What is FaaS? Function-as-a-service explained
FaaS, IaaS, PaaS… There are lots of terms in cloud computing and naturally – lots of confusion! FaaS is yet another cloud server deployment that is mostly used by developers to develop, troubleshoot and run code in microcosm. In fact, FaaS is a type of serverless computing that is favoured by many developers due to its ease of use, without them having to configure their own cloud infrastructure.
Here we’ll explore what FaaS is, how FaaS works, the FaaS cloud deployment in relation to others, plus use cases for FaaS and their many advantages.
What is FaaS in cloud computing?
Function as a Service (FaaS) is a type of cloud computing that provides a platform for users to develop, run and manage their applications, without having to build the infrastructure that hosts the environment. If you wanted to build the infrastructure, you could use an IaaS to facilitate FaaS use.
Developers can use FaaS to create small, self-contained code functions. These functions can be triggered by specific events, such as user actions or data changes, and executed on-demand without the need to manage the servers themselves – instead, this sits with the hosting provider. With FaaS, developers focus solely on writing the code for their functions, and the cloud provider handles everything else, including scaling and resource allocation, which can be scaled up or down upon request. Plus, this convenience is possible due to the automatic scalability of FaaS.
How does FaaS work?
A FaaS works by having its physical hardware, virtual machines (VM) and web servers handled by a cloud service provider. When looking into FaaS, you may come across the term microservices – but what are these in relation to FaaS and how does it work?
Imagine you have a box of jigsaw pieces, they’re exactly that – pieces! Not one whole picture. You could think of these jigsaw pieces as microservices that work together to make an entire application, of which devs can access to tweak, fix or upgrade, as opposed to accessing the entirety of the app or software’s code. In an actual application, a microservice could be part of a program that processes payments or manages a database.
With this in mind, Microservices can be seen as building blocks that create manageable parts of an application, which can be broken down into even smaller functions and handled by a FaaS cloud provider.
How do microservices and FaaS work together?
FaaS, as previously established, lets developers create small, self-contained functions designed for specific tasks.
Microservices with FaaS work in harmony, with the possibility of each microservice being further broken down into smaller functions and implemented within a FaaS environment. When an event activates one of these functions by a user, it operates in a secure and isolated environment. This brings a whole host of advantages to a developer, including improved modularity, flexibility, and optimal resource management.
How does FaaS impact scalability?
FaaS allows developers to execute small amounts of code without managing underlying cloud infrastructure – so how does this impact the scalability of software, and then a business or project?
1. Auto-scaling potential
As workload and demand increase, a FaaS provider can be allocated additional resources on an automatic basis, which reduces (and in some cases, eliminates) downtime, by allowing the FaaS cloud server to handle sudden spikes in traffic.
2. Scale on a granular level
If there’s a small component of your application that requires more resources, then it’s possible for your FaaS provider to scale these sections on demand. This is beneficial for resource and cost management, as it can prevent overprovisioning an entire cloud server.
3. FaaS when required
Another advantage of FaaS’s scalability potential is the elimination of idle time. Unlike traditional server-based applications, where resources may remain idle during low-demand periods, FaaS instances only exist while actively processing requests. This dynamic resource allocation ensures optimal resource usage and reduces operational costs.
4. Workload distribution
The decoupled architecture promoted by FaaS ensures stateless, event-triggered communication among functions. This decoupling facilitates parallel processing, allowing workloads to be distributed across multiple function instances, further enhancing scalability.
5. Integrate third-party resources seamlessly
FaaS platforms often offer seamless integration with external services and event sources, allowing developers to leverage third-party resources effortlessly - which is great if you have preferred resources and want to adopt a multi-cloud or hybrid cloud approach to your business. These integrations help distribute tasks and enable efficient scaling of applications to meet growing demands.
What is the relationship between IaaS, PaaS and FaaS?
We cover IaaS, Platform as a Service (PaaS) and even Software as a Service (SaaS) in our respective cloud computing guides, but what are the differences and key relationships between IaaS, PaaS and FaaS?
