WTE TReX-460, User Manual

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TReX User Manual v15.30 Firmware
RF Security
The TReX allows for AES 256-bit encryption to be used for transmitted data. Same content
messages will change with each transmission due to an embedded unique timestamp.
A default key is loaded into the TReX, common to all units. This is for evaluation purposes
only, and should be changed before the system is considered to be secure. For evaluation,
steps 1 and 2 below can be omitted.
In order to create a secure radio link:
1. Generate a random 256 bit key. Use a key generator or use an online web service such
as https://www.allkeysgenerator.com/Random/Security-Encryption-Key-
Generator.aspx . The key must be hexadecimal in format and will be 64 characters long.
This key must be used on all devices in the same system, and must be changed if the
key has become publicly known.
2. Use the command *RF_KEY to enter the key, either using a terminal or adding the
command to a configuration file.
Note: Reading back the key with *RF_KEY? will only display the first 4 characters of
the key. All other configuration items can be set through the menu if required.
3. Go to the RF->ENCRYPTION menu.
4. Select the desired encryption method and options.
5. Ensure the
LOCAL ID is unique to the system – every transmitting TReX must have a
different LOCAL ID . This ID is the same as TELEMETRY->LOCAL ID.
AES Encryption is only applied when using the transport options POCSAG_A or WTE_EN .
WTE_EN must be used when 8 bit characters are being transmitted, such as when the point to
point serial link is used. WTE_EN encrypted messages have the ability to be 20% shorter than
the POCSAG_A transport method. POCSAG_A can be used in most cases when a standard
format is required, or encryption for nationwide paging is desired. Both transport methods
include forward error correction for high receiver sensitivity.
© WTE Limited, 2022 – Christchurch New Zealand
Page 239 of 302