.TH 6IN4 8
.SH NAME
-6in4 - configure and run automatic or manual 6to4 tunnel of IPv6 through IPv4
+6in4, ayiya - configure and run automatic or manual tunnel of IPv6 through IPv4
.SH SYNOPSIS
.B ip/6in4
[
.B -ag
] [
+.B -m
+.I mtu
+] [
.B -x
.I netmtpt
] [
-.IB local6[ / mask]
+.B -o
+.I outnetmtpt
+] [
+.B -i
+.I local4
+] [
+.IB local6 [ /mask ]
[
.I remote4
[
.I remote6
] ] ]
+.br
+.B ip/ayiya
+[
+.B -g
+] [
+.B -m
+.I mtu
+] [
+.B -x
+.I netmtpt
+] [
+.B -k
+.I secret
+]
+.IB local6 [ /mask ]
+.I remote4
+.I remote6
.SH DESCRIPTION
.I 6in4
-sets up and maintains a tunnel of IPv6 traffic through an IPv4 connection.
+sets up and maintains a 6to4 tunnel of IPv6 traffic through an IPv4 connection.
+.I Ayiya
+is similar, but uses the UDP based Anything In Anything protocol to
+tunnel IPv6 traffic.
.PP
.I Local6
and
defaults to a link-local address constructed from
.IR remote4 ).
.PP
-.I 6in4
-forks a pair of background processes to copy packets to and from
+The program forks a pair of background processes to copy packets to and from
the tunnel.
.PP
Options are:
.PD 0
.TP
.B -a
+for
+.IR 6in4 ,
permit any remote IPv4 address as the far end of a tunnel.
This is likely to be useful for the server side of a tunnel.
.TP
+.B -i
+for
+.IR 6in4 ,
+define what is the local IPv4 address, otherwise it takes the first
+non-loopback address of the outside IP stack.
+.TP
.B -g
use the tunnel as the default route for global IPv6 addresses
.TP
+.B -m
+.I mtu
+specifies the outside MTU in bytes from which the inside
+tunnel MTU is derived. Deaults to 1500 - 8 (Ethernet - PPPoE).
+.TP
.B -x
use the network mounted at
.I netmtpt
instead of
-.LR /net .
+.LR /net
+for binding the tunnel interface and sending/receiving IPv4
+packets.
+.TP
+.B -o
+for
+.IR 6in4 ,
+use
+.I outnetmtpt
+for the IPv4 packets but bind the IPv6 interface on
+.LR /net
+or
+.I netmtpt
+when specified by a previous
+.B -x
+option.
+.TP
+.B -k
+for
+.IR ayiya ,
+use the shared secret key
+.I secret
+to authenticate messages on the tunnel.
.PD
.SH EXAMPLES
If your primary IPv4 address is public,
.B /lib/rfc/rfc3056
.br
.B /lib/rfc/rfc3068
+.br
+.B http://tools.ietf.org/id/draft-massar-v6ops-ayiya-02.txt
.SH BUGS
Needs a kernel with an
.I ipmux