IaaS, PaaS and FaaS are all types of cloud computing with varying levels of dev capabilities and infrastructure – with IaaS being the cloud computing type that allows devs to build their own infrastructure.
PaaS, on the other hand, presents a comprehensive platform for application development, deployment, and management. It encompasses an integrated set of tools, services, and development frameworks, abstracting much of the underlying infrastructure complexity. This empowers developers to concentrate on coding and building applications efficiently.
Ultimately, IaaS forms the foundation for PaaS, as it provides the essential infrastructure required to run platform services. PaaS, in turn, builds on IaaS by abstracting the underlying infrastructure and offering higher-level services and tools for developers. Plus, PaaS can incorporate FaaS capabilities, allowing developers to deploy serverless functions as part of their applications, further simplifying the development process.
What are the use cases for FaaS?
Function as a Service (FaaS) offers a versatile and event-driven execution environment that makes it suitable for various use cases in modern application development and cloud computing. Let's explore some of the many use cases of FaaS in detail:
1. Web and mobile applications
FaaS can serve as the backend for web and mobile applications, handling specific tasks and functions. This includes:
- User authentication (such as two-factor authentication)
- User management
- File processing
- Database management
Plus, developers can build these individual functions, and the FaaS platform automatically manages the scaling and execution of these functions based on incoming events.
2. Chatbots and online virtual assistants
Ever spoken to a chatbot for a query you had? It was probably powered by FaaS! FaaS can power the backend logic for chatbots and virtual assistants. These conversational interfaces can utilise functions to process user queries, retrieve information from databases or external services, and provide real-time responses to users.
3. Real-time data processing
FaaS is excellent for real-time data processing and analytics. It can be triggered by various events, such as messages from a message queue, updates from IoT devices, or data streams from log files. This event-driven approach allows for responsive and scalable data processing, enabling applications to react in real time to changing conditions.
4. IoT applications
With its auto-scalability and event-driven nature, FaaS is well-suited for handling incoming data streams from IoT devices. Functions can process data from multiple devices in parallel, making it efficient for IoT data processing and analysis.
5. Event-driven automation
FaaS is ideal for automating repetitive tasks based on events. For instance, when an image is uploaded to a storage system, a function can be triggered automatically to resize, optimise, and store the processed image. This is an especially useful function if you host a site where users upload media but are likely to skip resizing their images. Similarly, FaaS can automate actions like sending notifications, processing orders, or updating databases based on specific events.
6. Dev testing
Of course, FaaS is valuable for quick prototyping and testing of specific coded functionalities. Developers can rapidly build and deploy functions to assess their viability and then integrate successful prototypes into larger applications.
7. Schedule backups
While FaaS is incapable of backing data up – developers can create a backup function to trigger it at designated intervals. The backup function can carry out the essential backup operations and save the data in a preferred cloud storage service.
The benefits of using FaaS
1. It’s cost-effective
Like most public clouds, FaaS uses a pay-as-you-go model. This means you’re only charged on your actual usage, i.e. execution time of functions. This makes FaaS a cost-effective solution, as you’re not billed for idle time.
2. FaaS is automatically scaled
Need more resources? FaaS platforms are typically run on an auto-scale basis during periods of high demand. This means you won’t have to request more resources manually, which can be time-consuming.
3. Enhances productivity
As developers only use FaaS to develop small snippets of codes for specific functions without needing to configure the cloud’s infrastructure (let alone manage it), it means developers can focus on getting to work on what they do best.
4. Reduce dev resources
As a FaaS and its infrastructure and management are handled by a cloud provider, this means businesses don’t need to hire additional devs, meaning overheads can be reduced in the long run.
5. Integrate third-party services with ease
FaaS can easily work with third-party services by connecting its small functions to external events. These events can come from various sources like HTTP requests, databases, or other cloud services. By configuring the functions to respond to these events, developers can integrate third-party services seamlessly.
