> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-web-portal-category/nap-profiles/fax-settings/configure-fax-vbd.md).

# Configure Fax VBD

To enable VBD:

1\. Select Profiles from the navigation menu.

<figure><img src="https://docs.telcobridges.com/w/images/8/8e/ConfigureFaxPassthrough_0.png" alt=""><figcaption></figcaption></figure>

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2\. Click Create New Profile

<figure><img src="https://docs.telcobridges.com/w/images/3/37/ConfigureFaxPassthrough_1.png" alt=""><figcaption></figcaption></figure>

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3\. Enter a name for the Fax Profile.

* Click Fax/Modem Relay to expand the view.

<figure><img src="https://docs.telcobridges.com/w/images/b/b9/ConfigureFaxVBD_0_A.png" alt=""><figcaption></figcaption></figure>

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4\. Configure the settings:

* Set Enable Fax/Modem Relay to enabled.
* Set Detection Mode to Standard.
* Set Relay Mode to Passthrough.
* Set Switch to FAX relay upon CNG tone to checked.
* Select a codec. For example silence suppression

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You can set one or both of the following two parameters:

* Support V.152 VBD
* Force V.152 VBD

<table><thead><tr><th width="200">Support V.152 VBD</th><th width="200">Force V.152 VBD</th><th width="200">Description</th></tr></thead><tbody><tr><td>Enabled</td><td>Disabled</td><td>Will negociate the gpmd parameter in the SDP.</td></tr><tr><td>Disabled</td><td>Enabled</td><td>Will always use VBD.</td></tr><tr><td>Enabled</td><td>Enabled</td><td>Will accept VBD without negociation and will negociate for it on an outgoing fax.</td></tr></tbody></table>

<br>

<figure><img src="https://docs.telcobridges.com/w/images/e/ea/ConfigureFaxVBD_1.png" alt=""><figcaption></figcaption></figure>

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5\. Verify that the Profile was successfully created message is displayed.

<figure><img src="https://docs.telcobridges.com/w/images/1/19/ConfigureFaxVBD_2.png" alt=""><figcaption></figcaption></figure>


---

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