What is CaaS? 

Containers-as-a-Service (CaaS) is a cloud service that helps manage and deploy apps using container-based abstraction. CaaS can be deployed on-premises or in a cloud.

 Containers as a service (CaaS) is a cloud service that allows software developers and IT departments to upload, organize, run, scale, manage and stop containers by using container-based virtualization. A CaaS provider will commonly provide a framework which allows users to make use of the service.

 Google Container Engine(GKE), AWS (ECS), Azure (ACS) and Pivotal (PKS) are some examples of CaaS.

Containers-as-a-service (CaaS) is a category of cloud services where the service provider offers customers the ability to manage and deploy containerized application and clusters. CaaS is sometimes viewed as a special sub-type of the Infrastructure-as-a-service (IaaS) cloud service delivery model, but where the main commodity is containers rather than physical hardware and virtual machines.

Containers essentially function as an alternative to the traditional virtualization approach, where instead of virtualizing the hardware stack using virtual machines, containers virtualize at the level of the operating system. As a result, containers run far more efficiently than virtual machines. They use fewer resources and a fraction of the memory as compared to virtual machines that need to boot an entire OS each time they are initialized.

Within the Container-as-a-Service (CaaS) layer, VMs with VMware Photon OS as the guest OS are used as container hosts to provision Tanzu Kubernetes clusters. The container hosts that host the CNFs are commonly called Worker Node VMs or Worker Nodes