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

# Understanding Zuper Connect calls

Zuper Connect uses Voice over Internet Protocol (VoIP) to make and receive calls over the internet. Your team needs an active internet connection to use Zuper Connect on the web, iOS, or Android.

This guide explains how calls reach your team, which internet connections work best, what happens to your phone number and SIM when you port a number, and how to troubleshoot common call quality issues.

## How a Zuper Connect call works

Zuper Connect uses VoIP technology to route calls and messages over the internet rather than through a traditional cellular voice network.

Here's how an incoming call reaches your team:

1. Your customer dials your business phone number from a mobile phone, landline, or another VoIP line.
2. The call enters the phone network and reaches Twilio, Zuper's carrier partner, which manages your number.
3. Twilio routes the call over the internet to Zuper Connect.
4. Zuper Connect rings the web, iOS, or Android app where your team member is signed in and online.
5. Audio travels in both directions over the internet connection until the call ends.

The quality of the internet connection used by your team directly affects call quality. Your customers do not need a special device or internet connection to call your business number.

> [!NOTE]
>
> Zuper Connect calls use Wi-Fi, Ethernet, or mobile data. They don't use your cellular voice minutes or your device's SIM.

## Why an active internet connection is required

Zuper Connect works only when the device running the app has an active internet connection.

Keep the following points in mind:

* **No internet connection, no calls:** If your device is offline, you cannot make outgoing calls, receive incoming calls, or send messages through Zuper Connect.
* **Weak connections affect call quality:** An unstable connection can cause choppy, delayed, or robotic audio.
* **Cellular signal bars do not indicate internet availability:** Signal bars indicate cellular coverage, while Zuper Connect requires a working Wi-Fi or mobile data connection.
* **Web app availability matters:** If the web app shows you as offline, incoming call notifications are routed to your mobile device only. Make sure your status and web app availability are configured correctly.

A stable internet connection is one of the most important factors in maintaining good call quality.

## Which internet connections work best

Zuper Connect supports Ethernet, Wi-Fi, and mobile data (4G or 5G). Ethernet generally provides the most stable connection, making it a good choice for office-based teams and call centers.

| Connection | Best for | Watch out for |
| - | - | - |
| Ethernet (wired) | Office desktops and call centers using the web app | Provides a stable connection. Requires an Ethernet cable and a router that allows call traffic. |
| Wi-Fi | Office and home use on laptops, phones, and tablets | Weak signals, network congestion, and distance from the router can affect audio quality. |
| Mobile data (4G or 5G) | Field teams using phones or tablets | Network delays and signal strength can vary by location. Calls also consume your mobile data allowance. |

### Tips for maintaining a stable connection

Apply these practices regardless of the connection type:

* **Stay on one network during a call:** Switching between Wi-Fi and mobile data during a call can interrupt audio.
* **Avoid crowded public networks:** Hotel, café, and shared guest Wi-Fi networks may block or restrict call traffic.
* **Limit bandwidth-heavy activities:** Avoid large uploads, video streaming, and downloads on the same network while making calls.
* **Test your connection:** Visit [networktest.twilio.com](https://networktest.twilio.com) to check two-way audio quality and determine how many simultaneous calls your network can support.

> [accordion] Does Zuper Connect provide a SIM or eSIM?
>
> No. Zuper does not provide a physical SIM card or eSIM for Zuper Connect numbers.
>
> Your Zuper Connect number works through the Zuper Connect web, iOS, and Android apps. You can use your existing phone, tablet, or computer to access the service.
>
> If you use a mobile device, its existing SIM or eSIM and mobile plan provide internet access when Wi-Fi is unavailable. However, the SIM does not carry your Zuper Connect number.
>
> > [!NOTE]
> >
> > If you need your business number to ring directly on a carrier SIM, such as on a basic phone without apps, Zuper Connect is not designed for that use case.

## What happens to your number and SIM when you port

When you port a phone number to Zuper Connect, the number moves from your existing carrier to Zuper Connect and becomes a VoIP number. Calls and messages to that number are then handled through Zuper Connect over the internet.

