Need help understanding an SBC.

[YWiegman]

Good morning guys,

Recently I've done some testing in regards to the usage of SBCs.
All of our 3CX instances are hosted in a private cloud, so when we're installing new hardware (gigaset DECT or Yealink IP Phones) we're using an SBC installed on a local Raspberry Pi to provision the devices.
Recently some of our customers wanted to migrate to 3CX (from our previous platform) and they are using some older hardware (Mitel/Aastra devices).
When I try to manually link them to the PBX this doesn't work when I install a SBC in the network and set that internal IP address as the registar server, it does work.

Can somebody please explain me if this is a viable way of working with the older phones?

Thanks in advance!

 

[JohnS_3CX]

Hi @YWiegman

For the few Aastra (or Mitel after the merger) models that are supported, it's only in LAN mode support - definitely not SBC or STUN.

They are EOL products so they are not maintained or tested to work for modern 3CX versions like V18, and they lack the support to even provision outside of LAN mode. See the limitations:
https://www.3cx.com/sip-phones/aastra/#h.kbw9qhyp1sm2

The current modern devices that are supported, use the FQDN as their registrar, and the SBC IP as their proxy. In theory you could make any SIP device work if they support this provisioning, but in practice your mileage may vary.

The best solution is to replace the older devices with something newer from our currently supported models.
https://www.3cx.com/sip-phones/

This will ensure that they will be able to provision, and work with the SBC as tested and confirmed by both us and the manufacturer. We also offer various apps that can in many (but not all) cases replace desk phones altogether.

If you still want to use the Aastra devices in a supported manner, I think your only solution would be to setup a transparent VPN between the site and the cloud PBX. This is also extra work and complexity that can be avoided when using supported devices or the apps.

Hope this is at least somewhat useful regarding your questions!