The ability of persons to monitor Garda radio communications by means of scanners and similar devices has been a security concern of the Garda Síochána for some time.
The current Garda radio network is not one, single integrated system but rather a number of distinct radio communications systems that are interlinked to varying degrees. They can be categorised into four broad system types: the "provincial system", i.e., the system used outside Dublin; the Dublin metropolitan area system; the Cork system; and special services systems for national organised groups.
Of these four, only the Cork system and the special services systems offer the Garda Síochána secure, encrypted radio communications.
However, as the special services systems are based only on ad hoc systems rather than network arrangements, the only part of the radio network that offers secure communications is the Cork system, primarily because, during the preparation of its specification, the requirement for encryption was included from the start. However, even here, because the transmission system in use by the Garda Síochána is based on analogue technology, encryption on the Cork system has resulted in some, foreseen degradation in voice quality.
As a consequence, providing secure radio communications for the force in effect means providing encrypted radio communications. From a technical perspective, the current Garda radio network, based as it is on analogue technology, does not provide a ready means of encrypting Garda communications. Hence, it is necessary, to all practical intents, to have in place a digital system of radio communications before encryption and, hence, security can be made readily available.
With this and other considerations in mind, I recently secured the approval of the Government to replace the existing Garda radio network with a new digital system. The new system is not only based on digital technology but, more than this, it is based on the TETRA standard. TETRA, which is an acronym for Terrestral Trunked Radio, was developed as a standard under a mandate from the European Commission and uses some of the technologies developed for GSM mobile phone systems, but enhanced to meet the requirements of emergency services.