<?xml version="1.0"?>

<!--
  Copyright (C) Nginx, Inc.
  -->

<!DOCTYPE module SYSTEM "../../../../dtd/module.dtd">

<module name="Module ngx_http_spdy_module"
        link="/en/docs/http/ngx_http_spdy_module.html"
        lang="en"
        rev="3">

<section id="summary">

<para>
The <literal>ngx_http_spdy_module</literal> module provides experimental
support for <link url="http://www.chromium.org/spdy/spdy-protocol">SPDY</link>.
Currently,
<link url="http://www.chromium.org/spdy/spdy-protocol/spdy-protocol-draft2">draft
2</link> of SPDY protocol is implemented.
</para>

<para>
This module is not built by default, it should be enabled with
the <literal>--with-http_spdy_module</literal>
configuration parameter.
</para>

</section>


<section id="bugs" name="Known Bugs">

<para>
The module is experimental, caveat emptor applies.
</para>

<para>
Current implementation of SPDY protocol does not support “server push”.
</para>

<para>
In versions prior to 1.5.9, responses in SPDY connections could not be
<link doc="ngx_http_core_module.xml" id="limit_rate">rate limited</link>.
</para>

</section>


<section id="example" name="Example Configuration">

<para>
<example>
server {
    listen 443 ssl spdy;

    ssl_certificate server.crt;
    ssl_certificate_key server.key;
    ...
}
</example>
<note>
Note that in order to accept both
<link doc="ngx_http_ssl_module.xml">HTTPS</link> and SPDY connections
simultaneously on the same port,
<link url="http://www.openssl.org">OpenSSL</link> library used should support
“Next Protocol Negotiation” TLS extension, available since OpenSSL
version 1.0.1.
</note>
</para>

</section>


<section id="directives" name="Directives">

<directive name="spdy_headers_comp">
<syntax><value>level</value></syntax>
<default>0</default>
<context>http</context>
<context>server</context>

<para>
Sets the header compression <value>level</value> of a response in a range from
1 (fastest, less compression) to 9 (slowest, best compression).
The special value 0 turns off the header compression.
</para>

</directive>

</section>


<section id="variables" name="Embedded Variables">

<para>
The <literal>ngx_http_spdy_module</literal> module
supports the following embedded variables:
<list type="tag" compact="no">

<tag-name id="var_spdy"><var>$spdy</var></tag-name>
<tag-desc>
SPDY protocol version for SPDY connections,
or an empty string otherwise;
</tag-desc>

<tag-name id="var_spdy_request_priority"><var>$spdy_request_priority</var>
</tag-name>
<tag-desc>
request priority for SPDY connections,
or an empty string otherwise.
</tag-desc>

</list>
</para>

</section>

</module>