Porting transfers the phone number, not the SIM card or its associated services. Your previous provider determines what happens to the SIM and remaining services after the port is complete.

| Stage | What happens |
| - | - |
| Before the port | Your SIM continues to work normally. Keep your existing account and phone number active until the port is complete. |
| On the port date | Calls and messages to the ported number stop reaching your previous phone line and start arriving through Zuper Connect. |
| After the port | Your device can still use mobile data, apps, and other services included in your plan. However, the SIM or eSIM no longer carries the ported number. |

### What happens to your existing mobile line?

The outcome depends on how your phone number is associated with your carrier account.

* **The number is the only line on the account:** Your provider usually closes the line after the port. The SIM may stop working for calls and messages.
* **The number is part of a shared or family plan:** Your provider determines what happens to the SIM and remaining services. For example, the SIM may receive a new number or be removed from the plan.

Contact your existing provider to confirm what happens to your SIM, line, and plan after porting.

### What to do before porting

Before moving your number to Zuper Connect:

1. Update the phone number associated with banking apps, online accounts, and two-factor authentication services that send verification codes.
2. Inform your team and key customers about the date your number will move to Zuper Connect.
3. Ask your existing provider what will happen to your SIM, mobile line, and plan after porting.
4. Make sure every team member who needs to handle calls has the Zuper Connect app installed and is signed in.
5. Keep your existing account and phone line active until the port is complete.

### Can you keep your number on your existing SIM?

A phone number can be assigned to only one service at a time. If you want to continue using your number through your existing carrier SIM, consider one of these options:

> [accordion] **Option 1: Forward calls to Zuper Connect**
>
> Keep your number with your existing provider and configure call forwarding to a Zuper Connect number. Calls to your existing number will then be forwarded to Zuper Connect.
>
> Contact your carrier to configure call forwarding.

> [accordion] **Option 2: Port your number to Zuper Connect**
>
> Transfer your number completely to Zuper Connect. After the port, calls and messages are handled through the Zuper Connect apps. Your existing SIM may continue to provide mobile data and other services based on your carrier plan, but it will no longer carry the ported number.
>
> For required documents, porting timelines, and step-by-step instructions, see: [Porting Phone Numbers to Zuper Connect](https://docs.zuper.co/Zuper_Connect/Port-Number.md) for US numbers and [Porting Canadian Phone Numbers to Zuper Connect](https://docs.zuper.co/Zuper_Connect/Port-Number-2.md) for Canadian numbers.

## Texting, verification codes, and other considerations

Customers can call and text a Zuper Connect number just as they would any other business number. However, some third-party services treat VoIP numbers differently from traditional mobile numbers.

Consider the following when using Zuper Connect numbers:

### Business texting requirements

* **US local numbers:** Require [A2P 10DLC registration](https://docs.zuper.co/Zuper_Connect/10DLC.md) for reliable business text message delivery.
* **Toll-free numbers:** Require toll-free verification before business texting.

### Texting after porting

Although calls generally work once the port is complete, SMS routing may take an additional 2–3 business days.

Inform your team about this transition period so they know that text messages may not be delivered immediately after porting.

### Verification codes and OTPs

Some banks, applications, and verification services do not send one-time passwords (OTPs) or sign-in codes to VoIP numbers. Carriers may also block certain senders or number types.

If you do not receive a verification code:

* Check whether the service supports verification through VoIP numbers.
* If available, request a voice call verification code instead.
* Make sure the number rings directly to a person rather than going to voicemail or being routed through an extension.

For more information, see [OTP and 2FA Codes on Connect Numbers](https://docs.zuper.co/Zuper_Connect/OTP/2FA%20Verification%20Codes).

### Short-code messages

Zuper Connect numbers are not classified as mobile numbers. As a result, services that send messages through short codes, such as Google Voice, Facebook, and Skype, may not be able to deliver messages to them.

> [!TIP]
>
> Keep a personal mobile number associated with important accounts, especially banking and other services that require verification codes.

