What’s CaaS? Containers as a Service Explained

Just a few years ago, only about 20% of organizations were using container management tools. That will soon change, though: Gartner predicts that, by 2027, over 90% of major global organizations will use container management tools for their hybrid cloud environments.

If this trend continues as predicted, containers will have a bigger impact on organizations to move to technologies like CaaS. 

What is containers as a service?

Container as a Service (CaaS) is a type of cloud service to deploy, manage, and scale containerized applications. Some popular CaaS examples are AWS EKS, Google GKE, or Azure Kubernetes Service.

If developers want to package applications into containers and deploy them on the cloud, then CaaS is a solution they should look at. CaaS platforms are platform-agnostic, allowing containers to run across various cloud environments — public, private, and hybrid.

As a cloud service model, CaaS is positioned between IaaS and PaaS. It offers the right balance of control and simplicity, supporting agile development.

What is the role of containers?

A container is a lightweight package that includes everything an application needs to run — its code, libraries, dependencies, etc. Containers help applications to run consistently across different environments.

Unlike traditional virtual machines (VMs), which include a lot of unnecessary files, containers only carry the essential metrics needed to run an application. This makes them faster to start and less demanding on resources.

Containers also work well with the latest application designs, like microservices, where each feature runs separately and can be easily scaled or updated. 

How CaaS differs from traditional methods

Before CaaS, deploying applications was much more complex. It relied on traditional methods like virtual machines or physical servers.

Virtual machines were helpful because they let you run multiple environments on the same hardware, but there was a big flaw: each VM needed its own operating system. This made them heavy on resources, requiring a lot of memory and CPU power to function. Another issue was how slow VMs were to start up. Since they had to load an entire operating system every time, the process took much longer compared to modern containers — which share the host OS and are much lighter.

Besides the VM startup issues, developers often struggled to replicate production environments during testing. That means traditional setups didn’t offer the consistency and portability that containers offer when replicating environments like QA or staging. This resulted in more bugs and issues being identified too late, only when moving applications from one environment to another.

CaaS changed this process by introducing containers. These containers bundle applications with only the files and dependencies they need to run. Unlike VMs, containers share the host operating system so they are much lighter and faster to start. This means businesses can run hundreds of containers on the same resources.

CaaS platforms also bring in tools like Kubernetes to handle container orchestration, automating tasks like:

• Scaling
• Monitoring
• Managing container lifecycles

This takes away much of the manual work involved in traditional methods. Further, these technologies help to speed up development and move the product releases consistently across dev, stage, and production environments.

(Related reading: how to monitor Kubernetes.)

Benefits and importances of CaaS

Containers as a service simply makes life easier for development teams. It combines the benefits of container management systems and cloud services:

• Providing built-in orchestration tools, so you don’t have to manage containers manually.
• Offering benefits common to cloud services, such as scalability on demand, a pay-as-you-go model without the need to invest in infrastructure, and portability because it is platform-agnostic and does not rely on the underlying infrastructure.

With that background, let’s move into the nitty-gritty details of CaaS.

How does CaaS work?

CaaS creates an abstraction layer that separates containers from the underlying infrastructure. It uses containers as the fundamental blocks. No need to rely on virtual machines or physical servers.

The service provider manages the complexity of hardware, operating systems, and Kubernetes nodes behind the scenes. It provides users with web portals, APIs, or command-line tools to upload, deploy, and manage their container workloads.

At the core of CaaS, there is an orchestration engine that takes care of all the coordinating work among the active containers. This engine automates important tasks like scaling and load balancing to run everything smoothly. Whether you’re using serverless platforms like Google Cloud Run or managed Kubernetes services like Amazon EKS, the orchestration engine helps to keep your operations more reliable.

Key components in CaaS architecture

The CaaS architecture is designed by breaking it down into distinct layers. Here’s a look at the key components of CaaS architecture.

Infrastructure layer

This is the foundation of the CaaS platform, which provides the physical or virtual resources needed to run containers, such as computing power, storage, and networking capabilities. CaaS providers manage these resources entirely.

