Encryption for network security is a non-trivial matter, particularly in complex environments. Traefik and Let’s Encrypt can make the process of securing Kubernetes clusters simpler, speedier, and more resilient.
External reverse proxy and load balancing software like Traefik offer networking features and control that Docker Swarm cannot provide on its own.
When adopting microservices, Kubernetes alone may not be enough to handle more complex networking challenges that arise. This is the job of a service mesh.
Kubernetes is often used to manage external-facing applications, so the need for protecting applications from harmful external traffic is nearly universal.