Wednesday, July 9, 2008

IPv6 tunneling - IPv6IP

This is a pretty simple and straightforward manual method of tunneling IPv6 packets over an IPv4 network. IP protocol type 41 is used to tell the router that the packet inside of the IP packet is and IPv6 packet.

Here is the network:

[R1]---[R2]---[R3]---[R4]

R1-R2: IPv6 network 2002:1:0:12::/64
R2-R3: IPv4 network 172.12.23.0/24
R3-R4: IPv6 network 2002:1:0:34::/64

Make sure you enable ipv6 unicast routing on R2 and R3:

R2(config)#ipv6 unicast-routing

R3(config)#ipv6 unicast-routing


Let's create the tunnels:

R2(config)#int tunnel 0
R2(config-if)#ipv6 address 2002:1:0:23::2/64
R2(config-if)#tunnel source 172.12.23.2
R2(config-if)#tunnel destination 172.12.23.3
R2(config-if)#tunnel mode ipv6ip

R3(config)#int tun 0
R3(config-if)#ipv6 address 2002:1:0:23::3/64
R3(config-if)#tunnel source 172.12.23.3
R3(config-if)#tunnel destination 172.12.23.2
R3(config-if)#tunnel mode ipv6ip

Next we need tell the router when to use the tunnel by making some static routes. The following route tells R2 that whenever a packet comes in destined for the R3-R4 network, encapsulate it in IP and tunnel it to the tunnel destination, R3 in this case. The second route does the opposite on R3.

R2(config)#ipv6 route 2002:1:0:34::/64 tunnel 0

R3(config)#ipv6 route 2002:1:0:12::/64 tunnel 0


Let's verify:

R1#ping 2002:1:0:34::4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2002:1:0:34::4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 56/76/124 ms

5 comments:

  1. I am asking for help with configuration of manual tunnel ipv6ip in Packet Tracer 5.2. I cannot configure a command for interface tunnel 0 IPv6 address in the router 2811. It does not recognize the command at all even if ipv6 unicast-routing is turned on.

    Router(config)#int tunnel 0

    %LINK-5-CHANGED: Interface Tunnel0, changed state to up
    Router(config-if)#ipv6 add
    Router(config-if)#ipv6 adddress 2002:1:0:23::2/64
    ^
    % Invalid input detected at '^' marker.

    ReplyDelete
  2. You're not doing anything wrong in Packet Tracer. As of PT v5.3.1.0044 the capability to create a tunnel interface with IPv6 addressing still does NOT exist.

    ReplyDelete
  3. I am having problem with this command line, I am using cisco 2811 in packet tracer. Please help. R2(config-if)#tunnel mode ipv6ip

    ReplyDelete
  4. PT v5.3 does not support IPv6 tunnels, you can use emulator GNS3 v0.7.2 to experiment IPv6 tunnels.

    ReplyDelete

Note: Only a member of this blog may post a comment.