[Danke]

Typically you'd save authenticate for when you get orders over the radio. once again this is a real world deal so you're klicks away from the folks issuing the order and you can't just stroll back over the hill to make sure the person on the other end is who they say they are.

So, you are out on patrol and a message comes across, we've made contact with the enemy and their base is on hill XXX, we need everyone here to support us now and over-run them.

Great idea, you've found the enemy and used the radio to bring your team to bear and make sure they don't escape.

But wait a minute, what if it's someone from the other side who's spent the last hour listening into your call signs and voice procedure? They'll have your whole group haring over the hills for no reason or being sucked into a hasty ambush!

So after you get the message where you need to say "are you serious", you say something like "Bravo Five, Authenticate". They will respond with a one time code word that shows the message is coming from who they say they are, and not someone jerking with you. Voice procedure can be somewhat fluid but you do want to keep it short and sweet, the reply would be like "Bravo One I authenticate Pumpkin".

This is where you need a designated signaler who'll have those keywords written down and handy. No point in trusting memory at that point. The signaler at the other end in HQ will have a similar list for each group out in action and will strike out each as it's used since as soon as it's been said over the air it's no good any more.