> but I am checking my sngrep and there are no sip traffic coming back from Microsoft.
sngrep won't show anything, the traffic to/from MS is encrypted. You'll need to install and configure something like SIPDUMP or HEP.
I'm afraid this isn't the easiest of tasks for someone who seems to be just getting started with VoIP. Too many things to consider in this task.
Run the below to check if MS replies back. Besides that, I did what I could to help over email. Good luck!
sipexer -options -contact-uri "sip:abcsbc.com:5061;transport=tls" -fd "
abcsbc.com" -td "
sip.pstnhub.microsoft.com;transport=tls" \
-tls-certificate "/usr/local/etc/kamailio/bundle.crt" -tls-key "/usr/local/etc/kamailio/privkey.pem" \
-xh "Max-Forwards: 70" -ua "Ribbon-SIPGateway" "sip:sip.pstnhub.microsoft.com:5061;transport=tls"
Note: adjust certs path and FQDN, if needed.
Regards,
Sergiu
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