Traefik is a cloud-native reverse proxy/load balancer that makes deploying micro-services easy, it automatically discovers the right configuration for the services that are going to deploy, which makes Traefik more popular, besides its many features.
Docker Swarm is native clustering for Docker. It turns a pool of Docker hosts into a single, virtual host. We continue to run the Docker commands we’re used to, but now they are executed on a cluster by a swarm manager. The machines in a swarm can be physical or virtual. After joining a swarm, they are referred to as nodes.