SOAP, or Simple Object Access Protocol, is a protocol used for exchanging structured information in the implementation of web services in computer networks. It relies on XML (Extensible Markup Language) for its message format and typically uses application layer protocols such as HTTP, SMTP, TCP, and others for message negotiation and transmission[10][12].
Key Characteristics of SOAP
Protocol-Based: Unlike REST, which is an architectural style, SOAP is a protocol with strict standards and rules for communication between client and server[4][15].
XML Messaging: SOAP exclusively uses XML to format its messages, which ensures that the data is both human-readable and machine-readable[1][2][5].
Transport Independence: SOAP can operate over various protocols, including HTTP, SMTP, and more specialized protocols like Microsoft Message Queuing (MSMQ)[1][3][10].
Extensibility: SOAP supports extensibility through XML namespaces and custom header elements, allowing developers to add functionality as needed[1][12].
Security: SOAP has built-in security standards such as WS-Security, which supports digital signatures, tokens, and encryption to ensure message integrity and confidentiality[1][3][4].
Standardized Error Handling: SOAP uses a fault element to communicate errors that occur during message processing, allowing for consistent error handling across different systems[1][12].
Advantages of SOAP
Platform and Language Independence: SOAP allows applications built on different platforms and written in different programming languages to communicate with each other[10][12].
Built-In Error Handling: The standardized error handling mechanism in SOAP helps in consistent error reporting and handling[1][12].
Security: SOAP's support for WS-Security and other security standards makes it suitable for applications that require high security, such as financial and healthcare systems[1][3][4].
Extensibility: The protocol's extensibility allows for the addition of new features without affecting existing functionalities[1][12].
Disadvantages of SOAP
Complexity: SOAP can introduce complexity into a system due to its strict standards and extensive use of XML, which can be verbose and lead to larger message sizes[1][2][5].
Performance: The XML-based messaging can result in greater bandwid...
