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Information Technology


A softphone is an application on a PC or mobile device that allows you to make calls with your HZB phone number from anywhere in the world. It behaves exactly like your desk phone. The softphone rings on a call to your HZB number and you can answer the call. In addition, you can also use the softphone to dial and call numbers. The called party will see your HZB number. This is also the significant difference to call forwarding. Your private phone number is not involved with the softphone in any case.

The data transfer on the softphone is completely encrypted over the IP network and the Internet. When using softphones on mobile devices, make sure that a sufficiently strong and stable data network is available. Fast movements (e.g. driving car) during a softphone call tend to lead to data transmission errors and thus make the call difficult to understand.

As softphone Linphone is available free of charge. Linphone is - like the HZB VoIP telephone system - open source and is officially supported by HZB IT. However, other softphones that support the international SIP standard and encryption via TLS and SRTP are also possible.

Linphone is available free for Windows, Linux, Mac, iOS, and Android.

A microphone or headset is mandatory for use on the computer.

As a telephone book you can use the "Corporate Directory" built into the Phone-Portal.
(However, please copy the phone numbers. Clicking on the handset icon in the corporate directory only works correctly on Polycom phones.)


Open your Phone-Portal. There, under "Softphone" you will find all the necessary login data you need to log on to the HZB telephone system.

Use Linphone on the device that is physically right in front of you or that is with you.
If you have installed Linphone on a PC in the HZB and access this HZB PC from outside the HZB via a remote connection (e.g. RDP), Linphone cannot be used in this way because the microphone signal of the local PC (in front of you) cannot be transmitted to the HZB PC via a remote connection. Instead, set up Linphone on the local PC in front of you.