+@item -netdev l2tpv3,id=@var{id},src=@var{srcaddr},dst=@var{dstaddr}[,srcport=@var{srcport}][,dstport=@var{dstport}],txsession=@var{txsession}[,rxsession=@var{rxsession}][,ipv6][,udp][,cookie64][,counter][,pincounter][,txcookie=@var{txcookie}][,rxcookie=@var{rxcookie}][,offset=@var{offset}]
+@item -net l2tpv3[,vlan=@var{n}][,name=@var{name}],src=@var{srcaddr},dst=@var{dstaddr}[,srcport=@var{srcport}][,dstport=@var{dstport}],txsession=@var{txsession}[,rxsession=@var{rxsession}][,ipv6][,udp][,cookie64][,counter][,pincounter][,txcookie=@var{txcookie}][,rxcookie=@var{rxcookie}][,offset=@var{offset}]
+Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
+protocol to transport Ethernet (and other Layer 2) data frames between
+two systems. It is present in routers, firewalls and the Linux kernel
+(from version 3.3 onwards).
+
+This transport allows a VM to communicate to another VM, router or firewall directly.
+
+@item src=@var{srcaddr}
+ source address (mandatory)
+@item dst=@var{dstaddr}
+ destination address (mandatory)
+@item udp
+ select udp encapsulation (default is ip).
+@item srcport=@var{srcport}
+ source udp port.
+@item dstport=@var{dstport}
+ destination udp port.
+@item ipv6
+ force v6, otherwise defaults to v4.
+@item rxcookie=@var{rxcookie}
+@item txcookie=@var{txcookie}
+ Cookies are a weak form of security in the l2tpv3 specification.
+Their function is mostly to prevent misconfiguration. By default they are 32
+bit.
+@item cookie64
+ Set cookie size to 64 bit instead of the default 32
+@item counter=off
+ Force a 'cut-down' L2TPv3 with no counter as in
+draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
+@item pincounter=on
+ Work around broken counter handling in peer. This may also help on
+networks which have packet reorder.
+@item offset=@var{offset}
+ Add an extra offset between header and data
+
+For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
+on the remote Linux host 1.2.3.4:
+@example
+# Setup tunnel on linux host using raw ip as encapsulation
+# on 1.2.3.4
+ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
+ encap udp udp_sport 16384 udp_dport 16384
+ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
+ 0xFFFFFFFF peer_session_id 0xFFFFFFFF
+ifconfig vmtunnel0 mtu 1500
+ifconfig vmtunnel0 up
+brctl addif br-lan vmtunnel0
+
+
+# on 4.3.2.1
+# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
+
+qemu-system-i386 linux.img -net nic -net l2tpv3,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter
+
+
+@end example
+