> For the complete documentation index, see [llms.txt](https://tmediadocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tmediadocs.telcobridges.com/other-pages/fax-and-media/modifying-fax-relay-profile-settings.md).

# Modifying FAX Relay Profile Settings

> **Applies to:** Tmedia 3.0, 3.2; SBC 3.0, 3.1

**To configure FAX Relay settings, do the following:**

1- Click **Fax Relay** in the Editing Profile window, to display the customizable options.

![ProfileVoipFaxRelay A 0](https://docs.telcobridges.com/w/images/1/17/ProfileVoipFaxRelay_A_0.png)

2- Modify settings as required.

![ProfileVoipFaxRelay 1A](https://docs.telcobridges.com/w/images/d/d2/ProfileVoipFaxRelay_1A.png)

3- To configure NSE, check the **Use NSE** checkbox.

**NOTE:**

If NSE exchange is possible (negociated in the SDP), the switch to passthrough will happen in the RTP stream and no longer wiil occur with a SIP re-INVITE. This implementation of NSE currently only supports a switch to passthrough, which means that you can have NSE packets switching to T.38.

* Click **Save**

### List of Parameters

Fax/Modem Relay

* [Enable Fax/Modem Relay](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Detection Mode](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Relay Mode](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Modem vs. Fax distinction timeout](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Fax/Modem tones detection duration](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Enable early Fax/Modem tone detection](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Switch to FAX relay upon CNG tone](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/sip#f)
* [Expected CNG tones](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Switch to passthrough upon Bell ANS](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)

T.38 Parameters

* [Use V.34](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#t)
* [Maximum Bit Rate](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#t)
* [Fill Bit Removal](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#t)
* [Redundancy Count](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#t)
* [Transmission level (-1dBm unit)](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#t)
* [Prevent direct invite in T.38](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/sip#t)

Fax/Modem Pass-through Parameters

* [Detection Type](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/sip#f)
* [Codec](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/sip#f)
* [Jitter Buffer Depth](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Packet Duration](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Use NSE](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem#f)
* [Support V.152 VBD](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/fax-modem-pass-through-parameters-support-v-152-vbd)
* [Force V.152 VBD](https://tmediadocs.telcobridges.com/telecom-references/parameter-reference/sip#f)


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