SOA S90.09 Exam Questions

Question 6 of 40

Service A is a utility service that provides generic data access logic to a database that contains data that is periodically replicated from a shared database (1).
Because the Standardized Service Contract principle was applied to the design of Service A, its service contract has been fully standardized.
Service A is being accessed by three service consumers. Service Consumer A accesses a component that is part of the Service A implementation by invoking it directly (2). Service Consumer B invokes Service A by accessing its service contract (3). Service Consumer C directly accesses the replicated database that is part of the Service A implementation (4).
Exam S90.09: Question 6 - Image 1

You've been told that the reason Service Consumers A and C bypass the published Service A service contract is because, for security reasons, they are not allowed to access a subset of the operations in the WSDL definition that expresses the service contract. How can the Service A architecture be changed to enforce these security restrictions while avoiding negative forms of coupling?

A.

The Contract Centralization pattern can be applied to force all service consumers to access the Service A architecture via its published service contract. This will prevent negative forms of coupling that could lead to problems when the database is replaced. The Service Abstraction principle can then be applied to hide underlying service architecture details so that future service consumers cannot be designed to access any part of the underlying service implementation.

B.

The Contract Centralization pattern can be applied to force service consumers to access the Service A architecture via its published service contract only. The Service Loose Coupling principle can then be applied to ensure that the centralized service contract does not contain any content that is dependent on or derived from the underlying service implementation.

C.

The Concurrent Contracts pattern can be applied to Service A in order to establish one or more alternative service contracts. This allows service consumers with different levels of security clearance to continue accessing the service logic via its published service contracts.

D.

None of the above.

Correct Answer: C

Question 7 of 40

Service A is a task service that is required to carry out a series of updates to a set of databases in order to complete a task. To perform the database updates
Service A must interact with three other services, each of which provides standardized data access capabilities.
Service A sends its first update request message to Service B (1), which then responds with a message containing a success or failure code (2). Service A then sends its second update request message to Service C (3), which also responds with a message containing a success or failure code (4). Finally, Service A sends a request message to Service D (5), which responds with its own message containing a success or failure code (6).
Exam S90.09: Question 7 - Image 1

You've been given a requirement that all database updates must either be completed successfully or not at all. This means that if any of the three response messages received by Service A contain a failure code, all of the updates carried out until that point must be reversed. Note that if Service A does not receive a response message back from Services B, C, or D, it must assume that a failure has occurred. How can this service composition architecture be changed to fulfill these requirements?

A.

The Reliable Messaging pattern can be applied to guarantee the delivery of positive or negative acknowledgements. This way, Service A will always be informed of whether a failure condition has occurred with any of the database updates performed by Services B, C, and D. Furthermore, the Service Loose Coupling principle can be applied to ensure that the request and response messages exchanged by the services do not contain any implementation details that would indirectly couple Service A to any of the databases.

B.

The Atomic Service Transaction pattern can be applied individually to Services B, C, and D so that each of these services performs its own database update within the scope of an atomic transaction. If anyone update fails, that change can be rolled back on that database. Furthermore, the Service Loose Coupling principle can be applied to ensure that Service A is kept out of the scope of the atomic transaction so that it is not negatively coupled to the proprietary database technologies that are required to enable the atomic transaction functionality.

C.

The Compensating Service Transaction can be applied to Service A so that when any one response message containing a failure code is received by Service A, it can invoke exception handling logic that will log the failed database updates. The Service Loose Coupling principle can be further applied to ensure that Services B, C, or D are not indirectly coupled to the exception handling logic, especially if Service A requires additional access to Services B, C, or D in order to collect more information for logging purposes.

D.

None of the above.

Correct Answer: D

Question 8 of 40

Service A is a task service that is required to carry out a series of updates to a set of databases in order to complete a task. To perform the database updates
Service A must interact with three other services, each of which provides standardized data access capabilities.
Service A sends its first update request message to Service B (1), which then responds with a message containing a success or failure code (2). Service A then sends its second update request message to Service C (3), which also responds with a message containing a success or failure code (4). Finally, Service A sends a request message to Service D (5), which responds with its own message containing a success or failure code (6).
Exam S90.09: Question 8 - Image 1

You've been asked to change this service composition architecture in order to fulfill a set of new requirements: First, if the database update performed by Service
B fails, then it must be logged by Service A. Secondly, if the database update performed by Service C fails, then a notification e-mail must be sent out to a human administrator. Third, if the database update performed by either Service C or Service D fails, then both of these updates must be reversed so that the respective databases are restored back to their original states. What steps can be taken to fulfill these requirements?

A.

Service A is updated to perform a logging routine when Service A receives a response message from Service B containing a failure code. Service A is further updated to send an e-mail notification to a human administrator if Service A receives a response message from Service C containing a failure code. The Atomic Service Transaction pattern is applied so that Services A, C, and D are encompassed in the scope of a transaction that will guarantee that if the database updates performed by either Service C or Service D fails, then both updates will be rolled back.

B.

The Compensating Service Transaction pattern is applied to Service B so that it invokes exception handling logic that logs failed database updates before responding with a failure code back to Service A . Similarly, the Compensating Service Transaction pattern is applied to Service C so that it issues an e-mail notification to a human administrator when a database update fails. The Atomic Service Transaction pattern is applied so that Services A, C, and D are encompassed in the scope of a transaction that will guarantee that if the database updates performed by either Service C or Service D fails, then both updates will be rolled back. The Service Autonomy principle is further applied to Service A to ensure that it remains consistently available to carry out this sequence of actions.

