Service-Oriented Architecture (SOA) Questions and Answers for Viva

Answer-1: SOA is an architectural pattern that allows services to communicate over a network. These services are loosely coupled, enabling flexibility and scalability.

Answer-2: SOA allows for reusability, interoperability, flexibility, and scalability. It also makes the system easier to maintain and integrates easily with other systems.

Answer-3: Some key principles are loose coupling, reusability, discoverability, composability, and autonomy.

Answer-4: Microservices are smaller, independently deployable components whereas SOA is more general and can encompass larger service components. Microservices focus on specific business capabilities.

Answer-5: Web services are a way of enabling communication between applications over the internet using standard protocols like SOAP or REST.

Answer-6: Loose coupling means that services in SOA can interact without being dependent on each other?s internal workings. Changes in one service should not affect others.

Answer-7: A service registry is a directory where services in SOA are registered and can be discovered by other services.

Answer-8: SOA promotes reusability by ensuring that services are designed to be modular, reusable, and discoverable across multiple applications.

Answer-9: The ESB acts as a middleware that facilitates communication and integration between different services in SOA. It ensures service interaction and routing.

Answer-10: SOAP, REST, JMS, and HTTP are commonly used protocols for communication between services in SOA.

Answer-11: SOAP (Simple Object Access Protocol) is a protocol for exchanging structured information in the implementation of web services.

Answer-12: REST (Representational State Transfer) is an architectural style that uses stateless communication and HTTP for web services.

Answer-13: SOAP is a protocol with a strict set of rules, while REST is an architectural style. REST is lightweight and uses HTTP, whereas SOAP can work with other protocols.

Answer-14: WSDL (Web Services Description Language) is an XML-based language used to describe the functionality offered by a web service.

Answer-15: UDDI (Universal Description, Discovery, and Integration) is a specification for a directory service to publish and discover web services.

Answer-16: Service Orchestration is the process of coordinating multiple services to achieve a specific business process or workflow.

Answer-17: Service composition is the process of combining multiple independent services to create a new service.

Answer-18: SOA ensures scalability by allowing services to be distributed across multiple servers and by enabling easy addition of new services as the business grows.

Answer-19: A service consumer is a client or application that invokes a service in SOA. Examples include a mobile app calling a payment service.

Answer-20: Challenges include complex governance, high initial cost, integration with legacy systems, and ensuring security and performance.

Answer-21: SOA handles security through methods like WS-Security, which ensures secure communication, authentication, and authorization of services.

Answer-22: A service contract defines the interface, operations, and data formats that services in SOA adhere to.

Answer-23: Service abstraction means that consumers interact with services through defined interfaces without knowing the internal workings of the service.

Answer-24: A message broker is a middleware component that routes messages between different services, ensuring communication within the SOA framework.

Answer-25: Service discovery allows clients and other services to locate and invoke services dynamically within the SOA environment.

Answer-26: A service provider is a component or system that provides a service that can be consumed by other services or clients.

Answer-27: SOA allows legacy systems to be integrated with modern services through the use of service wrappers, making them compatible with newer technologies.

Answer-28: A SOAP header is used to provide additional information for the SOAP message, such as security, transaction management, or routing details.

Answer-29: XML is used to structure data in a way that is platform-independent, making it ideal for service communication in SOA.

Answer-30: An ESB is a more advanced form of message broker that provides additional capabilities like routing, transformation, and protocol mediation in a service-oriented environment.

Answer-31: Services in SOA interact via standardized messaging protocols, usually through a service bus or direct communication over HTTP/SOAP.

Answer-32: Interoperability in SOA means that services can communicate and work together across different platforms and technologies.

Answer-33: Common tools include Apache CXF, JAX-WS, Mule ESB, and Oracle SOA Suite for building and managing services.

Answer-34: SOA and cloud computing both emphasize service-based architectures. SOA enables the creation of reusable and modular services that can be consumed in the cloud.

Answer-35: Service versioning allows different versions of a service to exist simultaneously, ensuring backward compatibility with existing consumers.

Answer-36: An API Gateway serves as an entry point for API calls, providing routing, security, rate limiting, and monitoring for services.

Answer-37: BPEL is a standard for defining business processes within SOA, enabling automation and coordination of service interactions.

Answer-38: SOA can be complex to implement, costly, and may lead to performance issues if not properly managed, especially with high-volume services.

Answer-39: SOA improves flexibility by allowing the addition, removal, and modification of services without disrupting the entire system.

Answer-40: A synchronous message requires an immediate response, while an asynchronous message is processed without waiting for an immediate reply.

Answer-41: Data transformation is crucial for converting data formats between different services, ensuring compatibility and proper data exchange.

Answer-42: An SLA defines the expected performance, reliability, and availability requirements for a service, ensuring that service consumers have clear expectations.

Answer-43: Orchestration involves a central controller to manage service execution, while choreography allows services to interact autonomously.

Answer-44: SOA incorporates fault tolerance by using techniques like retries, compensation transactions, and failover strategies to ensure service reliability.

Answer-45: A transaction in SOA ensures that a series of service calls are executed atomically, maintaining data consistency and integrity.

Answer-46: SOA enables multi-channel systems by providing reusable and consistent services that can be consumed by different front-end systems like mobile, web, and desktop applications.

Answer-47: A service endpoint is a URL or network address that identifies where a service is located and how it can be accessed.

Answer-48: Logging and monitoring are critical in SOA for tracking service performance, identifying issues, and ensuring system health.

Answer-49: A composite service is a service that aggregates multiple other services to perform a more complex operation or business process.

Answer-50: SOA divides the system into small, independent services that communicate over a network, while monolithic architecture is a single, tightly coupled application.