LMR Interoperability


Interoperability is likely the most important element to any broadband PTT solution.  ESChat has invested more in ensuring our service is interoperable across wireless networks, as well as any LMR network, Dispatch system and Logging Recorder solution.

ESChat interoperability can be broken down into two primary groups: ‘Inter-Carrier Interoperability’ and ‘Inter-System Interoperability’.

Inter-system interoperability involves connecting disparate LMR technologies, including analog trunked, P25, and other digital LMR technologies including DMR, TETRA, and NXDN. This also includes connecting across multiple frequency bands, such as VHF Low, VHF High, UHF, 700MHz & 800MHz. Inter-system interoperability issues have mainly been solved using appliance based third-party solutions. These solutions, from companies like JPS Interop, are very effective at providing communication across LMR networks, regardless of LMR technology and frequency band.

Inter-Carrier interoperability problems are the result of the widespread adoption of Broadband PTT technologies in the commercial and government marketplace. There are two basic categories of broadband PTT solutions: ‘Carrier Integrated’ and ‘Over the Top’.

The ESChat Ecosystem

Wireline Interoperability

In the public safety space, hybrid P25 and broadband PTT solutions are being deployed, using the P25 Inter subsystem interface (ISSI) for integration.  ISSI was designed to connect multiple P25 systems together, however it can also be used to connect P25 and non-P25 systems. In this model, broadband PTT users are assigned P25 Unit IDs, and while talking on P25 channels, floor-control, priority and preemption are managed by the P25 system. ISSI integrated hybrid networks also support passing of Unit IDs, Private Calls, Group Calls, Emergency Calls, transparent integration with CSSI connected Dispatch Consoles and Call Logging systems. End-to-End encryption between smartphones, radios and consoles is also supported, including key management via the P25 Key Management Facility (KMF).

As a member of the community of businesses that provide communication solutions to public safety, we at ESChat strive to make the ubiquitous communication network a reality. Inter-agency, inter-system, inter-vendor and inter-carrier interoperability must all be supported. This is our mission, and it is all for the benefit of public safety.

Wireline Unit ID Management

Wireline Group ID Management

Gateway Based Interoperability: Radio Over Internet Protocol (RoIP)