+alias tap0 ethertap
+options tap0 -o tap0 unit=0
+alias tap1 ethertap
+options tap1 -o tap1 unit=1
+@end example
+
+Add more alias/options lines if necessary.
+
+For kernels 2.4.0 and higher:
+
+@example
+Code maturity level options
+[*] Prompt for development and/or incomplete code/drivers
+Network device support
+<M> Universal TUN/TAP device driver support
+@end example
+
+It's not necessary to compile this driver as a module, even if you are going to
+run more than one instance of tinc.
+
+If you have an early 2.4 kernel, you can choose both the TUN/TAP driver and the
+`Ethertap network tap' device. This latter is marked obsolete, and chances are
+that it won't even function correctly anymore. Make sure you select the
+universal TUN/TAP driver.
+
+If you decide to build the TUN/TAP driver as a kernel module, add these lines
+to @file{/etc/modules.conf}:
+
+@example
+alias char-major-10-200 tun
+@end example
+
+
+@c ==================================================================
+@node Configuration of the FreeBSD kernel, Configuration of the Solaris kernel, Configuration of the Linux kernel, Configuring the kernel
+@subsection Configuring the FreeBSD kernel
+
+This section will contain information on how to configure your FreeBSD
+kernel to support the universal TUN/TAP device. For 5.0 and 4.1
+systems, this is included in the kernel configuration, for earlier
+systems (4.0 and 3.x), you need to install the universal TUN/TAP driver
+yourself.
+
+Unfortunately somebody still has to write the text.
+
+
+@c ==================================================================
+@node Configuration of the Solaris kernel, , Configuration of the FreeBSD kernel, Configuring the kernel
+@subsection Configuring the Solaris kernel
+
+This section will contain information on how to configure your Solaris
+kernel to support the universal TUN/TAP device. You need to install
+this driver yourself.
+
+Unfortunately somebody still has to write the text.
+
+
+@c ==================================================================
+@node Libraries, , Configuring the kernel, Installing tinc - preparations
+@section Libraries
+
+@cindex requirements
+Before you can configure or build tinc, you need to have the OpenSSL
+library installed on your system. If you try to configure tinc without
+having installed it, configure will give you an error message, and stop.
+
+@menu
+* OpenSSL::
+@end menu
+
+
+@c ==================================================================
+@node OpenSSL, , Libraries, Libraries
+@subsection OpenSSL
+
+@cindex OpenSSL
+For all cryptography-related functions, tinc uses the functions provided
+by the OpenSSL library.
+
+If this library is not installed, you wil get an error when configuring
+tinc for build. Support for running tinc without having OpenSSL
+installed @emph{may} be added in the future.
+
+You can use your operating system's package manager to install this if
+available. Make sure you install the development AND runtime versions
+of this package.
+
+If you have to install OpenSSL manually, you can get the source code
+from @url{http://www.openssl.org/}. Instructions on how to configure,
+build and install this package are included within the package. Please
+make sure you build development and runtime libraries (which is the
+default).
+
+If you installed the OpenSSL libraries from source, it may be necessary
+to let configure know where they are, by passing configure one of the
+--with-openssl-* parameters.
+
+@example
+--with-openssl=DIR OpenSSL library and headers prefix
+--with-openssl-include=DIR OpenSSL headers directory
+ (Default is OPENSSL_DIR/include)
+--with-openssl-lib=DIR OpenSSL library directory
+ (Default is OPENSSL_DIR/lib)