Compiled by Kiran Kumar, Business analyst at Powerup Cloud Technologies
Contributor Agnel Bankien, Head – Marketing at Powerup Cloud Technologies
Container-as-a-service (CaaS) is a business model offered by cloud service providers that facilitates the software developers in organizing, running, managing, and deploying containers by using container-based virtualization.
Containers are responsible for packaging applications and their dependencies all together in a compact format that can be version controlled, are scalable and can be replicated across teams and clusters as and when required.
By segregating the infrastructure and application components of a system, containers can accommodate themselves between multi-cloud and hybrid environments without altering the code, thus posing as a significant layer between the IaaS and PaaS platforms of cloud computing.
Implementing CaaS has advantages like rapid delivery and deployment of new application containers, operational simplicity, scalability, cost-effectiveness, increased productivity, automated testing and platform independence to list a few. CaaS markets are growing rapidly with enterprises across all domains adapting to container technology.
1. What are Containers?
2. What is Container-as-a-Service (CaaS)?
3. How CaaS differs from other cloud models?
3.1 How CaaS works?
4. Who should use CaaS?
4.1 Type of companies
4.2 Type of Workloads
4.3 Type of Use Cases
5. How CaaS has impacted the cloud market?
6. Benefits and drawbacks
What are Containers?
Containers are a set of software capable of bundling application code along with its dependencies, which can be run on traditional IT setups or cloud. Dependencies include all necessary executable files or programs, code, runtime, system libraries and configuration files.
Since containers are efficient in running application files without exhausting a great deal of resources, users see it as an approach to operating system virtualization.
56% of the organizations that polled for the 2020 edition of “The State of Enterprise Open Source” report said they expected their use of containers to increase in the next 12 months.
Containers leverage operating system features to control as well as isolate the amount of CPU, memory and disk being used while running only those files that an application needs to run unlike virtual machines that end up running additional files and services.
Containerized environment can thus optimize a system to run several hundreds of containers as against 5 or 6 virtual machines that would typically run on a traditional virtualization approach.
What is Container-as-a-Service (CaaS)?
Container as a service (CaaS) is an automated cloud based service that enables users to host and deploy highly secure and scalable containers, applications and clusters via on-premise data centers or cloud.
CaaS acts as a significant bridge between the IaaS and PaaS layers of cloud computing services often regarded as a sub-division of IaaS delivery model.
By segregating the infrastructure and application components of a system, containers can accommodate themselves between multi-cloud and hybrid environments without altering the code.
Gartner says that 81 % of companies that have already adopted public cloud are working with two or more cloud providers.
CaaS is considered the most flexible and best-fit framework in providing tools to cater to the entire application lifecycle while also being capable of operating in any language and under any OS and infrastructure benefitting the organization’s software development and operations teams.
It helps organizations attain product excellence, speedy deployment, agility and application portability while assuring improved application delivery and stellar customer service.
How it differs from other cloud models
With the evolution of cloud computing, several “ as a service” offerings have actualized in enhancing core business operations. The three traditional service models securing maximum prominence in the recent past are:
Infrastructure-as-a-Service (IaaS) that provides virtual hardware, storage and network capacity, Platform-as-a-Service (PaaS) catering to the entire software development lifecycle and Software-as-a-Service (SaaS) that deals completely with running application software on cloud.
The first six months of 2020 saw a 22% rise in organizations that have containerized more than half of their applications.
Container-as-a-Service can be positioned between the IaaS and PaaS layers of cloud computing models where using container technology, CaaS is able to create a virtualized abstract layer that captures applications and files from the elementary system and directs it on any container based platform for operations.
Meaning, CaaS utilizes native functions of an OS to isolate and virtualize individual processes within the same operating system unlike IaaS model, where the user is responsible for installing and maintaining the virtual hardware and operating systems. Thus, CaaS manages the software application lifecycle similar to what IaaS and PaaS do but with a slight difference.
Additionally, in traditional cloud systems, software developers are heavily dependent on technologies provided by the cloud vendor.
