Export Administration Regulations (EAR). |
| Export-crippled cryptographic software is limited to a small key size, |
| resulting in <em>Ciphertext</em> which usually can be decrypted by brute |
| force.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="filter">Filter</a></dt> <dd>A process that is applied to |
| data that is sent or received by the server. Input filters process |
| data sent by the client to the server, while output filters process |
| documents on the server before they are sent to the client. For |
| example, the <code>INCLUDES</code> output filter processes documents |
| for <a href="#ssi">Server Side Includes</a>.<br /> See: <a href="filter.html">Filters</a></dd> |
| |
| <dt><a name="fully-qualifieddomain-name">Fully-Qualified |
| Domain-Name</a> <a name="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> |
| |
| <dt><a name="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 |
| type. Normally, all files are simply served by the server, but certain |
| file types are "handled" separately. For example, the |
| <code>cgi-script</code> handler designates files to be processed as <a href="#cgi">CGIs</a>.<br /> |
| See: <a href="handler.html">Apache's Handler Use</a></dd> |
| |
| <dt><a name="header">Header</a></dt> |
| <dd>The part of the <a href="#http">HTTP</a> request and response that |
| is sent before the actual content, and that contains meta-information |
| describing the content.</dd> |
| |
| <dt><a name=".htaccess">.htaccess</a></dt> <dd>A <a href="#configurationfile">configuration file</a> that is placed inside |
| the web tree and applies configuration <a href="#directive">directives</a> to the directory where it is placed |
| and all sub-directories. Despite its name, this file can hold almost |
| any type of directive, not just access-control directives.<br /> |
| See: <a href="configuring.html">Configuration Files</a></dd> |
| |
| <dt><a name="httpd.conf">httpd.conf</a></dt> |
| <dd>The main Apache <a href="#configurationfile">configuration file</a>. |
| The default location is <code>/usr/local/apache2/conf/httpd.conf</code>, |
| but it may be moved using run-time or compile-time configuration.<br /> |
| See: <a href="configuring.html">Configuration Files</a></dd> |
| |
| <dt><a name="hypertexttransferprotocol">HyperText Transfer |
| Protocol</a> <a name="http">(HTTP)</a></dt> <dd>The standard |
| transmission protocol used on the World Wide Web. Apache implements |
| version 1.1 of the protocol, referred to as HTTP/1.1 and defined by <a href="http://ietf.org/rfc/rfc2616.txt">RFC 2616</a>.</dd> |
| |
| <dt><a name="https">HTTPS</a></dt> |
| <dd>The HyperText Transport Protocol (Secure), the standard encrypted |
| communication mechanism on the World Wide Web. This is actually just HTTP |
| over <a name="ssl">SSL</a>.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="method">Method</a></dt> <dd>In the context of <a href="#http">HTTP</a>, 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> |
| |
| <dt><a name="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 /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="mime-type">MIME-type</a></dt> <dd>A way to describe the |
| kind of document being transmitted. Its name comes from that fact |
| that its format is borrowed from the Multipurpose Internet Mail |
| Extensions. It consists of a major type and a minor type, separated |
| by a slash. Some examples are <code>text/html</code>, |
| <code>image/gif</code>, and <code>application/octet-stream</code>. In |
| HTTP, the MIME-type is transmitted in the <code>Content-Type</code> <a href="#header">header</a>.<br /> See: <a href="mod/mod_mime.html">mod_mime</a></dd> |
| |
| <dt><a name="module">Module</a></dt> <dd>An independent part of a |
| program. Much of Apache's functionality is contained in modules that |
| you can choose to include or exclude. Modules that are compiled into |
| the Apache httpd binary are called <em>static modules</em>, while |
| modules that are stored separately and can be optionally loaded at |
| run-time are called <em>dynamic modules</em> or <a href="#dso">DSOs</a>. Modules that are included by default are called |
| <em>base modules</em>. Many modules are available for Apache that are |
| not distributed as part of the Apache HTTP Server <a href="#tarball">tarball</a>. These are referred to as <em>third-party |
| modules</em>.<br /> |
| See: <a href="mod/">Module Index</a></dd> |
| |
| <dt><a name="modulemagicnumber">Module Magic Number</a> (<a name="mmn">MMN</a>)</dt> |
| <dd> |
| Module Magic Number is a constant defined in the Apache source code |
| that is associated with binary compatibility of modules. It is changed |
| when internal Apache structures, function calls and other significant |
| parts of API change in such a way that binary compatibility cannot be |
| guaranteed any more. On MMN change, all third party modules have to be |
| at least recompiled, sometimes even slightly changed in order to work |
| with the new version of Apache. |
| </dd> |
| |
| <dt><a name="openssl">OpenSSL</a></dt> |
| <dd>The Open Source toolkit for SSL/TLS<br /> |
| see <a href="http://www.openssl.org/">http://www.openssl.org/</a></dd> |
| |
| <dt><a name="passphrase">Pass Phrase</a></dt> <dd>The word or phrase |
| that protects private key files. It prevents unauthorized users from |
| encrypting them. Usually it's just the secret encryption/decryption |
| key used for <a name="cipher">Ciphers</a>.<br /> See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="plaintext">Plaintext</a></dt> |
| <dd>The unencrypted text.</dd> |
| |
| <dt><a name="privatekey">Private Key</a></dt> <dd>The secret key in a |
