IPSec VPN and smartphones

csc Posts: 2
First Comment
edited April 2021 in Security
Hi. I've a "little" problem with an ATP100 (last fw). We created a SSL VPN and it work fine. We created an IPSec VPN and it works well with a notebook and securextender. But.... The customer wants to connect to the VPN with a smartphone (android). Simple.... I can't...  I tried to recreate the IPSec with L2TP. The phone connect and disconnect. I tried to create an IKEv2 but I found some old instructions with certificate. I tried also greenbow app but it says that ikev1 is incompatible, ikev2 wont work and I don't understand how can I use the certificate. SSL VPN don't work with GB... I've no ideas now... The customer uses some other firewalls from other brands, with dedicated app and he has no problem.

I've another problem wuth another firewall and other smartphones... The customer uses the phones live internal phones. An app connct the smartphone to the internal telephone switchboard. In this case, the L2TP VPN works but.... The app can register the phone via TCP, but the call via UDP don't work. Also in this case,the manufactor of the telephone switchboard has no problem with other brands and the connected apps...
Any idea also for this?

All Replies

  • csc
    csc Posts: 2
    First Comment
    I found that for smartphone, the quicksetup was moved under "remote access vpn setup"
  • Zyxel_Can
    Zyxel_Can Posts: 342  Zyxel Employee
    Friend Collector First Answer First Comment

    @Hi csc,


    Can you share some information with us;

    Regarding to first paragraph question;

    1-   Did you configure L2TP VPN settings and connect to ATP100W with

    Regarding to second paragraph question;

    2-    Can you draw the topology with IPs on it?

    3-    Do you call the inside phone that is under ATP100W’s network or an external phone number(outside phone number)?

    4-    Can you share Configuration > ALG page configuration’s screenshot?

    5-    Where does the L2TP client connect from? Does it connect to ATP100W from outside the ATP100W’s network or inside of ATP100W’s network?


    Best regards.

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