Understanding The Key Attributes Of Cloud-Native Applications

Cloud-Native apps take advantage of the emerging cloud-based technologies like functions as a service, microservices, containers, Kubernetes, and declarative event-driven APIs. These are the building blocks used to design, construct, deploy, and run modern applications. These technologies are at the core of all automated pipelines for continuous implementation and continuous delivery (CI/CD), which is the foundation for modern Development and Operations — DevOps.

At the heart of the design, Cloud-native applications are these loosely coupled services, which can be viewed as being small snippets of specialized code. They may be called functions or microservice, depending on their characteristics. Either way, they are used to build a specific service. Typically, the ground rule is 1 microservice = 1 purpose = 1 service. This rule ensures service independence and that resources for each service are efficiently provisioned, making the application flexible and adaptable to a cloud architecture.

Key capabilities of cloud-native applications are as follows:

• Microservices-based: Microservice architecture principles require an application to be decomposed into a series of independent services or modules. Each service is independent, isolated with its own data, and supports a single business purpose. In a microservices architecture, the modules communicate with one another via application program interfaces (APIs).
• Container-based: Containers are software constructs that are similar to virtual machines (VM) but without the OS. Instead, a container holds the application source code and all the required dependencies and libraries it needs to run. This makes containers very easy to deploy on any platform as they can be run independent of physical resources on any operating system. Containers keep microservices from interfering with one another and stop anyone from consuming all the host’s shared resources, thereby solving the noisy neighbor problem. However, they also enable multiple instances of the same service, which addresses redundancy, high availability, and service resiliency.
• API-based: As microservices or containers are deployed in isolation, there needs to be a way for them to communicate so that the underlying service can be invoked. This is the job of an application programming interface (API). The purpose of an API is to enable individual services, microservices, or applications to communicate, as they act as secure connectors between loosely coupled services.
• Dynamically orchestrated: You might be thinking that microservices and containers are going to make life easy, but think again. As containerization becomes pervasive, managing containers becomes chaotic. As a result, there is a dire need for container orchestration tools. These tools are used to manage container lifecycles and version control, which can become challenging when there are hundreds or more containers to manage. Container orchestration tools provide the means for resource management, provisioning, and deployment using clusters of server nodes.
• Use declarative communication patterns: Cloud-native apps (CNAs) follow declarative communication patterns that have trust in the network to fulfill the developer’s intent of the desired state. Declarative patterns standardize a communication model, which shifts the functional tasks away from the application to a remote API or service endpoint.
• Designed for automation in CI/CD pipelines: Continuous integration and deployment are fundamental to cloud-native applications. This means that there must be extra logic in place to deal with the complexity of the pipelines.
• Expose health checks: Understanding the status of the application is critical in automation, such as in automatic scaling, recovery, and optimization. The application needs to instruct the platform it is running on about the state it is in, and exposing health checks allow the platform to track and monitor the application state in real-time.
• Collects telemetry data: CNAs often have service-level objectives (SLO). Therefore, a CNA must be able to collect telemetry data to be considered a cloud-native.
• Cloud Native vs Cloud-based apps: The problem with defining a technology is that very rarely is something new; more often than not, it will be an evolution rather than an invention. This is clear with cloud-native apps when we consider the differentiators between the terms cloud-native application, cloud-based applications, and even service-orientated architecture, as they are often confused. While they are all service orientated and superficially similar in purpose, they differ in design:
• Service-orientated architecture (SOA): This architecture is the grand daddy of them all as it was the first architecture to be designed as a service-orientated platform. However, SOA was popular long before the cloud emerged, so services communicated across a bus connecting on-premise servers rather than across a distributed network. Hence, although the principles are similar, the technologies, protocols, and constraints are very different.
• Cloud-based applications: These are applications that are designed to run on cloud platforms. As such, cloud-based applications have been redesigned to run on dynamic cloud infrastructure, but they are not typically designed to take advantage of the inherent characteristics of the cloud, such as dynamic pods, automatic scaling to infinity or zero, and zero downtime migration across nodes.
• Cloud-native applications: These applications are designed specifically for the cloud. Cloud-native application development is optimized for the inherent characteristics of the cloud and is adaptable to the cloud’s dynamic environment.

In short, the common cloud native features should provide scale, elasticity, and resilience, and serverless and microservices architecture are key technologies that help achieve those goals. The latter is where applications are broken down into functions or microservices and then packaged in lightweight containers to be deployed and orchestrated across a variety of virtual servers.

Hope this was helpful.