<?xml version="1.0" encoding="utf-8"?>
<page xmlns="http://projectmallard.org/1.0/" type="topic" style="task" id="net-firewall-on-off" xml:lang="nl">

  <info>
    <link type="guide" xref="net-security"/>
    <desc>You can control which programs can access the network. This helps to keep your computer secure.</desc>
    <revision pkgversion="3.2" date="2011-09-26" status="final"/>
    <credit type="author">
      <name>Paul W. Frields</name>
      <email>stickster@gmail.com</email>
    </credit>

    <include xmlns="http://www.w3.org/2001/XInclude" href="legal.xml"/>
  </info>

  <title>Enable or block firewall access</title>

<comment>
<cite date="2011-09-26">shaunm</cite>
<p>Continue to revisit this page until we can provide real instructions.
As it is, we're stuck in "whatever distros do" territory.</p>
</comment>

  <p>Your system should be equipped with a <em>firewall</em> that allows it to block programs from being accessed by other people on the internet or your network. This helps to keep your computer secure.</p>
  <p>Many applications can provide network services. For instance, you can share files or let someone view your desktop remotely. Depending on how your computer is set up, you may need to adjust the firewall to allow these services to work as intended.</p>
  <p>Each program that provides network services uses a specific <em>network port</em>. To enable other computers on the network to access a service, you may need to "open" its assigned port on the firewall:</p>

  <steps>
    <item>
      <p>Go to <gui>Activities</gui> in the top left corner of the screen and start your firewall application. You may need to install a firewall manager yourself if you can't find one (for example, Firestarter or GUFW).</p>
    </item>
    <item>
      <p>Open or disable the port for your network service, depending on whether you want people to be able to access it or not. Which port you need to change will <link xref="net-firewall-ports">depend on the service</link>.</p>
    </item>
    <item>
      <p>Save or apply the changes, following any additional instructions given by the firewall tool.</p>
    </item>
  </steps>

</page>
