Encrypted Radio Communications with DMR Privacy Modes

Encrypted Radio Communications with DMR Privacy Modes

In a previous article ‘2-Way Radios & Communicating in Protective Services‘ we discussed radio options and other communicating techniques. One of the primary issues most security practitioners face when communicating with 2-way radios is the lack of secure communication. This article is meant to discuss the reasonable options available to us which afford much more secure communication.

The advent of Digital Mobile Radio (DMR) has brought on many advantages over analog radio. Although they are more expensive and require more knowledge/training to operate and program than analog systems, the advantages are far superior. DMR signals are much clearer, offering audio which is easier to understand, especially at longer distances where analog signals tend to fade. DMRs also transmit ‘packets’ of data, allowing for other information such as text messages, gps location and/or other information to be sent along with the audio.

Perhaps the biggest advantage to security practitioners and protective service professionals offered by DMR is the ability to add privacy modes, or ‘encryption,’ to the radio. Additionally, DMR radios can still communicate to analog radios if in analog mode, so there is no real downside (other than price) with a DMR radio. Read more on DMR Basics

Most DMR options today offer two privacy methods while programming the radio via software. They are ‘basic’ and ‘enhanced.’ The operability of the modes does depend on the brand, so ensure your radio is MotoTRBO compatible with both Tier 1 and Tier 2, in addition to having two time slots available. (check the specifications of your intended purchase) A third option is available, which offers top-level encryption but requires a license and specific software: AES 256

MotoTRBO is from Motorola, so you can certainly purchase a slimline, excellent SL7550 which I have or a XPR7550 for $750 each and get excellent performance (and you will still need the $300 software and $100 programming cable). If you research other options, such as the TYT MD-390 which I also have, purchased for $120 including programming cable and software, which is also free to download. However the choice is yours depending on your budget, task, threat and environment.

Both privacy types offered with DMR radio required the listener to have the exact same key and code as the other radios they desire to communicate with. The difference between basic and encryption is the level of security offered. Note: these are also technically not ‘encryption’ but rather a scrambling and unscrambling of your transmission as per an assigned ‘key code.’

Basic privacy is simply a choice of a key between 1-255 assigned to the TX/RX frequency which must match. This is simply a selected option without any customization, hence if a listener was dedicated they can simply scan all 255 keys and potentially find the one you are using. Enhanced privacy offers a 40-bit encryption in which the user inputs a custom key, meaning you select any assignment of letters and numbers such as ‘A7H9NBV512ABC8’, along with a key name and number slot assignment which must all match. This is much more secure than basic privacy as any potential listener would have a very difficult time figuring out your custom key.

DMR Radio Demo

*Analog systems typically used ‘frequency hopping’ in which all radios must have the same hop set and on the exact same ‘time’ in order to communicate. This caused many programming issues which the new DMR system does not have considering the radios only need the key.

‘KM4YYW is clear.’

See this programming video for more information: Programming Enhanced Privacy


Joseph M. LaSorsa, CPP® is currently employed as a senior partner managing and conducting: Protective Operations Training Courses, Executive Protection & Bodyguard Services, Risk Management Consultations & Seminars, Workplace Violence Prevention Seminars & Intervention Services, Security Consultations & Seminars, Private Investigations and Technical Surveillance Counter-Measures with LaSorsa & Associates – an International Protection, Investigations & Consulting Firm.

Protective Security Group

Leave a Reply