Advances in mobile communications from 3G to 4G and further to 5G to support high speed, broadband and multimedia services for mobile devices have resulted in a growing worldwide effort to advance and modernise emergency communications based on mobile networks (e.g. 4G/LTE) for the provision of multimedia emergency services with high efficiency and security.
Considering either a long-term evolution from traditional Private Mobile Radio (PMR) networks such as TETRA to advanced mobile networks (e.g. 4G/LTE) for future emergency services, or an integrated solution between TETRA and LTE for enhanced emergency services, there is an important issue regarding interoperability between TETRA and LTE, which needs to be addressed by emergency communications professionals.
The GERYON project
The EU FP7 GERYON (Next Generation Technology Independent Interoperability of Emergency Services) project aims to provide an interoperability solution for different emergency networks including PMR networks (e.g. TETRA and TETROPOL) and advanced 4G mobile networks (e.g. LTE/WiMAX/Wi-Fi).
GERYON utilises 3GPP specified IP Multimedia Subsystem (IMS) to enable the interoperability between different communications networks for the provision of emergency services.
It is intended to support a variety of emergency services, including basic services such as push-to-talk, group call, dynamic group call, prioritisation of calls, call dispatch and location services, and enhanced multimedia services such as real time video transmission, picture transmission, real-time message interchange and red button services.
The key objective of GERYON is to facilitate communications among first responder services such as fire-fighters, police and ambulances using either TETRA terminals or smartphones, or emergency communications between citizens using smartphones (e.g. with red button function) and Public Safety Answering Points (PSAPs).
Since the start of the project in December 2011, GERYON is now at the halfway point of its journey towards developing a demonstrable prototype for its proposed interoperability approach based on IMS. Within a consortium of seven partners from four European countries (i.e. Spain, Greece, France and the UK), a GERYON system has been set up, as shown in Figure 1 (a conceptual diagram above).
The IMS-based GERYON cloud consists of the GERYON Enhanced Management System (GEMS), which is the central management logic of the GERYON system and is connected directly to the Core IMS zone. Mobile terminals are equipped with GERYON-Droid (GDroid) applications enabling them to establish connections with the GERYON domain via 4G/LTE or WiFi networks.
A GERYON Enhanced Gateway (GEGW) is utilised for the interconnection between the TETRA system and the GERYON domain. GERYON Media Gateway (GMGW) and GERYON Security Gateway (GSGW) are used for media transcoding and cross-ciphering when end-to-end communications are made across different networks using different media codecs and security schemes.
Public Safety Answering Point (PSAPs), in conjunction with the control room, serves as an operation centre (or call centre) to facilitate incoming calls for call transfer, call monitoring, group messaging and provisioning of dispatch and location services to first responders. Currently all connections between different clouds are made through the internet (via VPN) as shown in Figure 1.
In the past month, several trials on GERYON functionalities and services have been successfully carried out within the GERYON partners. For example, the first interoperability test was carried out between an LTE network which is located in Athens (Greece) and a TETRA system in Bilbao (Spain).
During the test, a full duplex international and inter-network call was established between two end-users (one used an LTE device while the other employed a TETRA terminal).
Further interoperability tests were carried out between a mobile device with WiFi access in Plymouth (UK) and a TETRA terminal in Bilbao (Spain) for a full-duplex call, and a call between a mobile device in Plymouth over WiFi connection and a smartphone in Athens over an LTE network.
These successful trials indicate the attainment of some of the major milestones in the journey to the development of a complete GERYON system.
The current project consortium consists of partners from Spain, Greece, France, and the UK from both industry and academia. The consortium was formed from leading experts in all key areas of emergency communications, digital content service delivery and exploitation, media processing, and network/information security.
GERYON also brings together SMEs like VIOTECH and CYS Group, commercial and public mobile network providers like COSMOTE and ITELAZPI, and leading-edge academia and research institutes, i.e. the University of the Basque Country, the University of Plymouth and NCSR Demokritos.
GERYON provides a platform and an excellent opportunity for these organizations to collaboratively work together to develop cutting-edge technologies and services for next generation emergency communications for Europe and beyond.
The evolution and information of the project can be followed at www.sec-geryon.eu/