Function as a service

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Function as a Service ( FaaS ) is a category of cloud computing and is to be classified between Backend as a Service (BaaS) and Software as a Service (SaaS) and in the context of “Serverless Computing”.

properties

With function as a service everything below the business logic is taken for granted. This includes server , network , storage, possibly virtualization levels, operating system , runtime environment , data and the application itself.

  • Only the business logic with the functions is implemented itself. Therefore, applications implemented with FaaS are stateless .
  • An external database server or network file system must therefore be connected to persist data .
  • FaaS enables particularly simple scalability, since the stateless functions can be horizontally scaled trivially .
  • By paying for each function call, large capacities can be kept available, especially with heavily fluctuating loads, which only have to be paid for when actually used. If no one is calling the function, there are no costs.
  • Self-contained functions are easy to maintain and update.
  • Event-driven and reactive: With FaaS there is no running server process. Instead, there is a function call as soon as a trigger event has been triggered, for example an HTTP call.

Demarcation

With Function as a Service, only the business logic itself is managed, while with Software as a Service this is managed by the SaaS provider. To distinguish it from Backend as a Service, FaaS only implements individual functions, not entire applications.

use cases

  • Alexa skills
  • Connection of several SaaS systems ( glue code )
  • Single-page applications
  • Compute-intensive components that are stateless
  • Timed tasks

FaaS provider

  • AWS Lambda ( Amazon )
  • Google Cloud Functions ( Google )
  • Azure Functions ( Microsoft )
  • IBM Cloud Functions ( IBM , OpenWhisk)
  • Oracle Cloud Fn ( Oracle )
  • Webtask.io
  • Hook.io

Open source solution

There is also a Function as a Service solution that is open source and can be hosted on premises . This is called Open Whisk and is a project of the Apache Software Foundation . IBM Cloud Functions uses OpenWhisk internally.

See also

credentials

  1. ↑ Serverless Architectures Martin Fowler, https://martinfowler.com/articles/serverless.html Accessed March 6, 2018
  2. ↑ Function as a Service , Steffen Jacobs, https://blog.oio.de/2018/02/14/function-as-a-service/ , access date: March 6, 2018
  3. ↑ Serverless Computing , Lars Röwekamp, https://www.heise.de/developer/artikel/Serverless-Computing-Teil-1-Theorie-und-Praxis-3756877.html , access date: March 6, 2018.
  4. ^ What Is Function-as-a-Service? Serverless Architectures Are Here! , Matt Watson, https://stackify.com/function-as-a-service-serverless-architecture/ , accessed March 6, 2018