Architecture Evolution

From infoq.com:

For the last 50 years or so, software architecture and application hosting models have experienced major transformation from mainframes to microservices and serverless.

Figure 1 shows this evolution of architecture models and the paradigms they promoted.

The article goes on to discuss serverless, as one of the current cloud architectures:

Another trend that has received a lot of attention in the last few years is serverless architecture, also known as serverless computing. Serverless goes a step further than the PaaS model in that it fully abstracts server infrastructure from the application developers.

In serverless, we write business services as functions and deploy those functions to the cloud infrastructure. Some examples of serverless technologies are Amazon Lambda, Spring Cloud Function, Google Cloud Functions, and Microsoft Azure Functions.

The serverless model sits in between PaaS and SaaS in the cloud-hosting spectrum, as shown in the diagram below.

Here’s a good breakdown of the suitability of each architecture for different purposes:

Finally, a summarised image: