Interoperability for Public Safety Networks
It is widely recognized that efficient communications are of paramount importance in order to have effective Public Protection and Disaster Relief (PPDR) operations. Indeed, there is great interest from governments and organizations involved in PPDR toward the evolution of existing wireless systems for critical communications to have higher communication capacity. However, an efficient communication system depends also on the capability of providing service interoperability among different networks. Interoperability barriers among the communication systems of various PPDR organizations are present both at national level (among public safety organizations of the same region or nation) and among PPDR organizations from different nations. Interoperability barriers are usually based on historical reasons: communication networks are created by each PPDR organization with a vertical structure to address the specific requirement of the organization. In some cases, interoperability barriers are also due to security reasons. In an effort to secure and protect the network data, cryptography mechanism and cryptography keys are different even in networks based on the same technology. Interoperability barriers are more often operational than technical. Common procedures and organizational schemes during a national disaster may be defined at national level, but rarely at international level. Cross-border operations are particularly affected by lack of interoperability because of linguistic barriers or because national organizations use different network technologies. A critical issue is the lack of roaming capability, which is available for users of commercial networks (e.g. GSM/UMTS), but it is not available for the PPDR community. As a consequence, a PPDR officer moving from one dedicated PPDR network to another will lose the communication instead of being transferred to the new network.