Arcitura Education S90.20 Exam Dumps

Service A provides a data retrieval capability that can be used by a range of service consumers, including Service Consumer A .In order to retrieve the necessary data, Service Consumer A first sends a request message to Service A (1). Service A then exchanges request and response messages with Service B (2, 3), Service C (4, 5), and Service D (6. 7). After receiving all three response messages from Services B .C .and D, Service A assembles the collected data into a response message that it returns to Service Consumer A (8). The owner of Service A charges service consumers for each usage of the data retrieval capability. Recently, the owner of Service Consumer A has complained that the data returned by Service A is incorrect, incomplete, and from invalid sources. As evidence, the Service Consumer A owner has presented the owner of Service A with sample messages containing the incorrect and incomplete contents. As a result, the Service Consumer A owner has refused to pay the usage fees. Subsequent to an internal investigation, the owner of Service A determines that the data returned by Service A is consistently correct and complete. There are suspicions that the Service Consumer A owner is altering the original messages and issuing these complaints fraudulently in order to avoid paying the usage fees. How can the owner of Service A prove that Service A is returning correct and complete data and that this data originated from the correct sources?

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Service A is a publically accessible service that provides free multimedia retrieval capabilities to a range of service consumers. To carry out this functionality, Service A is first invoked by Service Consumer A (1). Based on the nature of the request message received from Service Consumer A, Service A either invokes Service B or Service C .When Service B is invoked by Service A (2A) it retrieves data from publicly available sources (not shown) and responds with the requested data (3A). When Service C is invoked by Service A (2B) it retrieves data from proprietary sources within the IT enterprise (not shown) and responds with the requested data (3B). After receiving a response from Service B or Service C, Service A sends the retrieved data to Service Consumer A (4). Service B does not require service consumers to be authenticated, but Service C does require authentication of service consumers. The service contract for Service A therefore uses WS-Policy alternative policies in order to express the two different authentication requirements to Service Consumer A .When Service Consumer A sends a request message (1), Service A determines whether the request requires the involvement of Service C and then checks to ensure that the necessary security credentials were received as part of the message. If the credentials provided by Service Consumer A are verified. Service A creates a signed SAML assertion and sends it with the request message to Service C (2B) This authentication information is protected by public key encryption However, responses to Service Consumer A's request message (3B, 4) are not encrypted for performance reasons. Recently, the usage of Service C has noticeably declined. An investigation has revealed response messages issued by Service C (3B) have been repeatedly intercepted and accessed by unauthorized and malicious intermediaries. As a result, Service Consumer A has lost confidence in the use of Service A for the retrieval of proprietary data because it is being viewed as a security risk. This is especially troubling, because the owner of Service A had planned to start charging a fee for Service A's ability to provide proprietary data via the use of Service C .How can this service composition architecture be changed to address the security problem with minimal impact on runtime performance?

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Service A provides a data retrieval capability that can be used by a range of service consumers, including Service Consumer A, In order to retrieve the necessary data. Service Consumer A first sends a request message to Service A (1). Service A then exchanges request and response messages with Service B (2, 3). Service C (4, 5), and Service D (6. 7). After receiving all three response messages from Services B .C .and D, Service A assembles the collected data into a response message that it returns to Service Consumer A (8). The Service A data retrieval capability has been suffering from poor performance, which has reduced its usefulness to Service Consumer A .Upon studying the service composition architecture, it is determined that the performance problem can be partially attributed to redundant validation by service contracts for compliance to security policies. Services B and C have service contracts that contain the same two security policies. And, Service D has a service contract that contains a security policy that is also part of Service A's service contract. What changes can be made to the service contracts in order to improve the performance of the service composition while preserving the security policy compliance requirements?

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Service Consumer A sends a request message with a Username token to Service A (1). Service B authenticates the request by verifying the security credentials from the Username token with a shared identity store (2), To process Service Consumer A's request message. Service A must use Services B, C, and D .Each of these three services also requires the Username token (3. 6, 9) in order to authenticate Service Consumer A by using the same shared identity store (4, 7, 10). Upon each successful authentication, each of the three services (B, C, and D) issues a response message back to Service A (5, 8, 11). Upon receiving and processing the data in all three response messages, Service A sends its own response message to Service Consumer A (12). There are plans implement a single sign-on security mechanism in this service composition architecture. The service contracts for Services A, C, and D can be modified with minimal impact in order to provide support for the additional messaging requirements of the single sign-on mechanism. However, Service B's service contract is tightly coupled to its implementation and, as a result, this type of change to its service contract is not possible as it would require too many modifications to the underlying service implementation. Given the fact that Service B's service contract cannot be changed to support single sign-on, how can a single sign-on mechanism still be implemented across all services?

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Service A has two specific service consumers, Service Consumer A and Service Consumer B (1). Both service consumers are required to provide security credentials in order for Service A to perform authentication using an identity store (2). If a service consumer's request message is successfully authenticated, Service A processes the request by exchanging messages with Service B (3) and then Service C (4). With each of these message exchanges, Service A collects data necessary to perform a query against historical data stored in a proprietary legacy system. Service A's request to the legacy system must be authenticated (5). The legacy system only provides access control using a single account. If the request from Service A is permitted, it will be able to access all of the data stored in the legacy system. If the request is not permitted, none of the data stored in the legacy system can be accessed. Upon successfully retrieving the requested data (6), Service A generates a response message that is sent back to either Service Consumer A or B .The legacy system is also used independently by Service D without requiring any authentication. Furthermore, the legacy system has no auditing feature and therefore cannot record when data access from Service A or Service D occurs. If the legacy system encounters an error when processing a request, it generates descriptive error codes. This service composition architecture needs to be upgraded in order to fulfill the following new security requirements:

1. Service Consumers A and B have different access permissions and therefore, data received from the legacy system must be filtered prior to issuing a response message to one of these two service consumers.

2. Service Consumer A's request messages must be digitally signed, whereas request messages from Service Consumer B do not need to be digitally signed. Which of the following statements describes a solution that fulfills these requirements?

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