Why serverless? Advantages and disadvantages of serverless computing explained
Tags: serverless, azure, softwaredevelopment, cloud
Published: 2024-07-03 16:02:40

Nowadays, companies want to improve their IT infrastructure. One option is serverless. This allows developers to create and operate applications without having to worry about the server infrastructure.

Well-known services such as Azure Functions from Microsoft Azure and AWS Lambda from Amazon Web Services (AWS) are examples of how developers can run their application code serverless. However, these services are only part of what serverless offers. In addition to the ability to run code, databases, message brokers and API gateways can also be run serverless.

Serverless is an umbrella term for services that do not require their own server administration, scale automatically and are billed on a usage basis. These features make serverless an attractive option for companies that want to optimize costs, increase scalability and shorten time-to-market.

## What is serverless?
Serverless is a term that can be misunderstood. Serverless does not mean that there are no more servers. There are still servers on which your applications run. The difference is that you no longer have to take care of the servers. As a developer, you don't have to buy, deploy or maintain a physical server. You write your code, deploy it and the cloud provider takes care of the rest.

And that rest can be a lot. If you currently run your applications on-premise, you may be familiar with the following situations:

- You need new hardware and have to order it.
- The hardware needs to be installed.
- You have to make updates and keep the servers secure.
- If a server goes down, you need to know what to do.
This list can go on and on. With serverless, you don't have to worry about anything.

Serverless means:
- No server management: you no longer have to worry about the servers.
- The resources are automatically adjusted so that there is always enough capacity available.
- You only pay for the resources you use.

These features have advantages and disadvantages. Let's assume an HTTP endpoint is only called ten times a month. In this case, it is better to run serverless. You only pay for the ten calls. This is cheaper than running a server all year round.

The pay-as-you-go cost model is not always the best solution. If your requests are constant and highly predictable, it may be cheaper to run a fixed number of servers.

Whether serverless makes sense for your application depends on your specific needs and usage patterns. In later sections, I will explain how to do the evaluation.

## Comparison of on-premise vs. IaaS vs. CaaS vs. PaaS vs. FaaS
Switching from traditional on-premise models to modern cloud solutions can be a big improvement for many companies. To better understand the different models, here is a comparison:

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/gcu8ztkysd9ois82ztjm.png)

## On-Premise
With this model, the server is located in the company's own data center. All tasks, from hardware procurement, installation and maintenance to scaling and security updates, are the responsibility of the company. This costs a lot of money and requires many employees.

## Infrastructure as a Service (IaaS)
The first step into the cloud. Here, the cloud provider takes care of the hardware and virtualization. You no longer have to order or install physical hardware. Instead, you can set up virtual machines with just a few clicks. However, you still have to manage the operating system, scaling and application.

## Container as a Service (CaaS)
Container as a Service is a further development of IaaS. The cloud provider takes over the management of the container orchestration system, such as Docker or Kubernetes. This makes it easier to manage and scale containerized applications, but the company still has to maintain the container infrastructure and applications.

## Platform as a Service (PaaS)
The cloud provider also takes care of the operating system and the runtime environment. Developers only have to take care of the application, its scaling and configuration. PaaS does a lot automatically and relieves the IT department. Nevertheless, you can still do a lot yourself.

## Functions as a Service (FaaS)
FaaS stands for "Functions as a Service". The cloud provider takes over the management of the entire infrastructure. You only take care of the application code and functions. Scaling takes place automatically and is scaled up or down as required. Billing is based on actual usage (pay as you go). This is particularly good for applications with irregular or unpredictable loads.


Each model has its advantages and is suitable for different requirements and usage patterns. Serverless or FaaS is good if you are looking for a flexible, affordable and fast solution. Then you can focus on development and business value instead of worrying about infrastructure.

## Load distribution: a decisive factor for the choice of serverless
Serverless is a sensible architecture if the load distribution is right.

Let's imagine an application that has an even load from 7 am to 7 pm. In this case, serverless does not make sense. The load is even and predictable. It is not necessary to adjust the performance automatically. If each execution is billed individually, it does not make sense in terms of costs.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/sjaywzughg400bdsqpjw.png)

The situation is different for applications with unpredictable loads. Let's take an application that receives many requests at different times. Sometimes there are few requests, sometimes many. This pattern shows that serverless could be a good solution. Serverless automatically adapts to the current demand. You only pay for the resources you use.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/ilxywkobfeq9wc79nihg.png)

You need to know what your application needs and how it is used. A precise analysis shows whether serverless is the right choice. Serverless is good for applications with fluctuating loads. It scales automatically and is billed according to consumption.

If your application has a stable and predictable load, a traditional cloud solution might be better. For irregular and unpredictable loads, serverless is better because it adjusts automatically and is cheaper.

## Conclusion: Serverless - an innovative solution with clear advantages and some challenges
Serverless is a technology that makes the management of servers superfluous. It ensures that applications can be developed and provided faster and more cost-effectively.

Serverless has the following advantages:
- No server management: developers can concentrate on the code without having to worry about the infrastructure.
- Serverless applications scale automatically as more or fewer users access them. This is particularly practical when user numbers fluctuate greatly.
- Cost optimization: You only pay for the resources you use. This is particularly cost-efficient when the number of users is low.
- The time-to-market is shorter because developers can concentrate on developing new functions.

Serverless also has disadvantages:
- You are dependent on one provider. If you want to switch, it can be difficult.
- Companies have less control over the hardware and operating system.
- If there is little use, it takes longer for functions to start. The instances are then scaled down to zero. However, some providers have already developed solutions for this.

Serverless is particularly suitable for applications that are used a lot or a little. The automatic scaling and usage-based billing are very advantageous in such scenarios. For applications with a stable and predictable load, traditional cloud models such as IaaS or PaaS are often more favorable.

## Get the Serverless Cheatsheet now!
Are you ready to utilize the full potential of your software? Our cheatsheet gives you an overview of the differences between IaaS, PaaS and FaaS and helps you find the best solution for your next application. Don't miss out on this valuable resource to help you make informed decisions and optimize your IT infrastructure.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/npalv9n9r11wtarlg7mc.png)

## References

- [Was ist Serverless](https://www.florian-lenz.io/blog/was-ist-serverless)
- [Was ist Serverless? | Azure Serverless Computing einfach erklärt](https://youtu.be/OhK5FX5PJyc)