Project 25 Documents & Standards Reference
Encryption Services
Two encryption algorithms are available for use with P25 systems. DES is the oldest algorithm for which there are P25 standards documents. However, since May 2005, the Federal Government no longer endorses DES for secure communications. The most recently endorsed algorithm is AES. All Federal agency communications systems implementing encryption must use AES. To best ensure interoperability between Federal, state, and local responders, it is recommended that state and local agencies also transition to AES. An encryption implementation in any new P25 system should use AES.
The following links define the AES and DES algorithms and their use, a standard key fill device to manually load encryption keys into P25 radios, and a standard OTAR procedure to automatically rekey P25 radios: