Add a subsection to Routing to mention Multicast routing, largely

to cross-reference mrouted(8) and mention options MROUTING.

Sponsored by:	Network Associates Laboratories

en_US.ISO8859-1/books/handbook/advanced-networking/chapter.sgml

@@ -482,6 +482,27 @@ host2.example.com link#1             UC          0        0
       <para>For more information, see the manual page for
 	  &man.traceroute.8;.</para>
     </sect2>
+
+    <sect2>
+      <title>Multicast Routing</title>
+      <indexterm>
+	<primary>multicast</primary>
+	<secondary>options MROUTING</secondary>
+      </indexterm>
+      <para>FreeBSD supports both multicast applications and multicast
+	routing natively.  Multicast applications do not require any
+	special configuration of FreeBSD; applications will generally
+	run out of the box.  Multicast routing requires configuration
+	requires that support be compiled into the kernel:</para>
+
+      <programlisting>options MROUTING</programlisting>
+
+      <para>In addition, the multicast routing daemon, &man.mrouted.8;
+	must be configured to set up tunnels and DVMRP via
+	<filename>/etc/mrouted.conf</filename>.  More details on
+	multicast configuratoin may be found in the man pages for
+	mrouted.</para>
+    </sect2>
   </sect1>
 
   <sect1 id="network-wireless">