Project 25 (P25) land mobile radio (LMR) systems provide critical tactical and emergency communications capabilities to public safety agencies nationwide. The P25 Standards that define the technical foundation on which these interoperable systems rely are “built for public safety by public safety” and their development relies on collaboration between user and manufacturer communities. P25 is a set of standards that manufacturers can follow to ensure that their LMR equipment can interoperate (communicate) with equipment produced by other manufacturers. As a result, emergency responders and others who rely on LMR equipment and systems for critical communications can be assured that equipment from various manufacturers can be configured to work together.
The Who, What, When, Where, Why, and How of Encryption in P25 Public Safety Land Mobile Radio Systems
This document provides readers new to the topic of encryption with a discussion of basic issues related to establishing and maintaining effective encryption for Project 25 (P25) interoperable land mobile radio (LMR) communications systems.
Drawn from interviews with dozens of emergency communications practitioners nationwide, “Basics of P25” presents an overview of interoperability and P25.
Joint SAFECOM-NCSWIC P25 User Needs Working Group Fact Sheet (.pdf, 118.9 KB)
This fact sheet was created to provide an overview of the P25 UNWG’s history, structure, and recent products to support education and recruiting efforts across the public safety community to increase subject matter expert membership and involvement in SAFECOM, NCSWIC, and the P25 UNWG.
Project 25 Steering Committee Representative Handbook (.pdf, 1.04 MB)
This Handbook outlines the history, background, goals, and procedures of the P25 Steering Committee. Specifically, the document provides information on Steering Committee membership, voting, and P25 Standards development, and provides helpful recourses for new members or anyone interested in learning more about P25 Standards and the standards development process.
Statement of Project 25 User Needs (SPUN) (.pdf, 1.21 MB)
This document provides an overview of P25 systems and user needs for various P25 components and interfaces. Intended for public safety users and officials wanting to know more about P25 and P25 Standards development, the SPUN is an excellent resource for novice and veteran P25 users.
This video is an overview of the value and advantages of Project 25 (P25) as a long-term investment in a community’s public safety.
Link Layer Authentication (LLA) and Link Layer Encryption (LLE): Are You Really Secure? (.pdf, 275.32 KB)
This white paper summarizes the difference between LLA and LLE and emphasizes the need for encryption in the P25 environment. While both LLA and LLE sound similar and improve Project 25 security, they serve different purposes and are in different stages of development and adoption. LLA and LLE: Are You Really Secure? explains these features and their impact on secure public safety communications.
Project 25 Inter-RF Subsystem Interface (ISSI) and Console Subsystem Interface (CSSI) Primer (.pdf, 474.68 KB)
The Inter-RF Subsystem Interface (ISSI) and Console Subsystem Interface (CSSI) provides the ability to interconnect Project 25 radio frequency subsystems and console subsystems, even when systems are supported by different manufacturers. Given the inherent complexities in interconnecting radio frequency subsystems and navigating the implementation of standards-based technology, FPIC ISSI/CSSI Focus Group developed the Project 25 ISSI and CSSI Primer. The Primer provides a high-level overview and serves as a resource for current and prospective ISSI/CSSI users as they plan and implement these interoperability solutions.
Features and Functions
Emergency Alarm: Project 25 Inter-RF Subsystem Interface (ISSI) and Console Subsystem Interface (CSSI) Features and Functions (.pdf, 1.21 MB)
This white paper provides communications system planners, administrators, and technicians with instructive and actionable information about emergency alarms and emergency calls across ISSI and CSSI connections. The document provides technical explanations on how these features work, challenges public safety has witnessed, and implementation considerations for multi-system environments.
The Patching and Dynamic Regrouping: Project 25 Inter-RF Subsystem Interface (ISSI) and Console Subsystem Interface (CSSI) Features and Functions (.pdf, 313.17 KB)
This white paper provides communications system planners, administrators, and technicians with instructive and actionable information about patching and regrouping across ISSI and CSSI connections. The document provides technical explanations on how these features work, challenges public safety users have witnessed, and implementation considerations for multi-system environments.
This document includes a high-level overview of ISSI/CSSI technologies and a “Best Practices Checklist” to help explain the benefits of interoperability enhancements and the potential for infrastructure sharing for current and prospective ISSI/CSSI users as they plan and implement these interoperability solutions.
Best Practices for Planning and Implementation of P25 Inter-RF Subsystem Interface (ISSI) and Console Subsystem Interface (CSSI): Volume II (.pdf, 596.48 KB)
This document addresses technology, policy and partnerships for planning and implementing an ISSI or CSSI. The volume includes a best practices checklist intended to prompt practitioners to ask questions and consider strategic elements that may otherwise be overlooked during planning or implementation.
Land Mobile Radio (LMR)/ Long Term Evolution (LTE) Integration: Best Practices (.pdf, 432.81 KB)
This white paper provides emergency communications stakeholders with case studies and best practices from early LMR/LTE integration efforts at the state and local levels. Gathered through interviews with public safety practitioners who are pioneering LMR/LTE integration, the information aims at demonstrating the potential of these efforts and presents some of the lessons learned along the way.