Nupoint Inbound Fax via SIP trunks

[Waldosworld]

Platform: MiVoice Business Express
Trunk Media: SIP
The EG for Nupoint does recommend TDM lines however the cluster is all virtual platforms.
Internal fax calls to the Nupoint are received successfully and delivered to user.
External inbound faxes to the Nupoint, fail 100%, have tried from different fax machines and pc's
That said, a Grandstream SIP device with fax machines connected working fine.

 

[Lundah]

What protocol is the SIP provider using? I suspect they may only support T.38, which would explain what you're seeing. For NP Fax to work on a vMCD, I think you need to be using G.711.

 

[Waldosworld]

We are using G.711, you cannot license avMCD for T.38. Will have to check with the carrier if they have T.38 enabled by mistake.

 

[Waldosworld]

Checked carrier work order they do not even support T.38

 

[Lundah]

Might need to do a packet capture and see what's in the SIP headers being exchanged with the carrier.

 

[bribob]

Haven't touched the MiVB Express so take these comments with a grain of salt:

Does your SIP trunk terminate to an MBG first? --> Does the SIP provider (audio stream) know how to reach the NuPoint IP?
Is the NuPoint server sitting on the same subnet as all the other VoIP devices?


-b

 

[Waldosworld]

Performed test calls and the wireshark capture, G.711 codec as expected, status completed, however the fax status is failed.
The SIP trunk terminates to a vMBG first and same subnet.
Standard VOIP calls no issues.

 

[bribob]

Where did you take your capture (Firewall/vMBG/vMCD/NuPoint)? Care to post an edited text version (if confidentiality is needed)?

Can you capture directly on NuPoint to confirm 2 way audio?

VCCS from NuPoint might give you some more information:
From the (root) CLI of the NuPoint --> # vccs -W
Initiate an inbound external fax
CLI --> d (for dump, note the location /tmp/vccs_001.vcs)
CLI --> x
CLI --> #vccs -d /tmp/vccs_001.vcs
Analyze


-b