A New Comprehensive Overview Document  is Now available from DHS CISA and the Federal Partnership for Interoperable Communications (FPIC)

 The Who, What, When, Where, How, and Why of Encryption in P25 Public Safety Land Mobile Radio Systems
was published in May 2023

CISA Encryption

 

The Full document can be downloaded using the link below:

The Who, What, When, Where, How, and Why of Encryption in P25 Public Safety Land Mobile Radio Systems 

This guide 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
LMR communications systems.  It is highly recommended for agencies planning, implementing, and managing an LMR encryption strategy

It combines and updates the content of three previously published
documents
issued by the Federal Partnership for Interoperable Communications (FPIC), SAFECOM,
and the National Council of Statewide Interoperability Coordinators (NCSWIC) in 2016:

Considerations for Encryption in Public Safety Radio Systems: This document examines why
encryption is necessary during critical operations. The document provides examples of how
encryption decreases the threat of compromise and reduces the risk to personnel safety
while providing protection of sensitive information.
Guidelines for Encryption in Land Mobile Radio Systems: This document provides information
that should be considered when evaluating encryption solutions to protect sensitive
operational or life safety radio transmissions.
Best Practices for Encryption in P25 Public Safety Land Mobile Radio Systems: This
document discusses encryption best practices for P25 LMR systems. The document also
provides an understanding of how basic key management parameters are related in P25 LMR
systems.

The document adds to the previous publications an extensive new section on encryption key
management, based on current proven encryption practices.

The overall objective is to further define and explain encryption and provide reliable guidance for
planning, implementing, and managing an LMR encryption strategy. Special emphasis is on two core
issues: 1) establishing common procedures—including governance, policies, and training—to preserve
user-defined interoperability and 2) managing encryption keys, the random strings of bits used to encode and decode data.