Software Defined Networking

NETCONF as defined in RFC 4741 and RFC 6241 is an IETF standard that uses the YANG data models to communicate with various devices on the network. NETCONF can run over SSH, TLS and Simple Object Access Protocol (SOAP). Some common use cases for NETCONF: Collecting status of specific fields Changing the configuration of specific…

Yet Another Generation (YANG) modelling language, defined in RFC 6020 uses data models. Data models are used to describe whatever can be configured on a device, whatever can be monitored device, and all the administrative actions that can be executed on a device, including all the notifications that a device can generate. All of these…

Cisco DNA Centre expects all incoming data from the REST API to be in JSON format. HTTP POST function is used to send the credentials to the DNA Centre Controller. Cisco DNA Centre uses basic authentication to pass a username and password to the Cisco DNA Centre Token API to authenticate users. The API is…

Code Result Reason 200 OK Using GET or POST to exchange data with an API 201 Created Creating resources using a REST API call 400 Bad Request Request failed due to client side issue 401 Unauthorised Client not authenticated to access site or API 403 Forbidden Access not granted based on credentials that were supplied…

Extensible Markup Langauge Extensible Markup Language (XML) is a tag based language. The tag must begin with a ‘<‘ symbol and end with a ‘>’ symbol. A start tag named named interface would be represented as <interface> The tag must also be closed with an end tag, known as </interface> One key feature of XML…

Postman is an application that makes it possible to interact wiht APIs using a console-based approach. Postman allows for the use of various data types and formats to interact with REST-based APIs The Postman application has sections that can be interacted with: History History shows a list of all recent API calls using Postman Collections…

An API that uses REST is often referred as a RESTful API. RESTful APIs use HTTP methods to gather and manipulate data. As there is a defined structure on how HTTP works, HTTP offers a consistent way to interact with APIs from multiple vendors. REST uses different functions to interact with data: HTTP Functions HTTP…

An example of southbound API is if a network operator makes a change to a switches configuration in the management software of the controller. Changes are pushed down from the management software to the network switch using a Southbound API.

Northbound APIs are used to communicate from a network controller to its management software. Cisco DNA Centre has a software graphical user interface that is used to manage the network controller. When a network operator logs into that controller to manage its network, the information is passed from the management software is utilising a Northbound…

Another popular method of communicating with network devices along with the command line interface is the application programming interface, or API. APIs are mechanisms to communicate with application or other software. They can be used to communicate with various components of a network device through software. It is possible to use APIs to configure or…