## Troubleshooting call quality and missed calls

Start with the connection. Most call quality problems trace back to it.

| Issue | Possible cause | What to do |
| :- | :- | :- |
| Choppy, robotic, or delayed audio | Weak or unstable Wi-Fi or mobile data connection | Move closer to the router, use Ethernet, or switch between Wi-Fi and mobile data before starting the call. |
| One-way audio or calls disconnecting after connecting | Firewall or router restrictions blocking call traffic | Try another network. Ask your IT team to review the [network requirements](#network-requirements-for-it-teams). |
| Incoming calls do not ring | Device is offline, status is set to offline, or app is closed | Check your internet connection, update your status and web app availability, and keep the mobile app signed in. |
| Problems occur only on a specific network | Network restrictions on office, guest, or hotel Wi-Fi | Test using mobile data or ask your network administrator to allow the required call traffic. |
| Problems occur only when using a VPN | VPN-related routing or additional network latency | Disconnect the VPN temporarily and test the call again. |

### Checklist before contacting support

Before raising a support request, verify the following:

* Your device is connected to the internet and can load websites.
* You have run the [Twilio network test](https://networktest.twilio.com) and recorded the results.
* The Zuper Connect app is updated and you are signed in. See [Device requirements](https://docs.zuper.co/Zuper_Mobile_Apps/Device_Requirements.md) for supported Android and iOS versions.
* You have tested the connection using another network.
* You have restarted the app or device and tested again.

If the issue persists, contact Zuper Support at [support@zuper.co](mailto:support@zuper.co). Include the following details to help the support team investigate:

* The phone number involved in the call.
* The date and time when the issue occurred.
* The connection type (Ethernet, Wi-Fi, or mobile data).
* The network test results.
* A brief description of the issue.

## Network requirements for IT teams

Zuper Connect calls require relatively little bandwidth. However, network stability is more important than connection speed when maintaining good audio quality.

Use the following network performance targets for devices and networks handling Zuper Connect calls.

| Measure | Recommended target | What it means for the call |
| - | - | - |
| Bandwidth per call | Approximately 40 kbps upload and 40 kbps download (approximately 100 kbps in each direction with older codecs) | Provides sufficient bandwidth for a basic call when other activities are not competing for network resources. |
| Latency (round trip) | Below 200 ms | Higher latency causes noticeable delays and overlapping conversations. |
| Jitter | Below 30 ms | Higher jitter can cause choppy or robotic audio. |
| Packet loss | Below 3% | Higher packet loss can cause missing or interrupted audio. |

Callers may notice delays when latency exceeds approximately 250 ms. At around 600 ms, call quality can become difficult to use.

### Firewall, VPN, and router considerations

Zuper Connect call audio normally travels over UDP. Network configurations that block UDP traffic can cause one-way audio or dropped calls.

Ask your IT team to review the following settings:

* Allow outgoing TCP and UDP traffic required for calls, including return traffic.
* Disable SIP Application Layer Gateway (SIP ALG) on the router, as it can interfere with call traffic.
* Review stateful packet inspection settings if calls experience connectivity issues.
* Check whether firewall rules or network policies restrict VoIP traffic.
* Temporarily disconnect VPN connections when troubleshooting call quality. VPNs can introduce additional latency or route traffic through a different region.

For connection testing, visit [networktest.twilio.com](https://networktest.twilio.com).

## Frequently asked questions

> [accordion] Do I need internet to use Zuper Connect?
>
> Yes. Zuper Connect requires an active Wi-Fi, Ethernet, or mobile data connection to make and receive calls and send messages.

> [accordion] Does Connect use my cellular voice minutes?
>
> No. Zuper Connect calls use internet data rather than your cellular voice minutes.

> [accordion] How much mobile data does a call use?
>
> Roughly 0.6 MB per minute, or about 36 MB per hour, before network overhead.

> [accordion] Will my ported number still ring on my old phone?
>
> No. The number moves to Zuper Connect and rings in the Connect apps. Your previous provider ends the line.

> [accordion] Is a ported mobile number a VoIP number?
>
> Yes. After the port it runs through Zuper Connect over the internet.

> [accordion] How long does a port take?
>
> In the US, local numbers typically take 7–15 days after the request is accepted, landlines 2–4 weeks and toll-free numbers 1–4 weeks. In Canada, ports typically take 1–2 weeks after the documents are accepted. Rejections add time. See the [US](https://docs.zuper.co/Zuper_Connect/Port-Number.md) and [Canadian](https://docs.zuper.co/Zuper_Connect/Port-Number-2.md) porting pages for details.


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