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    <title>Apache Keep-Alive Support</title>
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      <h3>Apache HTTP Server</h3>
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    <h1 align="CENTER">Apache Keep-Alive Support</h1>
    <hr />

    <h2>What is Keep-Alive?</h2>
    The Keep-Alive extension to HTTP, as defined by the
    <code>HTTP/1.1</code> draft, allows persistent connections.
    These long-lived HTTP sessions allow multiple requests to be
    send over the same TCP connection, and in some cases have been
    shown to result in an almost 50% speedup in latency times for
    HTML documents with lots of images. 

    <h2>Enabling Keep-Alive Support</h2>
    Apache 1.1 comes with Keep-Alive support on by default, however
    there are some directives you can use to modify Apache's
    behavior: 

    <p><strong>Note</strong>: Apache 1.2 uses a different syntax
    for the <a href="mod/core.html#keepalive">KeepAlive</a>
    directive.</p>

    <h3>KeepAlive</h3>
    <a href="mod/directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> KeepAlive
    <em>max-requests</em><br />
     <a href="mod/directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>KeepAlive
    5</code><br />
     <a href="mod/directive-dict.html#Context"
    rel="Help"><strong>Context:</strong></a> server config<br />
     <a href="mod/directive-dict.html#Status"
    rel="Help"><strong>Status:</strong></a> Core 

    <p>This directive enables Keep-Alive support. Set
    <em>max-requests</em> to the maximum number of requests you
    want Apache to entertain per connection. A limit is imposed to
    prevent a client from hogging your server resources. Set this
    to <code>0</code> to disable support.</p>

    <h3>KeepAliveTimeout</h3>
    <a href="mod/directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> KeepAliveTimeout
    <em>seconds</em><br />
     <a href="mod/directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> <code>KeepAliveTimeout
    15</code><br />
     <a href="mod/directive-dict.html#Context"
    rel="Help"><strong>Context:</strong></a> server config<br />
     <a href="mod/directive-dict.html#Status"
    rel="Help"><strong>Status:</strong></a> Core 

    <p>The number of seconds Apache will wait for a subsequent
    request before closing the connection. Once a request has been
    received, the timeout value specified by the <a
    href="mod/core.html#timeout"><code>Timeout</code></a> directive
    applies.</p>

    <h2>When Keep-Alive Is Used</h2>
    In order for Keep-Alive support to be used, first the browser
    must support it. Many current browsers, including Netscape
    Navigator 2.0, and Spyglass Mosaic-based browsers (including
    Microsoft Internet Explorer) do. Note, however, that some
    Windows 95-based browsers misbehave with Keep-Alive-supporting
    servers; they may occasionally hang on a connect. This has been
    observed with several Windows browsers, and occurs when
    connecting to any Keep-Alive server, not just Apache. Netscape
    3.0b5 and later versions are known to work around this problem.
    

    <p>However, Keep-Alive support only is active with files where
    the length is known beforehand. This means that most CGI
    scripts, server-side included files and directory listings will
    not use the Keep-Alive protocol. While this should be
    completely transparent to the end user, it is something the
    web-master may want to keep in mind.</p>
        <hr />

    <h3 align="CENTER">Apache HTTP Server</h3>
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