2 min. read

What are Container Images and Registries?

Containers are a fundamental building block of modern software. As an isolated environment where entire applications or components can run, they support scalable, agile, and cloud-native development. Ensuring that containerized applications can run correctly, consistently, and securely requires container images, repositories, and registries.

What is a Container Image?

A container image is unchangeable and static. It includes all executable code, system libraries, and components needed to run an isolated process on IT infrastructure. The core component of any containerized architecture is the container image.

Think of container images as templates. The beauty of immutable container images is that they multiply and scale up as workloads increase. This ability offers developers the flexibility and portability to create or update new applications quickly.

What is a Container Repository?

The container repository is where container images and related assets are stored, typically controlling how images and assets are accessed. A container repository stores, manages, and shares container images. A container registry holds the official information on each asset as a collection of repositories.

What is a Container Image Registry?

A container image registry is a server-side application that stores container images, API paths, and access control rules. While Docker Hub is the most popular registry service, others include Amazon ECR and Azure. By connecting directly to container orchestration platforms like Docker and Kubernetes, registries make sharing, managing, and deploying container images seamless.

Public and Private Container Image Registries

There are two types of container image registries, public and private. Public registries tend to be used by small, nimble teams. However, managing complex security issues like patching, privacy, or access control require a private registry. Most cloud service providers—like Google, AWS, and Microsoft—offer private container image registries with additional security and privacy features.

When deciding on a container image registry, consider the type of artifacts that need storage in addition to images. Ensure that the container registry can support the types of files needed beyond container images, like Java, Python, or Node.js. Lastly, understand the additional security features available, including vulnerability scanning, access controls, and runtime security tools.

Create and Secure the Building Blocks of Containerized Apps

Working in a containerized environment requires a deep understanding of container images, repositories, and registries. With the appropriate tool, DevOps teams can maximize output in a standardized, repeatable, and agile way.

Container Security Starts with Panoptica

Cisco’s Emerging Technologies and Incubation (ET&I) team is paving the way with “DevOps-friendly” cloud-native security solutions that fundamentally simplify conventional offerings. Our Panoptica solution simplifies cloud-native application security, making it easy to embed into the software development lifecycle. Panoptica protects the full application stack from code to runtime by scanning for security vulnerabilities in the cloud infrastructure, microservices (Containers or Serverless), the software bill of materials, and the interconnecting APIs. And best of all, it integrates with the tools that your application development and SecOps teams are already using. Try Panoptica for free!