[throw0101d]

> T.38 is an ITU recommendation for allowing transmission of fax over IP networks (FoIP) in real time.

* https://en.wikipedia.org/wiki/T.38

* https://www.itu.int/rec/T-REC-T.38/en

[yokem55]

T.38 can help - but the codec reinvite process to switch to it when you detect fax tones can trip up a lot of machines .. And you still have to transcode the t38 back to 711 or tdm to send the call upstream which can be problematic as well on some switches.