FECL 13 (March 1993):

DIGITAL NETWORKS TOO SAFE?

The german authorities complain about their problems withintercepting the new digital mobile telephone networks. They say, it is impossible for them to tapp conversations on both new digital networks, D1 (operated by the state-owned Telekom) and D2 (operated by the private Mannesmann Mobilfunk).

According to reports in the Süddeutsche Zeitung and in Wirtschaftswoche the problem lies in the lack of software in the transmitter stations. For both systems, such software has not yet been produced. This constitutes a breach of a provision in the network licences under which interception must be possible for the authorities at any time. The German licence appears to be quite to meet requirements of the "FBI-proposal" in the USA.

Another problem for the security services lies in the operating standard all European digital mobile phone vendors have agreed upon. The GSM (Global System for Mobile Communication) standard has a feature that to some degree encrypts all traffic at least between the transmitter and the user's phone, thus barring third persons access to the conversation by interception of theradio-transmitted part of the telephone call.

The effectiveness of this encryption algorithm is however questionable, as its initial purpose within the GSM was to pack more traffic to a restricted number of frequencies and not to provide tapping-proof telecommunication.

The GSM has been quite successfully exported not only throughout Europe, but to other countries as well, such as Iran, South Africa and the Peoples Republic of China. This particularly worries at least the German security services, as it jeopardises their eavesdropping capabilities in these countries. They now press for stringent export controls on the encryption feature of GSM-based mobile telephone equipment.

The internationalisation of GSM-based systems has led to curiosities even within Europe. While the german network vendors telekom and Mannesmann agreed on interception, it is difficult to enforce interception within Europe. This is an effect of the opening of the common European market. It is now possible, e.g. for a german, to subscribe to one of the 26 European mobile phone companies. While this German user can now get access to the mobile phone network from anywhere in Europe, it has become even more difficult to enforce a German judge's order to intercept his/her phone calls made through a non-German company, as European regulations pertaining to this matter do not exist.

German security authorities are now negociating treaties with their EC neighbours aiming at EC-wide regulations on interception.

 

 

Comment

For once, technical development has improved communication privacy - at least for the few happy who can afford a digital mobile phone. This is, indeed, pleasant news. This undesigned victory for the cause of civil liberties is however unlikely to last. German mobile telephone companies e already working hard on software capableof putting an end to interception-free phone calls. For all that, the technical "deficiency" of the GSM will have contributed to some transparency of international intelligent activities. We now know: Germany's eavesdropping activities are world-wide.

Ingo Ruhmann, FIFF

 

Contact: FIFF (Forum of Computer professionals for peace and social responsibility), Reuterstr. 44, D-5300 Bonn 1, tel: +49/228 219548, fax: +49/228 214924