<HTML ><HEAD ><TITLE >GRE and other tunnels</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK REL="HOME" TITLE="Linux Advanced Routing & Traffic Control HOWTO" HREF="index.html"><LINK REL="PREVIOUS" TITLE="Routing for multiple uplinks/providers" HREF="lartc.rpdb.multiple-links.html"><LINK REL="NEXT" TITLE="A few general remarks about tunnels:" HREF="lartc.tunnel.remarks.html"></HEAD ><BODY CLASS="CHAPTER" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >Linux Advanced Routing & Traffic Control HOWTO</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="lartc.rpdb.multiple-links.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="lartc.tunnel.remarks.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><H1 ><A NAME="LARTC.TUNNEL" ></A >Chapter 5. GRE and other tunnels</H1 ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT >5.1. <A HREF="lartc.tunnel.remarks.html" >A few general remarks about tunnels:</A ></DT ><DT >5.2. <A HREF="lartc.tunnel.ip-ip.html" >IP in IP tunneling</A ></DT ><DT >5.3. <A HREF="lartc.tunnel.gre.html" >GRE tunneling</A ></DT ><DD ><DL ><DT >5.3.1. <A HREF="lartc.tunnel.gre.html#AEN324" >IPv4 Tunneling</A ></DT ><DT >5.3.2. <A HREF="lartc.tunnel.gre.html#AEN342" >IPv6 Tunneling</A ></DT ></DL ></DD ><DT >5.4. <A HREF="lartc.tunnel.userland.html" >Userland tunnels</A ></DT ></DL ></DIV ><P >There are 3 kinds of tunnels in Linux. There's IP in IP tunneling, GRE tunneling and tunnels that live outside the kernel (like, for example PPTP). </P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="lartc.rpdb.multiple-links.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="lartc.tunnel.remarks.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Routing for multiple uplinks/providers</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" > </TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >A few general remarks about tunnels:</TD ></TR ></TABLE ></DIV ></BODY ></HTML >