What Are The Different Layers Which Define Cloud Architecture?

Hardware Layer: This bottom most layer of cloud architecture, the hardware layer, primarily deals with all the hardware powering clouds. The hardware includes but is not restricted to routers, servers, switches, power and cooling systems.

Infrastructure Layer: Also called the virtualization layer, the infrastructure layer is where all the servers are pooled together into one.

Platform Layer: The platform layer comprises the operating system and other requisition structures and is based over the infrastructure layer.

Application Layer: As the name suggests, the application layer - the topmost layer - contains applications that directly interact with the end-user.

Cloud computing architecture is organized into multiple layers to enhance operational efficiency. At the top is the Cloud Controller (CLC), which oversees the management of virtualized resources such as servers, networks, and storage. Below this is the Walrus layer, functioning as a storage controller to handle user data demands.

The Cluster Controller (CC) facilitates virtual networking between Virtual Machines (VMs) and external users. The Storage Controller (SC) serves as a block-form storage device that Virtual Machines can dynamically attach to as needed.

Finally, the Node Controller (NC) operates as a hypervisor, managing Virtual Machine activities. This includes tasks like execution, monitoring, and the termination of multiple instances. These layers work together seamlessly to ensure an efficient and scalable cloud infrastructure.

IaaS - Infrastructure as a service. A cloud service is said to be IaaS when the provider is responsible for creating the entire virtualization environment for the client. The provider will setup the cloud, pool resource of the server together, turn on the lights and hand the keys of the cloud to the client. It is the bottom most service that can be sold to the client.

PaaS - Platform as a Service. When the provider itself configures an operating system on the infra, creating a ready platform to be used for various needs, it is called the PaaS or Platform as a Service. PaaS is mostly used by web developers for launching VMs as it gives them a ready made platform to start developing applications as per their needs.

SaaS - Software as a service is the topmost service layer that can be sold among various layers of cloud architecture. Of all types of cloud computing, this one involves the end-user and the underlying hardware the least. In SaaS, the client is not at all concerned with the layers underpinning the cloud and only works at the topmost layer.

Which type of Cloud Computing is the Best?

It is difficult to weigh the various types of cloud computing on the same scale. Each service or the layer has its own characteristic advantage. Say, the IaaS is the most suitable for organizations who covet the ultimate control of their cloud platform. PaaS is more apt for users who want an Operating System or any other software pre-installed in the cloud. Even if these users were to opt for IaaS, they would reap no added benefits because their requirements are different altogether. Similarly, software as a service is meant for less proficient users, who only need an application to perform specific functions. SaaS clients only concern themselves with the applications and not the cloud architecture. Some users might not even have an idea that their service is running with cloud computing underlying it.

Layers of Cloud Computing

Cloud computing consists of 3 different layers:

1) Infrastructure as a Service (IaaS): IaaS is the basic layer of the cloud that comprises hardware and network. That said, IaaS is different from a regular server as it comes with two key features of cloud technology-virtualisation and scalability. IaaS service providers scale this layer in such a manner that the additional cost of adding more storage or bandwidth is minimal. Owing to virtualisation, these providers are able to use up to 90% of their computing resources in contrast to traditional hosting services where servers may lay idle at times.

2) Platform as a Service (PaaS): This layer of the cloud caters to the requirements of software developers as it is the place where new applications are developed. You can use PaaS services to build and test your applications on the cloud before deploying them. In fact, it is designed in such a manner that it supports the entire lifecycle of an application, right from building, testing and deployment to maintenance and updating. Like IaaS, PaaS includes infrastructure, but also includes development tools, database management systems and much more.

3) Software as a Service (SaaS): The third and final layer of the cloud comes with a complete software solution. Here, organizations rent the usage of a SaaS application, and users connect to it by means of the internet. The application, therefore, needs to be web-based server so that it can be accessed from anywhere. In this case, the service provider offers both the software and the hardware.