Architecture Layered, heavyweight Stateless, resource-based Client-driven, query language Remote procedure call
Data format XML JSON, other human-readable formats JSON Proprietary, often binary
Communication style Request-response Request-response Single request, multiple responses Request-response
Flexibility Less flexible, more structured Highly flexible, adaptable Very flexible, specifies only desired data Limited flexibility, specific function calls
Performance Generally slower due to heavier data format Can be faster due to lightweight format Efficient if querying specific data Highly efficient for internal microservices
Complexity More complex to develop and maintain Easier to develop and maintain Moderate complexity, requires schema learning Moderate complexity, depends on chosen RPC framework
Security Built-in security features like WS-Security Requires additional security layers Can be secure with JWT and other mechanisms Varies depending on framework and implementation
Typical use cases Enterprise integrations, secure transactions Public APIs, web applications, mobile apps Single data fetching requests, personalized APIs Internal microservices communication, high-speed data transfer
Popularity Declining, but still used in legacy systems Widely used, dominant API style Increasing popularity, particularly for complex data needs Primarily internal usage, growing adoption for public APIs