Practice and Training Resources

MsgAuth has been updated, and we’re still working on updating this page. Please check back soon.

Nothing beats real-world, hands-on experience, so now that you’ve got MsgAuth downloaded and ready to go, here’s one way to get that experience. By the way, the screen captures here are using the dark theme, which is set by changing the first line of the msgauth.cfg file to “dark” – the default option is “light”.

Let’s start with a simple example. Station KN4AM is sending a message to QST – THE CHAIR IS AGAINST THE WALL (Yes, we’re using movie quotes for our examples)

So, it’s pretty simple – just enter the source and the target (both are being verified by the program), enter the message, select the agreed upon codeplug, and click “Sign”. The formatted signed message is automatically saved to your clipboard, ready to be pasted into whatever program you’re using – or ready for you to read in a voice contact.

To validate the message, enter the target and source stations, the message, the CRC, and select the codeplug both sending and receiving stations have agreed upon. IMPORTANT – do not include anything in the Message field other than the actual message; the program will add the target and source station. Click the Validate button to see the result.

That was our simple example. Are you ready to dig deeper? Sorry, that’s all there is. It’s really that simple. Now it’s your turn. Following are some sample messages. Most are valid, but two are not. Go through the messages and find out which are real and which are fake.

All practice exercises and examples on this site use the following as a practice codeplug:

-99-98-97-96-95+94+93+92+91+90

JOHN HAS A LONG MUSTACHE
KN4AM: QST JOHN HAS A LONG MUSTACHE FEM

THE CHAIR IS AGAINST THE WALL
KN4AM: QST THE CHAIR IS AGAINST THE WALL A2K

WE’RE NOT IN KANSAS ANYMORE
KN4AM: QST WE’RE NOT IN KANSAS ANYMORE RCU

AS YOU WISH
KN4AM: QST AS YOU WISH X3O

HERE’S LOOKING AT YOU, KID
KN4AM: QST HERE’S LOOKING AT YOU, KID 0AB

GO AHEAD, MAKE MY DAY
KN4AM: QST GO AHEAD, MAKE MY DAY VWR

MAY THE FORCE BE WITH YOU
KN4AM: QST MAY THE FORCE BE WITH YOU 16P

FASTEN YOUR SEATBELTS
KN4AM: QST FASTEN YOUR SEATBELTS ZWJ

I LOVE THE SMELL OF NAPALM IN THE MORNING
KN4AM: QST I LOVE THE SMELL OF NAPALM IN THE MORNING UJL

BOND. JAMES BOND. —– ⚑ Note the periods
KN4AM: QST BOND. JAMES BOND. 92Q

THERE’S NO PLACE LIKE HOME
KN4AM: QST THERE’S NO PLACE LIKE HOME Q71

ROUND UP THE USUAL SUSPECTS
KN4AM: QST ROUND UP THE USUAL SUSPECTS UX3

Authentication using Voice Modes

What if you need authentication, but you’re using voice and not digital? What if your local comms with those in your immediate area are over CB? Maybe you are confident that you recognize the voices of those you trust, but what if conditions are poor and you don’t have a clear signal? What if you are using SSB CB with it’s voice distortion? MsgAuth can solve that problem.

Let’s use our “The chair is against the wall” example. Everything is done the same, and the results are the same. It’s just spoken over the air instead of typed in a digital format.

“But what about spoofing? The bad guys will be able to hear that and can then repeat that authentication.” That’s true – IF you use the exact same phrase. One solution is to simply include the time (just the minutes should be sufficient), so that at 11:25, you would use “The chair is against the wall 25”; then at 11:45, it would be “The chair is against the wall 45”. You’ll have completely different CRC results, so the new phrase will not authenticate using the old CRC. You can, of course, use ANY phrase and not even bother with adding the time. Current versions of MsgAuth include a built-in date code that will add it to your string. In this example, it is #BLOT, followed two minutes later by #BLOU.

KN4AM: QST THE CHAIR IS AGAINST THE WALL #BLOT ULC
KN4AM: QST THE CHAIR IS AGAINST THE WALL #BLOU HGM

The key here is that any change in the message, the source station, or the target station is going to change the CRC, so you have a lot of flexibility in how to use it.

Quiet Authentication
You don’t have to use something that sounds like you are sending an authentication, and the CRC can be separated from the message to further hide it. For example, you might agree that your group is going to use car parts for authentication. Over the air, you might say, “I need a radiator, and the part number is 18725 dash DI4.”

This is what the target station gets: KN4AM: QST RADIATOR DI4

There are all sorts of ways to use this, either openly or hidden. Use your imagination, and you’ll come up with all sorts of creative ways that work for your group.

This section is a work in process – the radio-based exercises and practice files are still being created as of FEB 7. They should be ready soon, so please check back in a few days.

Stations set up for practice

These stations are ready for you to request and download MCForms, and send and receive traffic that includes message authentication using MsgAuth. All practice exercises for MsgAuth use the following as a practice codeplug:

-99-98-97-96-95+94+93+92+91+90

The JS8Spotter Expect Statements:
PRAC – General practice information available from this station
PMA01 (02, 03, 04…) – Practice MsgAuth files using the Practice Codeplug. Some will authenticate – some will not. Your task is to find out which are valid.
PMA01A (02A, 03A, 04A…) – Answer statements. “V” = Valid sender, “N” = Not Valid sender

How to use the Practice Stations for MsgAuth

1. Use JS8Call to check to see if the station is available by sending, for example: KN4AM SNR?
2. Use JS8Spotter to request a list of MsgAuth practice messages and other practice resources by sending, for example: KN4AM E? PRAC
3. You will receive a list of practice traffic to process and determine whether it is valid or not valid.
4. Once you’ve checked using MsgAuth, then request the answer to see if you got it right.