For instance, a developer who uses PaaS to test applications needs to load his own code onto the cloud while all technical requirements for the build process as well as managing and deploying applications are taken care of by the PaaS platform. However, Container-as-a-Service, provides users with a relatively independent programming platform and framework, where applications confined in containers can be scaled over diverse infrastructures, regardless of their technical requirements making it less reliant on the PaaS model.
How CaaS works
CaaS platform is a comprehensive container management environment comprising orchestration tools, image repositories, cluster management software, service discovery, storage and network plug-ins that enable IT and DevOps to effortlessly deploy, manage and scale container based applications and services.
The interaction with the cloud-based container environment is either through the graphical user interface (GUI) or API calls and the provider controls which container technologies should be made available to users.
Docker Swarm, Kubernetes, and Mesosphere DC/OS are the three most dominating orchestration tools in the market. With such built-in orchestration engines, CaaS solutions enable automated provisioning, scaling, and administration of container applications on distributed IT infrastructures. Moreover, cluster management features allow applications to run as clusters of containers that can integrate and work collaboratively as a single system.
Containers are capable of overcoming problems arising from having multiple environments with disparate configurations as it enables development teams to use the same image that gets deployed to production. Also, since containers are meant to be recreated whenever needed, it is considered best to centralize logs. CaaS facilitates aggregation and standardization of logs along with monitoring capacities.
All leading IaaS providers like Google, AWS, Microsoft Azure, Red Hat, Docker Cloud and OpenShift have CaaS solutions built on top of their IaaS platforms whose underlying orchestration solutions help automate provisioning, clustering and load balancing. Some of these providers also offer PaaS solutions that allow developers to build their codes before deploying to CaaS.
Who should use CaaS?
A recent survey by Gartner predicts that by 2023, 70% of organizations will be running three or more containerized applications in production where containers, Kubernetes and microservices would emerge as leading drivers of IT digitization.
With everyone favoring DevOps these days, numerous large IT organizations are attaining container capabilities by purchasing smaller startups.
According to the Datadog report, the move to Docker is actually being led by larger companies (with 500 or more hosts), rather than smaller startups which supports the fact that Docker use by enterprise-scale organizations is greater than average for all businesses as it is considered relatively simple to deploy.
For example, the scale of deployment reported at a SaaS company was as high as 15,000 containers per day where the process of container deployment was easier and faster making the present-day transition achievable.
Type of workloads
Most infrastructures are complex and host a diverse set of workloads. While virtual machines virtualize physical hardware keeping an efficient isolation mechanism, containers virtualize the operating system provisioning very little for workload isolation. Hence it is important for enterprises to determine the percentage and portions of infrastructure that are best suited for containerization.
Containers, regardless of their popularity, would continue to coexist with virtual machines and servers, as they cannot substitute them entirely.
If there are workloads that need to scale significantly or applications that need prompt and swift updates, deploying new container images could be a reliable and authentic solution as well.
High number of workloads, understanding how open an organization’s container solutions are and availability of container expertise teams are a few more factors that decide how much to containerize.
Type of use cases
Organizations are known to use containers to either lift or shift existing applications into modern cloud architectures, which provide restricted benefits of operating system virtualization or they restructure existing applications for containers offering full-fledged advantage of container-based application architectures.
Similar to refactoring, developing new native applications also provide full benefits of containers.
Moreover, distributed applications and microservices can be conveniently isolated, deployed and scaled using independent container blocks, containers can provide DevOps support to streamline integration and deployment (CI/CD) as well as allow smooth implementation of repetitive processes that can run in the background.
One of LTI Powerup’s distinguished clients, a large ecommerce start-up, was running all their applications on AWS multi-container environment. Due to this set up, the existing environment was unable to scale for individual services, cost of running their micro-services were increasing and deployment of one service was affecting other services as well. The DevOps team at LTI Powerup proposed and implemented the Kubernetes cluster from scratch to help the client overcome all the above stated issues.
How CaaS has impacted the cloud market?
The Containers as a Service (CaaS) market is expected to grow at a Compound Annual Growth Rate (CAGR) of 35% for the period 2020 to 2025.
