ZyXEL Communications VPN Series Handbook page 209

www.zyxel.com
To test whether a tunnel is working, ping from a computer at one site to a
computer at the other. Ensure that both computers have Internet access (via the
IPSec devices).
PC behind ZyWALL/USG > Window 7 > cmd > ping 192.168.75.33
PC behind Cisco> Window 7 > cmd > ping 192.168.1.33
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