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ESK Announcement

M/A-COM Introduces EDACS Security Key (ESK) for Enhanced Radio System Security

Feature Provides Additional Protection to Restrict Programming, Eavesdropping and Unauthorized Transmission

M/A-COM, Inc. a unit of Tyco Electronics and a leading manufacturer of critical radio systems deployed around the world, today announced availability of the Enhanced Digital Access Communications System (EDACS) Security Key (ESK) to provide heightened security on EDACS and ProVoice radio systems. This new feature provides additional protection against eavesdropping and unauthorized transmissions on critical communications systems.

“Security is a key part of any critical communications system and it is a feature that can’t be overlooked," said Dennis Maddox, Manager of Systems and Infrastructure, M/A-COM. “Any security breach on a system compromises its effectiveness and that of the public safety professionals that rely on it. EDACS ESK meets that security need by allowing users to define a security code that limits access to the system."

Using EDACS ESK, each customer is able to define a unique security code for radio products and site equipment. In the event that the codes do not match, calls will not be received or sent between the two.

Interoperability and Compatibility

In emergency situations that require immediate interoperability, the ESK function can be temporarily disabled by the Communications System Director (CSD) to allow communications with EDACS radios that do not support ESK or have a different ESK stored.

Setting Authorization

The ESK security code is set by the system administrator and stored on a “smart card." The administrator can set two levels of authorization – Administrator, which allows the user to read/write radio personalities and interface with the Communications Systems Director (CSD), and User, which only allows radio personality read/write. Each security code is loaded into the radio equipment using the radio PC ProGrammer software.

All radios within an Integrated Multisite and Console Controller (IMC) region must have the ESK feature enabled with the correct programming in order to be utilized in that region. Once the CSD activates the ESK feature, any radios with incorrect programming are not able to receive or transmit calls.

The EDACS ESK feature is compatible with the following products:

  • Portables – LPE-200, M-RK, Jaguar, P7100, P7200
  • Mobiles – EDACS 500M, Orion, Jaguar, M7100
  • Site equipment – SitePro/Site Interface Module (SIM) and GETC/Site Controller
  • Network equipment – Communications System Director (CSD)

How does ESK work?

For those of you that are not familiar with the EDACS control channel, it is broken down into a number of frames. Each frame is preceded by a specific command word, which identifies to the receiver what the purpose of the frame is. With EDACS system key, this command word has been XOR'd with a specific 8 bit value.

ESK Frame
0101110101001100 000100000001     5D4c 101
|      |   |   | |     |    |
|      |   |   | |     |----|---- System ID                (normal)   
|      |   |---|-|----------|---- Data Channel LCN (9-12)  (normal)
|      ||-|----|-|----------|---- Status Bits              (normal)
********-------|-|----------|---- Command Word (1-8)       (XOR)
|              | |          |
|----msg 1a----| |--msg 1b--|     ESK FRAME Site 01 LCN #12
1234567890123456 123456789012 

Thus, reversing the simple XOR to the expected value for common command words results in a value of "A0", which is the value that the command words are XOR'd with.

Monitoring ESK Systems

There is an ESK enabled version of Etrunker that allows you to track and monitor analog talkgroups on ESK systems. You can download it here:

If you want to track ProVoice Talkgroups using the ESK Version of Etrunker, see the Digital Voice Conversion Method process.

Another option is using the GRE PSR-500/600 scanner which will track ESK enabled systems (However this will not work on systems that use extended addressing) and will allow you to listen to analog talkgroups on those systems. In addition, the Uniden BCD396T and BCD996T will track ESK, as long as version 3.01 firmware (or better) is installed. The recently released Uniden BCD396XT, BCD996xt, and BCD346XT also have this ability to monitor analog talkgroups on an ESK enabled system.

The Uniden BCD436/536 mobile and Base scanners will monitor both analog and digital talkgroups on an ESK enabled system after a $50 Uniden "ProVoice" uprade has been purchased and unlocked within the radio.

EDACS Systems that have ESK installed

  • Cecil County MD (active)
  • Denver Public Safety (active)
  • DFW Airport Public Safety (active)
  • El Paso/El Paso County, Texas (unknown status)
  • Florida Statewide Law Enforcement Radio System (SLERS)(active)
  • Lakewood (Colorado) (active)
  • Rockingham County / Harrisonburg City Public Safety (Virginia) (active)
  • San Antonio/Bexar County, Texas (active)
  • Vancouver BC Canada Emergency Communications (active)

See also