Why Is REST API Architecture Gaining Popularity in the Digital Industry?

DZone 's Guide to

Why Is REST API Architecture Gaining Popularity in the Digital Industry?

REST API Architecture is easier to use for the major important part, is more adaptable and has the following edge when compared to SOAP.

· Integration Zone ·
Free Resource

Connectivity is an amazing thing, by now we are all used to the instant connectivity that puts the world at our finger tips. From desktops or devices, we can purchase, post, pin, and pick anything anywhere. We are connected to the world and each other like never before, but how does it happen? How does data get from “here” to “there”?

How do different devices and applications connect to each other to allow us to place an order, make a reservation or book a flight with just a few touches or clicks? The unsung hero of this connected world is the application programming interface or API.

It’s the engine under the hood and is so behind the scenes that we have a habit of taking it for granted but it’s what makes possible all the interactivity we have come to expect and rely upon.

But Exactly What Is an API?

To speak plainly API is the messenger that takes requests, tells a system what you want to do and then returns the response back to you. To give you a familiar example think of an API as a waiter in a restaurant, imagine you are sitting at the table with a menu of choices to order from and the kitchen is the part of the system which will prepare your order.

What’s missing is the critical link to communicate your order to the kitchen and deliver your food back to your table; this is where the waiter or the API comes in.

Let’s Take a Real Example:

We are all familiar with the process of searching for airline flights online and in order to book your flight you interact with the airline’s website. You access their database to see if there are any seats available at a certain date and what the costs might be based on certain variables.

But what if you are not using the airline’s website which has direct access to the information? What if you are using an online travel service that aggregates information from many different airlines?

The travel service interacts with the airline’s API, the API is an interface that like our helpful waiter can be asked by the online travel service to get information from the airline system over the internet to book seats, choose meal preferences or baggage options.

It also then takes the airline’s response to your request and delivers it right back to the online travel service which then displays the information to you. The same process goes for all interactions between applications, data and devices. They all have APIs that allow computers to operate them and that is what ultimately creates connectivity.

What Are the Different Types of APIs That Exist?

API architecture can be implemented in two major ways, one the ways in implementing transfer of information between different APIs is SOAP and the other major way is REST. We have already established that APIs allow communication between two applications. Furthermore, we will see how exactly SOAP and REST APIs fit into the communication architecture.


SOAP APS or Simple Object Access Protocol is a web service that complies with the SOAP Web service specifications. These specifications are certain communication guidelines which are established by a central body called W3C and the basic set of specifications include:

  • SOAP
  • WSDL
  • UDDI

SOAP is a protocol that defines how two applications will communicate with each other. Two applications when talking to each other have to follow a common format and that common format has to be based using the XML language.

The XML in SOAP APIs have to follow a SOAP Message standard that consists of an Envelop, Header, and Body.


This is a very important but often misunderstood concept when it comes to web services so let’s decode what REST or RESTful APIs mean. REST stands for representational state transfer and is a web service that initiates communication between two applications using the principles of REST architecture.

REST architecture is an architectural style, this architecture does not follow any protocol, there are no strict specifications and there is no central body present that controls the specifications. This makes REST a design principle and one can use this principle to create any kind of service.

When these principles are applied when creating any web service we get RESTful Web service. Now let’s go a little more deep and ascertain the principles the REST architecture is based on.

Uniform Interface:

When we think about RESTful architectures, everything can be considered a resource. For example, if you are trying to create an application for employee management system. This application can be created using any language, on any platform, and for any platform. Similarly, any database can be used to handle backend services.

The concept of resources in a REST API defines that the user can define any information or any module as a resource. Considering the employee management system the creator can define a resource for employees, departments and any other module used in the application can be defined as a resource.


In a RESTful architecture all the responses and requests, all the communication between servers is stateless. This means that the server does not maintain any state of the system so the client has to send a request which is complete in itself. The request is not dependent on any of the previous requests made.

For example, if you are shopping online and adding items to your cart the server will not maintain the state of your cart so every time the user sends a request to the server it will include the current state fo your shopping cart.

In statelessness, as the server does not have the overhead of storing or maintaining the session therefore it improves the web service’s performance.


In the last protocol, we observed that the server does not maintain the state of any session in the case of RESTful architecture all the caching takes place at the client’s side. Whenever a client sends a request to the server, the server gives back the response which contains the actual data and along with other metadata that tells the client whether it has to store the response locally or not.

Layered System:

The REST principle states that whenever there is communication between the client and the server there can be multiple layers in between and these layers can be sued for a number of purposes like message translation to improve performance, caching, and a lot of other stuff.

Every layer in the communication has a certain task; the purpose of having multiple layers in the communication makes the system perform effectively improving speeds and longevity.

Code on Demand:

This is an optional constraint of RESTful Web Services it works when the user sends a request to get a response back. The response has the ability to run some code on the client’s side; this principle extends the functionality of the communication that is taking place.

Why Is REST Being Employed More?

REST is easier to use for the most part, is more flexible and has the following advantages when compared to SOAP.

There are no expensive tools required to interact with any web service. REST architecture has a smaller learning curve as it can be setup easily and requires no expert hands while making the communication model. It is efficient in use as it can also use the client’s server side to store information which is relevant for the client. REST uses smaller messaging formats and is fast as there are no extensive processing required. REST is also closer to other web technologies when it comes to design philosophy.

Opinions expressed by DZone contributors are their own.


{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}