Zyxel LTE5398-M904 and STUN server

BruCom

Hello community

is there any of you that knows if the above modem can use a STUN server ?

I had a look to the user manual and found nothing but I'm not an expert and could this feature goes under another name.

In addition, in the configuration back up file, I saw there are parameters to connect to a STUN server but the WEB interface does not show any. Could it be that such parameters are enabled only when a specific option is selected or are applicable ony to other models other then the LTE5398-M904 ?

Thank you

tonygibbs16

Hi @BruCom

Session Traversal Utilities for NAT (STUN) is designed so that VoIP will work through firewalls and with private IP addresses and NAT.

https://www.3cx.com/pbx/what-is-a-stun-server/#:~:text=A%20STUN%20(Session%20Traversal%20of,outside%20of%20the%20local%20network. has some information for example.

I have used STUN through another Zyxel device in my home set-up in order to get VoIP working, because my phone is on a private IP address inside my local area network.

If your VoIP provider runs a STUN server, then it will likely work though LTE5398-m904 as long as your 4G provider will also pass it through.

I downloaded the user guide for LTE5398-M904 from Zyxel's Swiss distributor at https://www.studerus.ch/de/support/downloadcenter/ by searching for it, and it mentions a set-up of an outbound proxy being possible so that you don't have to use STUN or SIP ALG, see below.

I hope that this helps.

Kind regards,

Tony

Friday

Hi @BruCom,

May I understand your usage of STUN server? Any specific service you would like to achieve?

thank you!

BruCom

Hi @Friday

STUN server usage was suggested by my VoIP provider to fix disconnections probably due to the fact my 4G provider does not provide a public IP address.

tonygibbs16

Hi @BruCom

Session Traversal Utilities for NAT (STUN) is designed so that VoIP will work through firewalls and with private IP addresses and NAT.

https://www.3cx.com/pbx/what-is-a-stun-server/#:~:text=A%20STUN%20(Session%20Traversal%20of,outside%20of%20the%20local%20network. has some information for example.

I have used STUN through another Zyxel device in my home set-up in order to get VoIP working, because my phone is on a private IP address inside my local area network.

If your VoIP provider runs a STUN server, then it will likely work though LTE5398-m904 as long as your 4G provider will also pass it through.

I downloaded the user guide for LTE5398-M904 from Zyxel's Swiss distributor at https://www.studerus.ch/de/support/downloadcenter/ by searching for it, and it mentions a set-up of an outbound proxy being possible so that you don't have to use STUN or SIP ALG, see below.

I hope that this helps.

Kind regards,

Tony

BruCom

Hi @tonygibbs16

Thank you very much for your reply.
I think that my VoIP provider runs a STUN server since, back in March, he provided me the parameters to connect my device to the server together to other suggestions to keep a stable SIP connection.
Another suggestion from the VoIP provider was to turn on the "keep alive" function.

I went thru the device manual and did not find a way to connect to a STUN server or a "keep alive" function.
This is the reason why I opened this tread asking support to the community.

Anyway, me too I found that page in the user manual and I turned of the SIP ALG, changed the "SIP Register Expiration Duration" to 120 seconds and the "SIP Register Fail Re-try Timer" to 900 seconds.
This from some time and I must say that the SIP registration is a lot much stable now.
So, yes, seems that it works though LTE5398-M904 and 4G provider also pass it through.

Thank you again for you explanation and support.