Containerization is still evolving, but the number of organizations adopting containerization techniques has gone up in recent times. In addition to Docker, Microsoft has already invested in Windows containers. While many organizations are aggressively adopting Docker and other container technologies, the downside of these techniques are still the size of the containers and security concerns. Container portability and standardization is another challenge.
Currently, the Docker images are, in general, heavy. In an elastic-automated environment, where containers are created and destroyed quite frequently, size is still an issue. A larger size indicates more code, and more code means they are more prone for security vulnerabilities.
The future is definitely in small-footprint containers. Docker is working on unikernels, a lightweight kernel or cloud operating system that can run Docker even on low-powered IoT devices. Unikernels are not full-fledged operating systems...