---
title: "Disable SIP ALG to improve ServiceTitan call quality"
slug: "disable-sip-alg-to-improve-servicetitan-call-quality"
updated: 2026-04-26T18:50:27Z
published: 2026-04-26T18:50:27Z
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.servicetitan.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Disable SIP ALG to improve ServiceTitan call quality

## Overview

Use this article to turn off the *Session Initiation Protocol Application Layer Gateway* (SIP ALG) on your router or firewall. Disabling it helps prevent dropped calls, one-way audio, and failed transfers in ServiceTitan.

---

### 

#### Who uses this feature

- Administrators
- Applies to all business types
- Applies to all trades

## Things to know

- SIP ALG is a network setting on your router or firewall that tries to help VoIP traffic but often breaks modern cloud systems.
- Disabling SIP ALG is done outside of ServiceTitan, on your network equipment.
- If you are not comfortable changing network settings, contact your IT provider or ISP before making changes.

## Key terms for this workflow

#### Session Initiation Protocol Application Layer Gateway (SIP ALG)

A feature on many routers that watches and edits internet phone (VoIP) traffic to help calls work through the firewall. Modern cloud phone systems like ServiceTitan already handle this themselves, so SIP ALG often breaks calls instead. This causes issues like one-way audio, dropped calls at set time marks, failed transfers, or phones that look registered but don't ring.

#### Network Address Translation (NAT)

A function on your router that lets many devices in your office (each with its own private IP address) share a single public IP address on the internet. It works like a doorman in an apartment building, keeping track of which device requested what, and normally works well with VoIP until extra features like SIP ALG start changing what's inside the call traffic.

#### Packets

Small chunks of data that carry information across the internet, each with a payload and a header. Payload contains the content, such as part of a web page or a tiny slice of voice audio and the header shows where it came from and where it's going. Routers usually only read the header to move packets along, but features like SIP ALG open them up and rewrite call details inside, which is what can cause ServiceTitan call problems.

## Disable SIP ALG for your network

#### Step 1: Confirm this workflow applies to you

You might need to disable SIP ALG if you see one or more of these symptoms:

- Calls where only one side can hear audio.
- Calls that drop at a consistent time, such as 10 seconds or 15 minutes.
- Transfers that fail immediately when you send a call to a colleague.
- Phantom calls that appear in logs but never ring a device.

#### Step 2: Identify your router or gateway

1. Find the main router or gateway that provides internet to your office. This might be an ISP-branded device (for example, AT&T, or Verizon) or a separate business router.
2. Look for the **manufacturer** and **model number** on the label. You'll use this to find the correct section below.

#### Step 3: Log in to your router

1. From a computer connected to your office network, open a web browser.
2. In the address bar, enter the router's IP address. Common addresses include:
  - 192.168.1.1
  - 192.168.0.1
  - 10.1.10.1
3. When prompted, enter the administrator username and password.
  - Check the label on the device or your IT documentation.
  - If you don't know the credentials, contact your IT provider or Internet Service Provider.

#### Step 4: Turn off SIP ALG (generic steps)

Use these general steps if your router brand is not listed below or if the menus look different.

1. After you sign in, go to the advanced configuration or firewall area. Look for menu names such as:
  - Advanced
  - Firewall
  - Security
  - WAN
  - NAT or NAT Passthrough
2. In that area, look for a setting named **SIP ALG** or similar. Common names include:
  - SIP ALG
  - SIP Passthrough
  - SIP Helper
  - SIP Transformations
  - VoIP ALG
3. Turn the **SIP ALG** setting off.
4. When finished, save your changes.
5. Reboot your router if there is an option to do so. If not, you can power-cycle it manually.

If your router does not show any SIP ALG or VoIP ALG setting, check the manufacturer's support site or contact your IT provider.