C.

The Atomic Service Transaction pattern is applied so that Services A, C, and D are encompassed in the scope of a transaction that will guarantee that if the database updates performed by either Service C or Service D fails, then both updates will be rolled back. The Compensating Service Transaction pattern is then applied to all services so that the scope of the compensating transaction includes the scope of the atomic transaction. The compensating exception logic that is added to Service D automatically invokes Service B to log the failure condition and Service C to issue the e-mail notification to the human administrator. This way, it is guaranteed that the compensating logic is always executed together with the atomic transaction logic.

D.

None of the above.

Correct Answer: A

Question 9 of 40

Service A is a task service that sends Service B a message (2) requesting that Service B return data back to Service A in a response message (3). Depending on the response received. Service A may be required to send a message to Service C (4) for which it requires no response.
Before it contacts Service B, Service A must first retrieve a list of code values from its own database (1) and then place this data into its own memory. If it turns out that it must send a message to Service C, then Service A must combine the data it receives from Service B with the data from the code value list in order to create the message it sends to Service C. If Service A is not required to invoke Service C, it can complete its task by discarding the code values.
Service A and Service C reside in Service Inventory A. Service B resides in Service Inventory B.
Exam S90.09: Question 9 - Image 1

You are told that the services in Service Inventory A are all SOAP-based Web services designed to exchange SOAP 1.1 messages and the services in Service
Inventory B are SOAP-based Web services designed to exchange SOAP 1.2 messages. Therefore, Service A and Service B cannot currently communicate.
Furthermore, you are told that Service B needs to access a shared database in order to retrieve the data required by Service A. The response time of the database can sometimes be lengthy, which would cause Service A to consume too much resources while it is waiting and keeping the code values in memory.
How can this service composition architecture be changed to avoid these problems?

A.

The Protocol Bridging pattern can be applied by establishing an intermediate processing layer between Service A and Service B that can convert SOAP 1.1 messages to SOAP 1.2 messages and vice versa. The Service Data Replication pattern can be applied to Service B so that it is given a dedicated database with its own copy of the data it needs to access. The Service Normalization pattern can then be applied to ensure that the data within the replicated database is normalized with the shared database it is receiving replicated data from.

B.

The Protocol Bridging pattern can be applied by establishing an intermediate processing layer between Service A and Service B that can convert SOAP 1.1 messages to SOAP 1.2 messages and vice versa. The Service Statelessness principle can be applied with the help of the State Repository pattern so that Service A can write the code value data to a state database while it is waiting for Service B to respond.

C.

The Protocol Bridging pattern can be applied by establishing an intermediate processing layer between Service A and Service B that can convert SOAP 1.1 messages to SOAP 1.2 messages and vice versa. The Intermediate Routing pattern can be applied to dynamically determine whether Service A should send a message to Service C. The Service Autonomy principle can be applied to Service A to further increase its behavioral predictability by reducing the amount of memory it is required to consume.

D.

None of the above.

Correct Answer: B

Question 10 of 40

Service A is a task service that sends Service B a message (2) requesting that Service B return data back to Service A in a response message (3). Depending on the response received. Service A may be required to send a message to Service C (4) for which it requires no response.
Before it contacts Service B, Service A must first retrieve a list of code values from its own database (1) and then place this data into its own memory. If it turns out that it must send a message to Service C, then Service A must combine the data it receives from Service B with the data from the code value list in order to create the message it sends to Service C. If Service A is not required to invoke Service C, it can complete its task by discarding the code values.
Service A and Service C reside in Service Inventory A. Service B resides in Service Inventory B.
Exam S90.09: Question 10 - Image 1

You are told that the services in Service Inventory A were designed with service contracts based on different design standards than the services in Service
Inventory B. As a result, Service A and Service B use different data models to represent the data they need to exchange. Therefore, Service A and Service B cannot currently communicate. Furthermore, Service C is an agnostic service that is heavily accessed by many concurrent service consumers. Service C frequently reaches its usage thresholds during which it is not available and messages sent to it are not received. How can this service composition architecture be changed to avoid these problems?

A.

The Data Model Transformation pattern can be applied by establishing an intermediate processing layer between Service A and Service B that can transform a message from one data model to another at runtime. The Intermediate Routing and Service Agent patterns can be applied so that when Service B sends a response message, a service agent can intercept the message and, based on its contents, either forward the message to Service A or route the message to Service C . The Service Autonomy principle can be further applied to Service C together with the Redundant Implementation pattern to help establish a more reliable and scalable service architecture.

B.

The Data Model Transformation pattern can be applied by establishing an intermediate processing layer between Service A and Service B that can transform a message from one data model to another at runtime. The Asynchronous Queuing pattern can be applied to establish an intermediate queue between Service A and Service C so that when Service A needs to send a message to Service C, the queue will store the message and retransmit it to Service C until it is successfully delivered. The Service Autonomy principle can be further applied to Service C together with the Redundant Implementation pattern to help establish a more reliable and scalable service architecture.

C.

The Data Model Transformation pattern can be applied by establishing an intermediate processing layer between Service A and Service B that can transform a message from one data model to another at runtime. The Intermediate Routing and Service Agent patterns can be applied so that when Service B sends a response message, a service agent can intercept the message and, based on its contents, either forward the message to Service A or route the message to Service C . The Service Statelessness principle can be applied with the help of the State Repository pattern so that Service A can write the code value data to a state database while it is waiting for Service B to respond.

D.

None of the above.

Correct Answer: B