The CaaS market has been segregated based on deployment models, service types, size of the enterprise, end user application and geographical regions.
The demand for CaaS is navigated by factors like rapid delivery and deployment of new application containers, operational simplicity, benefits of cost-effectiveness, increased productivity, automated testing, platform independence, reduced shipment time due to hosted applications and increasing popularity of microservices.
As per market studies, the security and network capability segments are expected to grow at the highest CAGR while it is also anticipated that CaaS will provide new business opportunities to small-medium enterprises during the forecast period. Technologies like mobile banking and digital payments are transfiguring the banking industry, especially in emerging countries like India and China where major BFSI companies have already started deploying container application platforms in their systems.
Among the deployment models, the public cloud segment is estimated to continue to hold a significant market share as it offers scalability, reliability, more agility and flexibility to organizations adopting containers.
However, markets foresee data security threats on cloud that may hamper the growth trend, which needs to be strengthened by implementing security and compliance measures with immediate effect.
North America showcased the largest market share in 2017 whereas the Asia Pacific (APAC) region is projected to grow at the highest CAGR by 2022. The increasing use of microservices and the shift of focus from DevOps to serverless architecture are driving the demand for CaaS globally.
Some major influential public cloud vendors providing CaaS are Google Container Engine (GKE), Amazon Elastic Container Service (ECS) , Microsoft Azure kubernetes Service (AKS) followed closely by Docker, to name a few. Google Kubernetes and Docker Swarm are two examples of CaaS orchestration platforms while Docker Hub can be integrated as a registry for Docker images.
CaaS markets have evolved rapidly in the past 3 years and Enterprise clients from all industries are seeing the benefits of CaaS and container technology.
Benefits and drawbacks
- Speedy Development: Containers are definitely the answer to organizations looking at developing an application at a fast pace subject to maintaining scalability and security. Since containers do not need operating systems, it takes only seconds to initialize, replicate or terminate a container leading to speedy development processes, consolidating new features, timely response to defects and enhanced customer experience.
- Easy Deployment: Containers simplify the process of deployment and composition of distributed systems or micro service architectures. To illustrate, if a software system is organized by business domain ownership in microservice architecture, where the service domain can be payments, authentication and shopping cart, each of these services will have its own code base and can be containerized. Therefore, using CaaS, these service containers can be instantly employed to a live system.
- Efficiency: Containerized application tools such as log aggregation and monitoring enable performance efficiency.
- Scalability and High Availability: Built in CaaS functions for auto scaling and orchestration management allows teams to swiftly build high visibility and high availability distributed systems. Besides, it not just builds consistency but also accelerates deployments.
- Cost Effectiveness: As CaaS do not need a separate operating system, it calls for minimal resources, thus significantly controlling engineering operating costs as well as optimally minimizing the DevOps team size.
- Increased Portability: Containers trigger portability that enables end users to accurately launch applications in different environments, such as public or private clouds. Furthermore, it lets incorporation of multiple identical containers within the same cluster in order to scale.
- Business continuity: As containers, to a certain degree, remain isolated from other containers on the same servers, in case of an application malfunction or crash for one container, other containers can continue to run efficiently without experiencing technical issues. Similarly, the shielding that the containers have from each other, doubles as a safety feature, minimizing the risk. If an application is at risk, the effects will not extend to other containers.
However, organizations need to contemplate whether they even need containers before implementing CaaS. To begin with, containerization increases complexity because it introduces components that are not present in the IaaS platform.
Containers are conditional to network layers and interfacing with host systems can hinder operational performances. Constant data storage on containers is a challenge as all the data disappears by default once containers are shut down.
Additionally, container platforms may not be compatible with other container products on the CaaS ecosystem. Lastly, creative GUI apps may not work well as CaaS services were designed to mainly cater to applications that do not need graphics.
CaaS is a powerful modern hosting model, most beneficial to applications that are designed to run as independent microservices. Migration to containers may not necessarily be the best choice for all users as in some cases, traditional virtual machines may serve better. Nevertheless, CaaS, IaaS and PaaS are distinct services with different management models and only organizations can determine how and when CaaS can benefit their operations.