## Disable SIP ALG by router brand

> [!NOTE]
> **Note:** This information is sourced from manufacturer websites and user forums and has not been independently verified by ServiceTitan. The steps for your specific model or batch may differ. You may need to contact the manufacturer or your Internet Service Provider, or consult additional online resources, to get the current instructions.

| **Router Manufacturer** | **Steps to Disable SIP ALG** |
| --- | --- |
| Actiontec | 1. In the router menu, go to **Advanced**. 2. Confirm any warning that appears. 3. Select **ALGs**. 4. Ensure **SIP ALG** is turned off. 5. Click **Apply**. 6. (Optional) Return to *Advanced* and select *Remote Administration* if needed for your IT team. |
| Adtran | 1. In the web interface, go to **Firewall > Firewall** or **ACLs**. 2. Select **ALG Settings**. 3. Turn **SIP ALG** off. 4. Click **Apply**. > [!TIP] > **Tip:** If you manage Adtran devices by command line, work with your IT provider to run the following command: *no ip firewall alg sip*. |
| Arris | **Most Arris gateways** 1. In a browser, go to http://192.168.0.1. 2. Log in with the administrator username and password. 3. Go to **Advanced > Options**. 4. Unselect **SIP** to turn SIP ALG off. 5. Click **Apply**. **Arris BGW210** 1. In a browser, go to http://192.168.1.254. 2. Authenticate using the *Device Access Code* from the modem label. 3. Go to **Firewall > Advanced Firewall**. 4. Turn **SIP ALG** off. 5. Turn **Authentication Header Forwarding** off. 6. Turn **ESP Header Forwarding** off. 7. Save your changes. |
| Asus | 1. In the side menu, under *Advanced Settings*, select **WAN**. 2. Click the ***NAT Passthrough*** tab. 3. Set *SIP Passthrough* to **Disable**. 4. Click **Apply**. |
| AT&T U-verse Pace 5268AC gateway | This device does *not* allow you to turn off SIP ALG directly. 1. Contact AT&T or your IT provider. 2. Ask them to put the AT&T gateway in **Bridge Mode** or **IP Passthrough** mode so it acts only as a modem. 3. Have them install a separate business-grade router behind it. 4. Disable SIP ALG on the new router using that manufacturer's instructions. |
| Cisco | Work with a qualified IT provider before running CLI commands on Cisco equipment. **General or enterprise-class Cisco routers** 1. On the device CLI, enter configuration mode. 2. Run: 1. *no ip nat service sip tcp port 5060* 2. *no ip nat service sip udp port 5060* **Cisco PIX** 1. On the device CLI, enter configuration mode. 2. Run: 1. *no fixup protocol sip 5060* 2. *no fixup protocol sip udp 5060* **Cisco ASA** 1. Find policy-map global_policy. 2. In class inspection_default, run *no inspect sip*. 3. Save the configuration. |
| D-Link | **General D-Link routers** 1. In the web interface, go to ***Advanced Settings***. 2. Find the *Application Level Gateway (ALG) Configuration section*. 3. Clear the **SIP** setting. 4. Save your changes. **D-Link DIR-655 example** 1. Go to **Advanced > Firewall Settings**. 2. Clear **Enable SPI**. 3. Set **UDP Endpoint Filtering** and **TCP Endpoint Filtering** to **Endpoint Independent**. 4. In *Application Level Gateway Configuration*, clear **SIP**. 5. Save your changes and reboot the router. |
| Fortinet | Work with your IT provider before changing firewall helpers on Fortinet devices. 1. Use the following commands from the CLI interface: 1. *config system session-helper* 2. *show system session-helper* 2. Identify the entry for SIP (often entry 12) and delete it. **Example:** *delete 12*. 3. Confirm its deletion by executing this command: 1. *show system session-helper* |
| Linksys | **Linksys Smart Wi-Fi (E-series)** 1. In the side menu, select **Connectivity**. 2. Click the **Administration** tab. 3. In the *Application Layer Gateway* section, clear **SIP**. 4. Save your changes. **Older Linksys models** 1. Go to the **Advanced** section of the admin screen. 2. Disable the **SIP ALG** feature. |
| Mikrotik | On Mikrotik devices, SIP ALG is called *SIP Helper*. **Winbox GUI** 1. Go to **IP > Firewall**. 2. Click the **Service Ports** tab. 3. Disable **SIP**. > [!TIP] > **Tip:** You may also run this command from the terminal: */ip firewall service-port disable sip*. |
