[chiusa] Pinging network interface created by a simulator

Good Morning, I'm using a wsn simulator (openWSN) in which nodes can communicate using a "tun0" interface. I'm using ubuntu 16.04.

My goal is pinging the DAG root, once of these nodes, from an other pc that is in an other network. The DAG root has a IPv6 address bbbb::1415:92cc:0:1 and nodes communicate using the tun0. I'm thinking to procede in this way:

1) ping the tun0 interface

2) redirect data that arrive at tun0 to the DAG root

Is this the right approach? Trying to approach to (1) I've realized that is not possible ping the tun0 because hasn't a global IPv6. I suppose that a static IP is needed, but how to do?

Here some network informations:

"route -n" shows:

    Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.151.0.1      0.0.0.0         UG    0      0        0 eth0
10.91.0.0       0.0.0.0         255.255.0.0     U     9      0        0 wlan0
10.151.0.0      0.0.0.0         255.255.0.0     U     1      0        0 eth0

"ip a" shows:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 14:58:d0:c8:20:03 brd ff:ff:ff:ff:ff:ff
    inet 10.151.1.22/16 brd 10.151.255.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::1658:d0ff:fec8:2003/64 scope link 
       valid_lft forever preferred_lft forever
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 9c:ad:97:9d:fd:0d brd ff:ff:ff:ff:ff:ff
    inet 10.91.3.113/16 brd 10.91.255.255 scope global wlan0
       valid_lft forever preferred_lft forever
    inet6 fe80::9ead:97ff:fe9d:fd0d/64 scope link 
       valid_lft forever preferred_lft forever
7: tun0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 500
    link/none 
    inet6 bbbb::1/64 scope global 
       valid_lft forever preferred_lft forever
    inet6 fe80::1/64 scope link 
       valid_lft forever preferred_lft forever

Can someone help me? thank you