> For the complete documentation index, see [llms.txt](https://help.sipgate.de/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.sipgate.de/cloud-telefonanlage/en/using-sipgate/mobilfunk/was-ist-cell-broadcastnotfallwarnungen-auf-dem-handy.md). # What is Cell Broadcast – emergency alerts on your phone? #### **How does Cell Broadcast work and who is behind it?** Cell Broadcast is used for emergency alerts to all mobile phones in a specific risk area. You receive a notification with an alarm tone via the mobile network, regardless of the operating system or device brand. Unlike SMS or push notifications, Cell Broadcast messages are not limited to a phone number or app. The transmission of warning messages works similarly to broadcast signals, so the notification is sent directly to all mobile phones in the affected radio cell. The content of the messages is the responsibility of [the Federal Office of Civil Protection and Disaster Assistance (BBK)](https://www.bbk.bund.de/DE/Home/home_node.html), the respective interior ministries or disaster management authorities. They create and send the Cell Broadcast messages to communicate information about emergency alerts such as natural disasters, terrorist attacks or other dangerous situations to the affected population. #### **What role does sipgate play in Cell Broadcast?** The main goal of Cell Broadcast is to establish a new warning channel with high reachability. sipgate uses the existing network infrastructures and acts as an intermediary for transmitting the warning messages. #### **How can I receive the warning messages on my phone?** In general, most mobile phones and smartphones in Germany can receive alerts via Cell Broadcast without any additional settings. The general requirements for this are: * The operating system on your phone is up to date, for example iOS versions from 15.6.1 onwards (with the exception of iOS 16.0.x) as well as Android version 11 and above. * The phone is switched on and is not in airplane mode. * Your SIM card is activated. [Here you will find a list of compatible devices](https://www.bbk.bund.de/DE/Warnung-Vorsorge/Warnung-in-Deutschland/So-werden-Sie-gewarnt/Cell-Broadcast/Empfangsfaehige-Geraete/empfansfaehige-geraete_node.html), that can receive Cell Broadcasts. #### **What information is transmitted in warning messages?** The contents of the notification can vary, but in general emergency alerts can be defined based on the following characteristics: * These are text messages of up to 500 characters that are displayed on the phone screen with a loud signal tone. * The messages contain the name of the authority that triggered the alert. Genuine warning messages also contain a link to an official warning portal, where detailed information about the danger is provided. * Since this is not an SMS, no sender number is displayed and it is not possible to reply to the notification. You are also not prompted to open a website or install an app. * A warning message contains information about the existing danger as well as clear instructions on what to do. #### **How can I turn the Cell Broadcast function on and off?** In most cases, the Cell Broadcast function is already activated on your phone. There are various alert levels for messages, and you cannot turn off notifications for the highest level. In other cases, you can customize the settings on your phone individually. It is important that the current operating system is installed on your phone. You can then follow this path: **settings** **➔** **Notifications** **➔** **Emergency alerts** or **Cell Broadcast alerts** or **Alerts**. There you can specify whether you want to receive warning and test messages. [You can find a detailed explanation for iOS and Android devices here](https://www.telefonica.de/netze/mobilfunknetz/cell-broadcast.html#android). On other devices and older iOS or Android versions, users may need to activate the function. Please note device-specific settings or the manufacturer's instructions. #### **Are my personal data transmitted or processed for the emergency alert?** The sending of emergency notifications is anonymous and similar to broadcast transmission. This means that no personal information such as private mobile phone number and location data can be collected and processed. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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