| Netgear | **Netgear Genie interface** 1. Click the **Advanced** tab. 2. Expand **Setup** and select **WAN Setup**. 3. Check **Disable SIP ALG**. 4. Save your changes. **Other Netgear models** 1. Under *Security* or *Firewall*, open **Advanced Settings**. 2. Turn **SIP ALG** off. 3. Find *Session Limit* or *UDP timeout* settings. 4. Increase the **UDP timeout** to 300 seconds. 5. Save and reboot the router. |
| SonicWall | 1. In the menu, go to **System Setup > VoIP**. 2. Select **Enable Consistent NAT**. 3. Clear **Enable SIP Transformations**. 4. Click **Accept** to save. 5. To adjust UDP timeouts, go to **Firewall Settings > Flood Protection**. 6. On the *UDP* tab, set the default UDP connection timeout to 300 seconds. 7. Click **Accept**. |
| TP-Link | **Newer TP-Link (Archer series)** 1. Click the **Advanced** tab. 2. Select **NAT Forwarding**. 3. Turn **SIP ALG**, **RTSP ALG**, and **H323 ALG** off. 4. Click **Save**. **Older TP-Link devices (Telnet)** 1. Connect to the device via Telnet. 2. Run *ip nat service sip sw off*. 3. Save your configuration and reboot the router if needed. |
| UBEE | 1. In the router interface, go to **Advanced > Options**. 2. Disable **SIP** and **RTSP**. 3. Click **Apply**. |
| Ubiquiti | **UniFi Security Gateway (USG)** 1. Sign in to the UniFi controller. 2. Go to **Routing & Firewall**. 3. Select the **Firewall** tab, then **Settings**. 4. Disable **H.323** and **SIP**. 5. Click **Apply Changes**. **EdgeRouter (ER-X and similar)** **Config Tree** 1. In the web UI, select **Config Tree**. 2. Go to ***System* > *Conntrack* > *Modules* > *Sip***. 3. Select **Disable**. 4. Click **Preview**, then **Apply**. **CLI** 1. From the administrative interface, select CLI. 2. Enter these commands into the terminal: - *Configure* - *set system conntrack modules sip disable* - *set system conntrack timeout udp stream 300* - *set system conntrack timeout udp other 300* - *Commit* - *Save* - *Exit* |
| Verizon FiOS G1100 | This device does **not** allow you to disable SIP ALG directly. 1. Contact Verizon or your IT provider. 2. Ask them to configure the FiOS gateway to act as a modem only. 3. Install a business-grade router behind it. 4. Disable SIP ALG on the new router using that manufacturer's steps. |
| ZyXEL | **ZyWALL / USG60** 1. In the web interface, go to **Configuration**. 2. Select **Network > ALG**. 3. Turn **Enable SIP ALG** and **Enable SIP Transformations** off. 4. Click **Apply**. **ZyXEL C1000Z / C1100Z (CenturyLink)** 1. Go to **Advanced Setup**. 2. Select *SIP ALG*. 3. Set **SIP ALG** to **Disable**. 4. Click **Apply**. **ZyXEL P600 (Telnet)** 1. Open a Telnet session to 192.168.1.1 and log in with the device password. The default password is **1234**. 2. Type **24** and press **Enter**. 3. Type **8** and press **Enter**. 4. Run: *ip nat service sip active 0* 5. Press **Enter** again and exit. |

## Reboot and test ServiceTitan calls

1. After you turn SIP ALG off, reboot your router or firewall.
2. Reboot your desk phones and any computers running a softphone.
3. Sign in to ServiceTitan and open your Contact Center Pro or softphone workspace.
4. Place several test calls:
  - Inbound calls to your main line.
  - Transfers between agents.
  - Outbound calls to external numbers.
5. If calls complete successfully without one-way audio, drops, or failed transfers, SIP ALG is likely resolved.

If issues continue, share this article and your test results with your IT provider or VoIP vendor so they can review other network causes (QoS, bandwidth, or cabling).

## Want to learn more?

- See [Best practices for optimal VoIP experience and reliability](/v1/docs/best-practices-for-optimal-voip-experience-and-reliability)
- See [Contact Center Pro network recommendations and setup](/v1/docs/contact-center-pro-network-recommendations-and-setup)
- See [Phones Pro network recommendations and setup](/v1/docs/phones-pro-network-recommendations-and-setup)