Without PaaS, Docker is just a bunch of containers

Docker containers deliver plenty of advantages, but they need an enterprise umbrella, says a cloud expert.

Docker containers may be the greatest thing since sliced bread, but they still an extra something to work well within enterprises. This is where Platform as a Service comes in.

Photo: IBM Media Relations

That's the word from Bernard Golden, vice president of strategy for ActiveState, who observes that container technology is much more efficient and delivers greater benefits than standard virtualization. In a recent webcast hosted by InformationWeek, he pointed out that containers share a common operating system, and where appropriate, binaries and libraries. This assures even greater hardware and systems utilization than virtualization and cloud.

(A great discussion on the differences between virtualization approaches and Docker containers is posted on the StackOverflow site. The elevator speech is that a container approach is much "lighter" than a standard virtualization approach, since it involves greater sharing of underlying resources, such as operating systems.)

However, Docker containers do not deliver additional value to IT, Golden said. "A developer who builds his or her own container gets the benefits of it, but doesn't get surrounding capabilities," Golden pointed out. The issue is that Docker containers won't address the challenges of managing a complex topology, requiring management of multiple application environments, ensuring high availability, providing quality and assurance, and monitoring performance. "If you really want to deploy Docker to a hybrid environment, you really need a surround set of tools and frameworks so you can get all the benefits of Docker containers," he said. This is why Platform as a Service is needed.

Having a PaaS infrastructure provides for integration between services, such as internal database services and external cloud services. Docker containers require a coordinated execution environment, Golden pointed out. "Developers, even if they start with a Docker container, they're still left with a tremendous amount of assembly," he said. PaaS also provides for the operations side as well, enabling scaling and distribution of container-based applications and services as needed.

The bottom line is container technology, while delivering greatly enhanced applications, still needs an enterprise-scale structure. PaaS offers that, Golden said.