HRZ is your contact for telephony at TU Darmstadt. We are the right address for you if, for example, you want to apply for a new telephone, your entry in the TU-wide telephone directory needs to be changed or you have questions about the Jabber client. We differentiate between communication in the office with fixed end devices and mobile communication via Jabber.

From now on: Softphones instead of hardware telephones when moving into new buildings

Prior to the planned introduction of Unified Communications (UC) at TU Darmstadt, only software telephones (softphones) will be used from now on when moving into new or complete refurbished builings. These will replace the desk telephones that have been used until now.

The Jabber client is used as the softphone solution. Hardware telephones (classic desk telephones) are now only provided for employee workstations as an additional option for which a charge is made.

Necessary “function telephones” – where they are required by law (e.g. in first-aid rooms) – will continue to be provided.

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Mobile communication


The Jabber client offers telephony, video call, chat function, screen sharing and data exchange. All owners of a TU-ID can install and use the Jabber-Client.

This is how it works

Office communication


Register/change/deregister telephone

You want to apply for a new telephone, have changes to an existing telephone connection or want to deregister a telephone?

How it works