Container orchestration layer

This layer handles the lifecycle management of containers. It uses orchestration tools like Kubernetes, Docker Swarm, or Apache Mesos to automate tasks such as:

• Provisioning
• Scaling
• Scheduling

Containerization layer

The containerization layer is designed to package applications and their dependencies into lightweight, portable containers. Tools like Docker are commonly used here to create containers, which can then be stored and shared through registries like Docker Hub.

This layer is important for achieving portability — and that portability is what makes containers so valuable.

Platform services layer

This layer provides additional services that support containerized applications, such as load balancing, service discovery, and logging. These services can be accessed through APIs or web interfaces.

Application layer

At the top of the architecture, you can find the application layer. This contains the containerized applications deployed across the platform.

Developers create these applications using various programming languages and frameworks. Then package them into containers to run on the CaaS platform. This layer represents the final working output of the entire architecture.

Primary features in containers as a service 

Let’s have a look at key features a CaaS platform should have. 

• Containerization: Packages applications and their dependencies into portable containers for scalability and agility.
• Container orchestration: Automates deployment, scaling, and lifecycle management of containers using tools like Kubernetes.
• Networking: Provides smooth communication between containers with virtual networks and software-defined networking (SDN).
• Platform configuration: Provides APIs and interfaces for defining resource requirements, networking, and environment variables.
• Security and access control: Includes features like role-based access control (RBAC) and vulnerability scanning for secure operations.
• Integration with other services: Supports integration with cloud-native tools, CI/CD pipelines, and DevOps workflows.
• Content distribution: Enables content dissemination across channels with REST-based APIs.
• Content management: Offers triggers for content updates and workflows for efficient administration.
• Cloud hosting: Provides universal access to content repositories hosted in the cloud.
• Structured query support: Returns content in structured formats via simple queries.

How CaaS compares with IaaS and PaaS

CaaS, IaaS, and PaaS are three essential cloud service models, but how do they differ? The following table summarizes the differences.

CaaS security, and where it falls short

CaaS platforms are built to provide high security and safer container management. They take away huge burden from enterprises by taking responsibility for securing the underlying infrastructure. This foundational security approach helps containers to operate in a protected environment — a plus for organizations concerned about security. 

However, the cloud operates on a shared responsibility model. Organizations still have the responsibility to secure their data and applications. They should adhere to strict security practices, such as:

• Avoiding container images with vulnerabilities.
• Enforcing least privilege access.

Since containers share the same kernel as the host operating system, any compromise to the kernel can potentially impact all containers running on it.

This risk becomes even greater when containers are deployed in the cloud via CaaS because multiple containers often share the same underlying infrastructure. If one container is compromised, it could potentially expose vulnerabilities in all containers in the shared environment.

(Related reading: top application security requirements to use.)

Does CaaS make DevOps more efficient?

CaaS enhances DevOps efficiency by providing a shared platform with a consistent framework for building, testing, and deploying containerized applications. It standardizes processes with predefined tools and services like Kubernetes, Docker Swarm, and APIs, which are useful for container orchestration and management.

Developers can package applications into containers using these standards, QA engineers can test them in identical environments, and DevOps teams can manage deployment, scaling, and monitoring. This approach in CaaS reduces inconsistencies and improves collaboration across teams.

CaaS helps to automate many processes like container deployment, scaling, and lifecycle management. This automation reduces human error and speeds up the product delivery process. Therefore with CaaS practices, DevOps teams can deliver updates faster to the production environment.

The future of CaaS with FaaS and DBaaS on the rise

Looking ahead, CaaS will continue to play a key role in container management. However, it might adapt to work alongside emerging technologies like Function as a Service (FaaS) and Database as a Service (DBaaS). 

While FaaS offers serverless solutions for specific tasks and DBaaS simplifies database management, CaaS provides the foundational layer to manage containerized applications. These models aren’t replacements but complementary methodologies.

In the future, we are likely to see businesses combining them for maximum efficiency. With emerging other technologies CaaS may become more specialized and it will be integrated with other services to meet the growing demand for cloud solutions.