ASTRID provides details of the plan to strengthen Brussels' TETRA network in the wake of 22 March attacks

Following an appearance before a parliamentary commission in Brussels ASTRID (the operator of Belgium's emergency services TETRA network) has released new details regarding the performance of its service on 22 March, when a series of bombings resulted in the deaths of 35 people.

Following an appearance before a parliamentary commission in Brussels ASTRID (the operator of Belgium’s emergency services TETRA network) has released new details regarding the performance of its service on 22 March, when a series of bombings resulted in the deaths of 35 people.

On the day of the attacks some of ASTRID’s radio assets in Brussels became saturated because of: 

  • The emergency’s exceptional nature – severe attacks were carried out successively at different locations in the space of a few hours and within a limited radius.
  • Emergency and security services came from around the country to assist and this required additional network capacity.
  • Commercial mobile phone networks became saturated, leading to an increased number of individual calls on the ASTRID network.

Following the attacks ASTRID immediately convened its crisis management team. It worked closely with the Federal Crisis Centre and the main network users, put its main infrastructure suppliers on standby, and deployed mobile base stations to temporarily boost radio capacity. ASTRID also, at the request of user organisations, logged 210 additional radios onto the network.

ASTRID and the User Advisory Committee have analysed the technical and operational aspects of the communications on the day of the attacks, respectively, and have put forward a number of action points and proposals.

Technical improvements
A series of short-term measures have been discussed with users, including faster deployment of mobile base stations and a clearer framework for managing communications with the Federal Crisis Centre.

  • Increasing the capacity of the radio network. Doing so for Brussels (or big cities) is possible by the end of 2016, but ASTRID will need additional frequencies. It is currently in discussions to obtain them.
  • Approval of ASTRID's business plan and the management contract to optimise and technically renew all ASTRID systems. Discussions on this subject have been initiated within the inter-cabinet working group.
  • New communications priority over data service broadband. ASTRID already offers emergency services a high-speed data transmission service via national roaming over the networks of three mobile phone operators (Blue Light Mobile). The aim is to extend this service to provide the possibility to establish priority voices communications not only via the ASTRID TETRA network but also over Blue Light Mobile.

The ASTRID users’ advisory committee’s overall conclusion states: "based on available data we can conclude that the capacity problems were caused by technical and operational aspects”. It went on to explain what it means by ‘operational aspects’: "the awareness and training of personnel still remain to this day a major critical success factor for optimal network operation and radio communications”.

Marc De Buyser, ASTRID's CEO, released a statement expressing the ASTRID team’s “deepest sympathy” to the bombings’ victims and their families, and its respect for the emergency and security services.

 “The extraordinary magnitude of this event had an undeniable and heavy impact on the commercial mobile networks, which resulted in a considerable increase of radio traffic on the ASTRID network," he said. "ASTRID did not suffer an outage. The radio, paging and control room systems remained functional at all times. However, the massive mobilisation of emergency services as well as the hundreds of simultaneous group calls did affect the performance of radio communication in Brussels.

"Shortly after the attacks the ASTRID base stations in the vicinity of the Maalbeek metro station reached maximum capacity, which made communication difficult from time to time. A number of users experienced delays or did not get access to group calls. Challenging and stressful moments like these inevitably lead to a higher number of push-to-talks." 

“TETRA technology is still the most appropriate technology," said De Buyser during an address to the parliamentary commission reflecting on the use of the network during the attack. “Both technical and operational improvements are important, defined together with all stakeholders, for better future communications."

The majority of this feature is based on a French statement produced by Astrid seen by TETRA Today. French translation and checking with the assistance of Carla Di Guardia. This article has been amended as the original version erroneously stated that the User Advisory Committee submitted technical proposals.