The IP address 172.31.9.106 you shared for media/signaling. This address falls within a private IP range (RFC 1918) and is not publicly routable nor announced by any ASN. According to my understanding, If we enable UDP ports 10000–60000 to/from the same IPs, it should work as Vapi doesn't use a fixed RTP IP range. However, we can’t accept 172.31.9.106, it’s a private IP and not routable. Could you kindly provide a public-facing IP for interoperability or confirm whether its okay not to whitelist 172.31.9.106?

You only need to whitelist the following public IPs for Vapi SIP trunk interoperability: -

44.229.228.186/32

-

44.238.177.138/32

The IP

172.31.9.106

is a private address and does not need to be whitelisted, as it is not publicly routable or required for external SIP signaling/media. You can safely omit it from your firewall configuration. [Reference: Vapi SIP Trunking Documentation](https://docs.vapi.ai/advanced/sip/sip-trunk#network-requirements) Source: - [Vapi SIP Trunking Documentation](https://docs.vapi.ai/advanced/sip/sip-trunk#network-requirements)

Are you sure @User ?

The IP 172.31.9.106 is private and not routable, so you should whitelist vapi’s public SIP/media IPs 44.229.228.186 and 44.238.177.138 and enable UDP ports 10000–60000 for proper interoperability..