DTMF, Yealink T38g and NTE-101

[Mullenlaw]

I have a bunch of T38 phones and for the most part the DTMF works.

But there are a few situations where the other side says "invalid".

I've messed with all the setting options / combinations.

What should it be set to?

Our provider says we should be using NTE-101 inband.

I assume that is Inband with a payload of 101, but not sure what the NTE means
and what the selection for "How to INFO DTMF" should be for yealink.

:?:

 

[danhriscanu]

Hi,

NTE stands for Named Telephone Events and is documented in RFC 2833, so if your provider specified NTE with 101 payload you should use RFC 2833 not inband. So choose DTMF types RFC2833 and How to INFO DTMS choose DTMF-Relay to enable NTE mechanism. If you want to read more about DTMF and NTE mechanism look here: http://www.ietf.org/rfc/rfc2833.txt