Public network kuberntes cluster

Hi all,

I’m interesting to setup Kubernetes cluster on which all the workers and masters are Linux machines with public IP addresses without any firewall in front of them. I wasn’t able to find anywhere in the documentation that this should not be the case, so I want to know what are the risks and what should be considered in order to protect such cluster.

Could you point me to the articles saying running such cluster is not good idea, despite this one: Control Plane-Node Communication | Kubernetes

Thank you in advance!