[AusNOG] Optus VoWiFi failing over Starlink Business - seeking Optus contact

[Cameron de Witte]

Hi all,

Hoping someone on the list might be able to point me toward a technical contact within Optus who could assist with a Voice over WiFi issue.

We operate Starlink Business services at a remote site where there is limited terrestrial mobile coverage, making VoWiFi essential for our team. We're finding that Optus VoWiFi will not activate over the Starlink Business connection since the recent outages and subsequent IP reallocation, testing has it working fine on other ISPs and connections.

What we've established so far:
- The Starlink Business panels use a public IP allocation. VoWiFi does not activate on any handset we've tested.
- Consumer Starlink panels on the same site (which sit behind CGNAT on a different public IP range) work without issue - VoWiFi activates and calls complete normally.
- We've tested across multiple handsets with the same result.
- Packet captures show outgoing connection requests leaving the site, but we only see single packets returning from the Optus side - the session seem to never establish.
- As a workaround, routing the traffic back to our head office via VPN and out through that connection allows VoWiFi to work, but this isn't a sustainable solution for the site.

The behaviour appears to be something on the Optus side is filtering traffic for the Starlink Business IP range, while the consumer range is fine.

If anyone has a technical or network engineering contact at Optus who might be able to look into this, I'd really appreciate an introduction. Happy to provide packet captures or any other detail that would help.

Thanks in advance,
Cameron.


Cameron de Witte
Project Network Engineer        [cid:currentemailgif_85c8de77-bf36-4db7-ac77-3ca66b53690e.gif]
P: 1300 766 720<tel:1300%20766%20720>
E: camerondw at smileit.com.au<mailto:camerondw at smileit.com.au>
Level 1D, Tingalpa Industrial Estate, 60 Enterprise Place, Tingalpa, QLD 4173



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