Curl, what is it? Curl is a command line tool that allows you to transfer data from server to another device using a wide range of supported protocols (HTTP, FTP, TFTP, SMTP to name a few). The default protocol curl uses is HTTP. For us network folks, this makes life a little easier. The main reason I am writing about this is to explain some of the curl capabilities for us to consume network device/appliance application programming interfaces (APIs) in later posts.

Since we will be using curl in later posts to test/consume APIs it is important to understand HTTP methods that we can use. It is also important to understand what the CRUD model and RESTful applications are/mean.

So let's start with a brief overview of all 3. HTTP methods allow us to to send and/or retrieve information between applications. CRUD is a model that is followed by most APIs that are built that is an acronym for (Create, Read, Update, Delete), which allows us to manage resources via RESTful APIs. REST is an acronym for REpresentational State Transfer, which essentially means we we are transferring a representation of some resource between two devices. So in short, RESTful APIs are services that implements the REST standards that allow us to utilize the CRUD model.

So, here are how CRUD & HTTP methods relate to each other:

  • HTTP POST = Create

  • HTTP GET = Read

  • HTTP PUT = Update

  • HTTP DELETE = Delete

Note that there are other HTTP methods, but these are the most commonly used ones.

Ok so now that we have a better understanding of how the 3 correlate with each other, let's breakdown curl a bit more:

Curl is a great tool that quickly lets you test consuming an API. In some past experiences I have used curl to quickly grab (GET/Read) a unique identity string that I needed to place in a python automation script. Most network appliances have software development kits (SDKs) which provide a great way to understand the capabilities you have when consuming the respective APIs.

Stay tuned for further posts with curl demos & command breakdowns. Cheers!


Recent Posts

See All

HTTP Methods & Status Codes Tidbit

In this tidbit I want to touch on different types of HTTP Methods & the types of HTTP status codes you may encounter when consuming APIs in regard to automation. HTTP Methods: GET = get user info PATC

FMC & FTD Communication/Registration Tidbit

In this tidbit I want to cover the basics in regard to FTD & FMC registration. I also intend on covering how the two communicate with each other as this can be helpful when having registration issues

ASA MultiContext Mode Packet Classification Tidbit

In order to understand how traffic flows through the segregated contexts it is important to understand how the ASA determines the context in which it will send the packets. This process is known as c