Information on the phone systems

The telephone installation at DESY in Hamburg has about 4,500 extensions and offers a wide range of communication possibilities with lots of special features. The phone system composes of analogue (push-button dialling phones) as well as digital (ISDN and IP) phones with a voice mail recorder, a fax server and further special functions. The DESY telephone installation in Hamburg is interconnected with those of DESY in Zeuthen, of the EMBL (European Molecular Biology Laboratory) as well as the administration net of Hamburg (e.g. University of Hamburg).
The classical telephone system at DESY in Hamburg composes of an elder system of the type “Integral I333” and a newer one of the type “Integral I55”, both supplied by the company Avaya.
The elder Integral I333 supports solely analogue extensions (about 200); in contrast the newer Integral I55 supports analogue as well as digital extensions.
Since February 2005 a third system has been added: a VoIP-installation based on the Cisco Callmanager. This part of the telephone system connects today more than 2,100 IP-phones.
In order to simplify the complex telephone system, the declared aim is to replace the elder Integral I333 completely by IP-phones. The only change for the user is the replacement of his present phone with a modern IP phone (with additional comfort functions, such call list and calling number display). A cut-off of the Integral I55 is neither planned nor wanted at the moment, because due to the technical independence of the IP Data net, it is necessary to keep the redundancy of the IP-data. Modern functions such as softphones, outlook-integration, XML-services, video calls are realized primarily on IP phones.
The telephone interconnection is connected with the public telephone network via four classical telecommunication hubs (PMX) resulting in 120 parallel lines for external calls.
Other connected components are: a PIN-Code-Server, that enables to make private calls via personal accounts, an account settlement system for the hostels and, last but not least, three message exchanges in building 11 and at the gate keepers.


Key number





Callback at busy signal


Delete callback at busy signal


Mobile phones at DESY Hamburg or Zeuthen VPN


Privat-Gespräch mit Pin-Code (*) (Antrag deutsch/englisch)


Rufumleitung variabel ein


Rufumleitung variabel aus




General Löschung