| <a name="publickeycryptography">Public Key Cryptography</a> system, |
| used to decrypt incoming messages and sign outgoing ones.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="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 on to the origin |
| server, and then returns the response from the origin server to the |
| client. If several clients request the same content, the proxy |
| can deliver that content from its cache, rather than requesting it |
| from the origin server each time, thereby reducing response time.<br /> |
| See: <a href="mod/mod_proxy.html">mod_proxy</a></dd> |
| |
| <dt><a name="publickey">Public Key</a></dt> <dd>The publicly |
| available key in a <a name="publickeycryptography">Public Key |
| Cryptography</a> system, used to encrypt messages bound for its owner |
| and to decrypt signatures made by its owner.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="publickeycryptography">Public Key Cryptography</a></dt> |
| <dd>The study and application of asymmetric encryption systems, which |
| use one key for encryption and another for decryption. A corresponding |
| pair of such keys constitutes a key pair. Also called Asymmetric |
| Cryptography.<br /> See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="regularexpresion">Regular Expression</a> <a name="regex">(Regex)</a></dt> <dd>A way of |
| describing a pattern in text - for example, "all the words that begin with the |
| letter A" or "every 10-digit phone number" or even "Every sentence |
| with two commas in it, and no capital letter Q". Regular 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.</dd> |
| |
| <dt><a name="reverseproxy">Reverse Proxy</a></dt> <dd>A <a href="#proxy">proxy</a> server that appears to the client 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">Secure Sockets Layer</a> <a name="ssl">(SSL)</a></dt> <dd>A protocol created by Netscape |
| Communications Corporation for general communication authentication |
| and encryption over TCP/IP networks. The most popular usage is |
| <em>HTTPS</em>, i.e. the HyperText Transfer Protocol (HTTP) over SSL.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="serversideincludes">Server Side Includes</a> <a name="ssi">(SSI)</a></dt> <dd>A technique for embedding processing |
| directives inside HTML files.<br /> See: <a href="howto/ssi.html">Introduction to Server Side Includes</a></dd> |
| |
| <dt><a name="session">Session</a></dt> |
| <dd>The context information of a communication in general.</dd> |
| |
| <dt><a name="ssleay">SSLeay</a></dt> |
| <dd>The original SSL/TLS implementation library developed by |
| Eric A. Young</dd> |
| |
| <dt><a name="symmetriccryptophraphy">Symmetric Cryptography</a></dt> |
| <dd>The study and application of <em>Ciphers</em> that use a single secret key |
| for both encryption and decryption operations.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="tarball">Tarball</a></dt> |
| <dd>A package of files gathered together using the <code>tar</code> |
| utility. Apache distributions are stored in compressed tar archives |
| or using pkzip.</dd> |
| |
| <dt><a name="transportlayersecurity">Transport Layer Security</a> <a name="tls">(TLS)</a></dt> <dd>The successor protocol to SSL, created |
| by the Internet Engineering Task Force (IETF) for general |
| communication authentication and encryption over TCP/IP networks. TLS |
| version 1 and is nearly identical with SSL version 3.<br /> |
| See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| <dt><a name="uniformresourcelocator">Uniform Resource Locator</a> <a name="url">(URL)</a></dt> <dd>The name/address of a resource on the |
| Internet. This is the common informal term for what is formally |
| called a <a href="#uniformresourceidentifier">Uniform Resource |
| Identifier</a>. URLs are usually made up of a scheme, like |
| <code>http</code> or <code>https</code>, a hostname, and a path. A |
| URL for this page is |
| <code>http://httpd.apache.org/docs-2.1/glossary.html</code>.</dd> |
| |
| <dt><a name="uniformresourceidentifier">Uniform Resource Identifier</a> <a name="URI">(URI)</a></dt> <dd>A compact string of characters for |
| identifying an abstract or physical resource. It is formally defined |
| by <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>. |
| URIs used on the world-wide web are commonly referred to |
| as <a href="#url">URLs</a>.</dd> |
| |
| <dt><a name="virtualhosting">Virtual Hosting</a></dt> <dd>Serving |
| multiple websites using a single instance of Apache. <em>IP virtual |
| hosting</em> differentiates between websites based on their IP |
| address, while <em>name-based virtual hosting</em> uses only the name |
| of the host and can therefore host many sites on the same IP |
| address.<br /> See: <a href="vhosts/">Apache Virtual Host |
| documentation</a></dd> |
| |
| <dt><a name="x.509">X.509</a></dt> <dd>An authentication certificate |
| scheme recommended by the International Telecommunication Union |
| (ITU-T) which is used for SSL/TLS authentication.<br /> See: <a href="ssl/">SSL/TLS Encryption</a></dd> |
| |
| </dl> |
| </div></div> |
| <div class="bottomlang"> |
| <p><span>Available Languages: </span><a href="./en/glossary.html" title="English"> en </a> | |
| <a href="./es/glossary.html" hreflang="es" rel="alternate" title="Español"> es </a> | |
| <a href="./ko/glossary.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p> |
| </div><div id="footer"> |
| <p class="apache">Copyright 1999-2004 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p> |
| <p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/directives.html">Directives</a> | <a href="./faq/">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p></div> |
| </body></html> |
