New Training: Explain APIs in the SDN Architecture

In this 7-video skill, CBT Nuggets trainer Knox Hutchinson explores and breaks down the basics of an API and how it relates to the SDN world Watch this new Cisco training.

Watch the full course: Implementing and Operating Cisco Security Core Technologies

This training includes:

• 7 videos

• 27 minutes of training

You’ll learn these topics in this skill:

• Introducing APIs and SDN

• What is an API anyway?

• The Northbound API

• The Southbound API

• The Eastbound API

• The Westbound API

• Summarizing APIs and SDN

How APIs Fit in with Software-Defined Networks

In the programming world, an API is probably considered the most important application development concept. It's the most useful tool that programmers use to interface applications with.

API stands for an application programming interface. An API can come in many forms and sizes, but it's nothing more than an instruction set in the form of a black box that developers use to process data.

APIs can be something private. Many software development paradigms now encourage building APIs for an application to interact with. These APIs are typically for performing specific types of tasks like resetting an account password.

APIs can also be public. Azure and AWS provide APIs for their cloud products. For instance, a programmer can use the AWS API to push a file from their application to their S3 account for storage.

In both instances' APIs are used by developers to perform some kind of task. They are a recipe for doing that. The beautiful thing about most APIs is that they abstract away the complexities of the application and, even in many cases, the programming language used for that application so they can be used more generically. For instance, if one developer writes an API in PHP, another developer can use that API with their application written in JavaScript.

So, how does this all fit in with software-defined networks? APIs are the bridges that network administrators use to control the network. Typically, the SDN API sits between the SDN controller and the application itself. The application calls on these APIs which will then hand off instructions to the SDN controller to configure the network.

For instance, an application might call on an API to configure bandwidth limitations. The API provides a programmatic way for network engineers to 'speak' to the network through the SDN-controller without having to configure the network itself. Developers will use that API to control the network instead. This process enables things like automation.