> I have a nanobts unit 139 with a software that somehow only accepts GSM FR
> (and not EFR), unless I also send the RTP payload type IE (
> RSL_IE_IPAC_RTP_PAYLOAD ) in the CRCX and MDCX messages. (and only the "RTP
> payload type" IE, the "RTP payload type 2" has no effect I can see).

thanks for pointing this out. Now the question is, would that affect the later
models? Do you have any later models to test? If later models / versions
don't mind the RTP Payload (non-type-2), we can jusy simply always use that.

I tested with a later version othe 139 software and including the RTP payload type IE works fine. I don't have any other units (EDGE ones) so I can't test. But I just posted the patch so someone could test ...

> For GSM FR the RFC specifies PT=3 but for HR/EFR/AMR, they are dynamic and
> must be chosed in the 96-127 range.
> AFAIK, we could just use a static mapping in openbsc or load that from the
> config. Does anyone sees a downside to that ?

static mapping is fine with me, patches welcome.

Patch sent on the ML.

Sylvain