SOA Technology Concepts (S90-02A) Free Sample Questions

WS-ReliableMessaging is a protocol that enables messages to be delivered reliably between distributed applications in the presence of software component, system, or network failures. It defines mechanisms for guaranteed delivery, duplicate elimination, and message ordering. This directly addresses the requirement for guaranteed processing despite temporary service unavailability. WS-AtomicTransaction deals with distributed transactions, WS-Security handles message-level security, and WS-Policy describes service capabilities and constraints.

The Content-MD5 header (though older) and the more modern Digest header are specifically designed for end-to-end message integrity checks. The client computes a hash (e.g., MD5 or SHA-256) of the request body and sends it in one of these headers. The server then computes its own hash of the received body and compares it to the value in the header. If they don't match, it indicates data corruption, and the server can reject the request, typically with a 400 Bad Request status. ETag is for caching, and the others relate to content negotiation and size.

This statement is false. In the PaaS model, the cloud provider manages the underlying infrastructure, including the physical hardware, networking, and the operating system. The cloud consumer is responsible for deploying and managing their applications and data, but not the OS itself. The provider handles OS patching, updates, and maintenance. This abstraction is a key benefit of PaaS.

The xs:complexType element is the primary mechanism in XSD for defining custom data structures that can contain other elements, attributes, or a combination of both.

The xs:sequence element is a compositor used within an xs:complexType to specify that the child elements must appear in the defined order. It is a key part of defining the structure.

The primary violation is of the 'safety' property. Safe HTTP methods, like GET and HEAD, are defined as those that do not alter the state of the resource on the server. They are intended for read-only operations. Using GET to perform a destructive action like deleting an account is incorrect and dangerous, as crawlers, proxies, or pre-fetching mechanisms could inadvertently trigger the action. The correct method for deletion would be HTTP DELETE.

The One-Way MEP is ideal for this 'fire-and-forget' scenario. The service consumer sends a message to the service provider and does not expect a response. The interaction is complete once the message is sent. This decouples the client from the processing workflow, allowing for asynchronous communication. Request-Response would imply the client waits for a reply.

Rapid elasticity is the ability to provision and release computing resources elastically, in some cases automatically, to scale rapidly outward and inward commensurate with demand. This directly addresses the need to handle traffic spikes during sales and scale down during quiet periods, thereby optimizing performance and cost. Measured Service is related, as it enables the pay-per-use model that makes elasticity financially viable, but elasticity is the core capability for adjusting capacity.

Service agents are classified as passive or active. A passive agent, such as a monitoring or logging agent, observes and processes message content without modifying it. An active agent, such as a data transformation or validation agent, actively modifies the message content. Since this service only logs the message and does not alter it, it is a passive service agent.

The abstract definition in WSDL consists of , , and . These define the data types, the messages exchanged, and the operations, respectively, without specifying any protocol. The concrete definition consists of the (which specifies the protocol, like SOAP over HTTP) and (which specifies the endpoint address). Therefore, the and elements provide the concrete implementation details.

The enum keyword in JSON Schema is used to restrict a value to a fixed set of values. It must be an array with at least one element, where each element is unique. To meet the requirement, the schema would include "enum": ["DEBUG", "INFO", "WARN", "ERROR"]. The pattern keyword uses regular expressions, and const restricts the value to a single specific value, not a set.