ComSec – What is it and how do I use it?

ComSec - Communications securityWhat does “ComSec” mean?

“ComSec” is the term used meaning communications security. Communications security is a system of protocols that protects your communications from interception and being used against you.


How does ComSec apply to radio signals?

ComSec - Radio communications securityRadio signal interception can be used against you in two primary ways:

  1. If personnel are trained they can use basic radio gear to “triangulate” your position.
  2. Once intercepted, they can use the information in your radio transmission against you. It is called “intelligence gathering” and can be quite effective as a tool.

The dual threat can be used with devastating results. But, there are some methods to defeat both:

  • Use as low a power setting for transmission as possible. That keeps the radio signals from traveling any further than they absolutely have to. The signal can also be reduced by using smaller/shorter antennas.
  • Transmit while moving and never from your area of operations (AO) unless it is an emergency.
  • Transmit for only a very short time. I am talking in terms of seconds, the shorter the better. That will make it more difficult for them to pick up your signal.
  • ComSec communications security coded messagesRandomly change the frequency that you are transmitting on.
  • If you are using a dual-band capable radio like the Baofeng UV-5RA split your radio traffic between both bands.
  • Use different radio operators so the voice doesn’t sound the same.
  • Use coded messages.
  • Substitute letters and numbers (Phonetic Alphabet) for locations. Example: the town of Salem is referred to as “Sierra Tango” meaning “Salem Town”.
  • Use numbers as replacements for words. The most simple would be a two-number code for each letter. Example: “no” would be “1415” But that is easy to figure out. So come up with your own.
  • There are other coding systems but this posting is not an article for that subject. However, one method is Communications-Electronics Operating Instructions (CEOI). You might want to look into it.

Always assume the worst…assume someone is always listening to you and what you are saying. And always assume they can figure out the location that you are transmitting from. You should always act accordingly when circumstances require or demand it.

There is always a cardinal rule, one that should never ever be broken in terms of ComSec. You never, ever use a name…especially a person’s name, first or last; not even a nickname.

Also, understanding all the above means you can turn it around and use it to your advantage. You can give out false or misleading information to misdirect those that might wish to do you harm. If it is a matter of life and death you could always draw them to a location through your radio traffic as well. Then deal with the threat accordingly.

What I am trying to accomplish here is pretty straight forward. I want you to be aware of your radio traffic, safeguard you important information, and don’t say inappropriate or damaging things over the radio. It could be a matter of life and death…yours.

There were posters from WWII that tried to convince people not to talk too much or about the wrong subjects. Still applies today.




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