How to protect all dockers with authentication?

Hi, I’m learning to use docker. I have several dockers already running.

I’d like to find a way to protect my dockers with an authentication system, a docker or other way like.

My guess would be to put my dockers services in one docker wich runs an authentication system. there is any tutorial I can learn how to do this ? or do you have any suggestion ? and what kind of authentication would you suggest to me to use ?

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thx.