Will the SPA2102-NA Voice Gateway support inbound DTMF?

[hardwareshopper]

I'm considering the SPA2102-NA Voice Gateway to replace my Ooma Telo (and subscribe to a new VOIP provider also) after getting burned by the fact that the Ooma Telo and/or Ooma VOIP service will not support inbound DTMF. Because of this deficiency, I am unable to control my alarm system and answering machine remotely. Can anyone advise if the SPA2102-NA Voice Gateway will properly support inbound DTMF? I am unable to find the answer in the documentation I have read.

[oldhard47]

[Sorry, don't know much about this topic but happed to have a SPA-2102.]

I have an old-ish Linksys ATA Administrator Guide Document Version 3.2 that covers the SPA-2102 amongst others. I'll put some "DTMF" snippets below.

"In-Band and Out-of-Band (RFC 2833) (SIP INFO *) The Linksys ATA may relay DTMF digits as out-of-band events to preserve the fidelity of the digits. This can enhance the reliability of DTMF transmission required by many IVR applications such as dial-up banking and airline information."

"DTMF Relay MIME Type" "MIME Type used in a SIP INFO message to signal a DTMF event.

The default is application/dtmf-relay."

"DTMF Process INFO" "(Not in PAP2T) To use the DTMF process info feature, select yes. Otherwise, select no.

The default is yes."

"DTMF Tx Method" "Select the method to transmit DTMF signals to the far end: InBand, AVT, INFO, Auto, InBand+INFO, or AVT+INFO. InBand sends DTMF using the audio path. AVT sends DTMF as AVT events. INFO uses the SIP INFO method. Auto uses InBand or AVT based on the outcome of codec negotiation.

The default is Auto."

[hardwareshopper]

Thanks for your response John. I'm not sure that those snippets do not refer to outbound DTMF. References to "transmit DTMF signals to the far end" and "applications such as dial-up banking and airline information" seem to be pertaining to outbound DTMF, which my Ooma deals with successfully, it is just the inbound tones that are not supported.

[Daniele Giordano]

In band DTMF works only if the vocal codec is set to G711. Other compressed codecs like G729 destroy DTMF tones.
What codecs are configured on your SPA?

Regards.

[hardwareshopper]

Daniele,

I do not have a SPA2102 yet, I'm considering purchasing one to replace the Ooma I have which will not support inbound DTMF. To reiterate, are you saying that the SPA1202 will support inbound DTMF if codec G711 is utilized? Thanks in advance.

[Daniele Giordano]

If you set in band DTMF with G711 codec, the SPA2102 will transport transparently DTMF tones to device connected to it. We use SPA2102 with ContactID devices. ContactID is a protocol that uses fast DTMF sequences.

Regards.

[hardwareshopper]

Excellent. Thank you for your time !