How to Choose between SOAP and REST?

Table of Contents

What is SOAP?

SOAP(Simple Object Access Protocol)is a network communication protocol based on XML for distributed computing on the Internet. SOAP messages can be transmitted using different protocols, such as HTTP, SMTP, MIME, RPC, etc. SOAP provides the message protocol layer of the Web Services Protocol Stack for Web Services. It is a protocol based on XML, consisting of three parts:

  • Envelope:A wrapper that identifies the message as a SOAP message and provides namespace declarations. Namespaces provide the semantic context for the elements in the SOAP message body.
  • Header:An optional element that can contain meta data, such as authentication information, localization support, and delivery paths.
  • Body:Contains the payload of the message. It is either a request to a Web service or a response to a Web service request. The response may be an error message, called a SOAP fault.
SOAP Message Building Blocks
SOAP Message Building Blocks
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The Difference Between SOAP and REST

Both are HTTP protocols, but the difference is that:

  1. Transmission protocol: SOAP uses HTTP, SMTP, TCP or UDP, etc. as the transmission protocol, while REST usually uses HTTP protocol.
  2. Data format: SOAP uses XML format to transmit data, while REST uses a relatively lightweight format, such as JSON or XML, etc.
  3. Operation style: SOAP uses the Remote Procedure Call (RPC) operation style, while REST uses the resource-based operation style.
  4. Design principles: SOAP follows relatively strict standards and specifications, while REST emphasizes simplicity, high degree of freedom, and easy expansion.
  5. Transmission efficiency: SOAP uses a relatively complex XML format and RPC operation style, resulting in low transmission efficiency; while REST uses a relatively lightweight data format and resource operation style, resulting in high transmission efficiency.

SOAP vs REST Use Cases


  • Scalable and scalable solutions, especially in Web applications.
  • Simple data transfer between client and server, and support for multiple formats, such as JSON, XML, etc.
  • Support cross-language communication, because REST is based on HTTP and URL, which makes it easier to cross platforms.


  • A relatively strict protocol that can provide high security and transaction support.
  • Transmit complex, highly structured data in large enterprise systems.
  • Ensure the integrity of messages to ensure that data is not lost or damaged during transmission.