# Modifying FAX Relay Profile Settings

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

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

<figure><img src="https://docs.telcobridges.com/w/images/1/17/ProfileVoipFaxRelay_A_0.png" alt=""><figcaption></figcaption></figure>

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2- Modify settings as required.

<figure><img src="https://docs.telcobridges.com/w/images/d/d2/ProfileVoipFaxRelay_1A.png" alt=""><figcaption></figcaption></figure>

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](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-relay-enable-fax-modem-relay)
* [Detection Mode](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-relay-detection-mode)
* [Relay Mode](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-relay-relay-mode)
* [Modem vs. Fax distinction timeout](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-fax-modem-relay-modem-vs.-fax-distinction-timeout)
* [Fax/Modem tones detection duration](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-relay-fax-modem-tones-detection-duration)
* [Enable early Fax/Modem tone detection](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-relay-enable-early-fax-modem-tone-detection)
* [Switch to FAX relay upon CNG tone](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-relay-enable-switching-to-fax-relay-upon-cng-tone)
* [Expected CNG tones](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-relay-expected-cng-tones)
* [Switch to passthrough upon Bell ANS](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-relay-switch-to-passthrough-upon-bell-ans)

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T.38 Parameters

* [Use V.34](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-t.38-parameters-use-v.34)
* [Maximum Bit Rate](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-t.38-parameters-maximum-bit-rate)
* [Fill Bit Removal](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-t.38-parameters-fill-bit-removal)
* [Redundancy Count](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-t.38-parameters-redundancy-count)
* [Transmission level (-1dBm unit)](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-t.38-parameters-transmission-level-1dbm-unit)
* [Prevent direct invite in T.38](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-t.38-parameters-prevent-direct-invite-in-t.38)

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Fax/Modem Pass-through Parameters

* [Detection Type](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-fax-modem-pass-through-parameters-force-v.152-vbd)
* [Codec](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-pass-through-parameters-codec)
* [Jitter Buffer Depth](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-pass-through-parameters-jitter-buffer-depth)
* [Packet Duration](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-pass-through-parameters-packet-duration)
* [Use NSE](/configuration-details/configuration-parameters-all.md#parameter-fax-modem-pass-through-parameters-use-nse)
* [Support V.152 VBD](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-fax-modem-pass-through-parameters-support-v.152-vbd)
* [Force V.152 VBD](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-use-case/rtp-no-anchoring/creating-profiles/pages/MExpA9KQ1OYkRLRnmtUE#parameter-fax-modem-pass-through-parameters-force-v.152-vbd)


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