For example, a FaaS function could receive data from an external API, process it, and send the results to another service. This flexible and scalable approach allows developers to build powerful serverless applications that leverage the capabilities of multiple external services.
The disadvantage of using FaaS
1. Vendor lock-in
While FaaS is quite different from other public clouds, it’s still ultimately managed by a cloud service provider. Said provider may only allow specific code for your functions, so if you wanted to migrate to a different provider, then devs may need to account for the time it may take to adapt code to suit the new provider, which may make businesses put off the switch altogether.
2. Auto-scaling may not be as reactive
FaaS providers are designed to scale as your business grows. However, some providers scale quicker than others. So depending on the FaaS provider you’re with, there’s still a small risk of downtime, which could lead to a loss in customers.
3. Could become less cost-effective
FaaS is a cost-effective solution in a general sense. However, if your business is receiving a constant stream of high traffic, then granular billing may not be as cost-effective in the long run, and it could make more sense to switch to a different public cloud provision that allows you to accommodate this.
4. Testing can get complex
It’s all good and well testing your self-contained code, but if you run the full program or user journey and there are still issues (or another arises as a result of your code), then further investigation and resources may be needed – which can get complicated and time-consuming.
How can I get started with FaaS?
Kubernetes and Knative for FaaS implementations is a preferred choice by many devs, as the former is an open-source container orchestration tool that allows you to manage and deploy containerised applications. This setup gives you the flexibility to choose your cloud provider or even run Kubernetes on-premises, offering a viable option for those seeking greater control over their serverless infrastructure and avoiding vendor lock-in. With Kubernetes, you can deploy your FaaS functions as containerised applications, providing a robust and scalable infrastructure.
When paired with Knative, it extends Kubernetes to provide a higher-level abstraction for serverless workloads. It offers two main components: Knative Serving and Knative Eventing. It’s what enables you to deploy and manage serverless applications on Kubernetes. It automates the scaling of your functions based on incoming traffic, ensuring efficient resource utilisation and cost savings. Knative Serving allows your functions to scale down to zero when there's no traffic too – reducing costs and maximising efficiency.
Frequently asked questions about FaaS
What is FaaS vs PaaS?
There’s often a bit of confusion between FaaS and PaaS – which we hope we can clear up.
FaaS represents a subset of serverless cloud computing where developers create and deploy individual functions that respond to specific events or triggers. Here, developers focus solely on building these functions, without the burden of managing servers or infrastructure. The cloud provider assumes responsibility for server provisioning, scaling, and maintenance, charging developers based on the actual execution time of their functions.
On the other hand, PaaS serves as a cloud computing model that lets developers build, deploy and manage entire applications – essentially a step-up of FaaS, if you will. PaaS platforms offer a complete development and runtime environment, replete with tools, libraries, databases, and middleware, streamlining the application development process. Unlike FaaS, which operates at the function level, PaaS enables the development of full applications with multiple components and services.
Are FaaS and serverless the same thing?
FaaS and serverless computing are related, but not exactly the same. FaaS is only one part of the serverless computing and cloud computing model where developers write small pieces of code called functions, and the cloud provider runs these functions automatically when needed. Developers don't have to worry about managing servers or infrastructure. FaaS is like a building block approach where you only pay for the time your functions run, making it cost-efficient and scalable.
Serverless computing, on the other hand, goes beyond just functions. It includes other various managed services offered by cloud providers, such as databases and storage, where the provider handles the underlying infrastructure. Serverless refers to a broader category where the server is completely hidden from the end-user, abstracting away all server management so devs can focus on what they do best – developing! The goal is to let developers focus on writing code and building applications without managing servers.
We hope this has provided all you need to know about the FaaS public cloud model, plus its relation to other cloud deployments. Interested in other types of servers? As well as being a Cloud Service provider, we also provide VPS, Dedicated Servers, Bare Metal and much more at great prices and 99.99% server uptime. Contact us to find out more about our servers and how to choose the best hosting solution for your needs.