Transcoding

[AndrzejP]

Hi,

assuming I have 1+1 ProSBC and TSBC-HW-TRANS-1372.

0. If a call has negotiated RFC2833 dtmf and I receive inband DTMF can ProSBC with hardware transcoding unit transcode it to RFC2833? I've got SIP trunks where carriers negotiate RFC2833 but sometimes deliver DTMF in inband and need to resolve this

1. Can I enable transcoding for single NAP and not others?
2. Can I enable transcoding only for calls in one direction on NAP? I need to process only inbound calls with inband DTMF to RFC dtmf. I don not need transcoding on outbound calls.
3. Can I enable transcoding only for one direction of audio to conserve resources for more calls? (inband DTMF to RFC dtmf for inbound calls and only inbound audio direction)
4. Can two standalone ProSBCs use single TSBC-HW-TRANS-1372 (share)?
5. What happens to a new call if all resources of transcoding unit are already used? Is it rejected? I'm assuming G711a on both sides and only detecting DTMF.

[Admin]

You can use transcoding device for DTMF transcode too. If DTMF comes inband and need to be tanscode to RFC2833 you need transcoding unit.

1. Can I enable transcoding for single NAP and not others?

You can assign different profiles to different NAPs. In one profile you can select DTMF mode as Inband on other Profile you can select RFC2833.
2. Can I enable transcoding only for calls in one direction on NAP? I need to process only inbound calls with inband DTMF to RFC dtmf. I don not need transcoding on outbound calls.

No it is not possible. If transcoding need it it will work.

3. Can I enable transcoding only for one direction of audio to conserve resources for more calls? (inband DTMF to RFC dtmf for inbound calls and only inbound audio direction)

Same as answer 2.
4. Can two standalone ProSBCs use single TSBC-HW-TRANS-1372 (share)?

Not possible. Each device needs different transcoder.

5. What happens to a new call if all resources of transcoding unit are already used? Is it rejected? I'm assuming G711a on both sides and only detecting DTMF.

Calls will not transcoded

[AndrzejP]

Hi,

thank you for answers. I need to clarify particular scenario.
Let's assume:
I've got prosbc with transcoding unit.
NAP A with profileA and B with profileB.
profileA has "Allow audio transcoding" ON.
profileB has "Allow audio transcoding" OFF.

Both profiles have "DTMF relay scheme" set to: 1.Relay DTMF according to RFC2833 2. Relay DTMF in band.

There is inbound call to NAP A routed to NAP B with and negotiated RFC2833.
However DTMF is sent in-band and not as negotiated RFC2833.

In this case, would in-band DMTF be transcoded to RFC2833, or not due to the negotiated RFC2833? Technically speaking both call legs have negotiated compatible DTMF mode

Problem I'm trying to solve is some calls  - 10% - have in band DTMF, but RFC2833 is negotiated in SDP Rest of the calls is proper and I'm receiving DTMF in RFC2833.

[Admin]

Transcoding will work when it need it. If you negotiated DTMFs with RFC2833 and one side start to send DTMF in inband in this case transcoding will work. You can decide how transcoding will work with the profiles.

[AndrzejP]

Thank you for the answers