Although there are several design models for web services, the two that dominate are SOAP (Simple Object Access Protocol) and REST (Representational State Transfer). Deciding which one will be best suited to your needs can be a difficult task. In a nutshell, SOAP is a web services access protocol that is standards-based and is older than REST. REST was actually made as a response to fill the gaps that SOAP lacks, and it also provides a simpler way to access web services.
SOAP, developed by Microsoft, was meant to take the place of binary technologies in the past that were not able to work with the internet the way we know it today. It is an XML-based protocol that allows multiple computers to communicate with each other. It works in many programming languages with varying degrees of difficulty. It also comes with error reporting that can be automated, which is important to your security, especially when using another company’s web service.
SOAP and REST have some unique differences that lend each its own set of strengths and weaknesses. Although they both share some similarities as far as the HTTP protocol is concerned, SOAP has a more defined set of patterns. The rules that exist within SOAP are key to understanding their main differences. The standardized rigidity of SOAP makes it more consistent. REST doesn’t have the same processing requirements and has mostly taken its place as the preferred API, however, they both rely on rules that have become established and agreed upon over time.
Since few web services support both SOAP and REST, it’s important that you know which protocol is best for your needs; that way, you can choose the appropriate web service to use. REST is easy to understand, even for beginners, but SOAP is an industry-standard due to its rigid and defined protocol. Here are more of the advantages of each:
SOAP is a great solution if your application requires a level of guaranteed security since it offers additional security standards. It also provides rigid specifications for a formal interaction between the provider and the consumer. This standardized structure provides built-in error handling along with pre-build extensibility.
REST is a much more flexible and simple web service to use than SOAP and works really well for those with limited bandwidth and resources and can be used with any browser. It uses the XMLHttpRequest object that almost all browsers support and also works well with AJAX. REST is also good for stateless operations as well as operations that need to be cached.
There are no expensive tools required to interact with REST, so it's much more accessible to the general public. In addition, it’s easy to use because it shares the same design philosophy as other web technologies, so there is a minimal learning curve compared to SOAP.
Both SOAP and REST have their advantages and disadvantages, but both can usually get the job done depending on the needs of your business. It’s tough for developers to draw a line in the sand when choosing one over the other. Their uniqueness makes them applicable over an array of requirements and uses, so it might be best to consider which web service works best for your company right now.