SOA Certified SOA Architect S90.09 Questions & Answers

• Question 11:

  You are told that in this service composition architecture, all four services are exchanging invoice-related data in an XML format. The services in Service Inventory A are standardized to use a specific XML schema for invoice data. Design standards were not applied to the service contracts used in Service Inventory B, which means that each service uses a different XML schema for the same kind of data. Database A and Database B can only accept data in the Comma Separated Value (CSV) format and therefore cannot accept XML formatted data. What steps can be taken to enable the planned data exchange between these four services?

  

  A. The Data Model Transformation pattern can be applied so that data model transformation logic is positioned between Service A and Service B, between Service A and Service C, and between Service C and Service D . The Data Format Transformation pattern can be applied so that data format transformation logic is positioned between the Service B logic and Database A and between the Service D logic and Database B.

  B. The Data Model Transformation pattern can be applied so that data model transformation logic is positioned between Service A and Service C and between Service C and Service D . The Data Format Transformation pattern can be applied so that data format transformation logic is positioned between

  the Service B logic and Database A and between the Service D logic and Database B.

  C. The Data Model Transformation pattern can be applied so that data model transformation logic is positioned between Service A and Service C . The Protocol Bridging pattern can be applied so that protocol bridging logic is positioned between Service A and Service B and between the Service C and Service D . The Data Format Transformation pattern can be applied so that data format transformation logic is positioned between the Service B logic and Database A and between the Service D logic and Database B.

  D. None of the above.

  Correct Answer: A

• Question 12:

  Service A sends a message to Service B (1). After Service B writes the message contents to Database A

  (2) it issues a response message back to Service A (3). Service A then sends a message to Service C (4). Upon receiving this message, Service C sends a message to Service D (5), which then writes the message contents to Database B (6) and issues a response message back to Service C (7).

  Service A and Service D are in Service Inventory A. Service B and Service C are in Service Inventory B.

  

  You are told that in this service composition architecture, all four services are exchanging invoice-related data in an XML format. However, the services in Service Inventory A are standardized to use a different XML schema for invoice data than the services in Service Inventory B. Also, Database A can only accept data in the Comma Separated Value (CSV) format and therefore cannot accept XML formatted data. Database B only accepts XML formatted data. However, it is a legacy database that uses a proprietary XML schema to represent invoice data that is different from the XML schema used by services in Service Inventory A or Service Inventory B. What steps can be taken to enable the planned data exchange between these four services?

  A. The Data Model Transformation pattern can be applied so that data model transformation logic is positioned between Service A and Service B, between Service C and Service D, and between the Service D logic and Database B. The Data Format Transformation pattern can be applied so that data format transformation logic is positioned between Service A and Service C, and between the Service B

  logic and Database A.

  B. The Data Model Transformation pattern can be applied so that data model transformation logic is positioned between the Service B logic and Database A. The Data Format Transformation pattern can be applied so that data format transformation logic is positioned between Service A and Service B, between Service A and Service C, between Service C and Service D, and between the Service D logic and Database B.

  C. The Data Model Transformation pattern can be applied so that data model transformation logic is positioned between Service A and Service B, between Service A and Service C, between Service C and Service D, and between the Service D logic and Database B. The Data Format Transformation pattern can be applied so that data format transformation logic is positioned between the Service B logic and Database A.

  D. None of the above.

  Correct Answer: C

• Question 13:

  Service Consumer A sends a message to Service A. There are currently three duplicate implementations of Service A (Implementation 1, Implementation 2, Implementation 3).

  The message sent by Service Consumer A is intercepted by Service Agent A (1), which determines at runtime which implementation of Service A to forward the message to.

  All three implementations of Service A reside on the same physical server.

  

  You are told that after Service A was deployed, each of its three implementations was claimed by a different IT department, which means each implementation of Service A has a different owner. You are informed that a new service capability will soon need to be added to Service A . This service capability will introduce new business logic specific to Service A as well as logic required to access a shared database. What steps can be taken to ensure that the service owners will each add the service capability in a consistent manner to their respective implementations of Service A?

  A. The Contract Centralization pattern can be applied so that when the new service capability is added, the Service A service contract will become the primary contact point for Service A . This will avoid Service Consumer A or any other potential service consumer from being designed to access the shared database directly. The Service Abstraction principle can be applied to further hide the implementation details so that Service Consumer A and other service consumers are unaware of the fact that the shared database is being accessed.

  B. The Legacy Wrapper pattern can be applied to establish a new wrapper utility service that will provide standardized data access service capabilities for the shared database. This will avoid Service A from having to access the shared database directly and will further support the application of the Service Loose Coupling principle between Service A and the new utility service. By abstracting the data access logic into the wrapper service, there is no need to add the new service capability to each implementation of Service A .

  C. The Standardized Service Contract principle is applied to ensure that the new service capability is consistently added to the service contract of each implementation and that it extends the existing Service A service contract in a manner that is compliant with current design standards. The Service Loose Coupling principle is applied to ensure that the new service capability remains decoupled from the underlying logic and implementation so that Service Consumer A does not become indirectly coupled to any new logic or to the shared database.

  D. None of the above.

  Correct Answer: C

• Question 14:

  Service Consumer A sends a message to Service A. There are currently three duplicate implementations of Service A (Implementation 1, Implementation 2, Implementation 3).

  The message sent by Service Consumer A is intercepted by Service Agent A (1), which determines at runtime which implementation of Service A to forward the message to.

  All three implementations of Service A reside on the same physical server.

  

  You are told that despite the fact that duplicate implementations of Service A exist, performance is still poor at times. Also, you are informed that a new service capability will soon need to be added to Service A that will introduce functionality that will require access to a shared database that is used by many other clients and applications in the IT enterprise. This is expected to add further performance demands on Service A . How can this service architecture be changed to improve performance in preparation for the addition of the new service capability?

  A. The Standardized Service Contract principle is applied to ensure that the new service capability extends the existing service contract in a manner that is compliant with current design standards. The Redundant Implementation pattern is applied to establish separate implementations of Service A that include duplicate databases with copies of the data that Service A requires from the shared database.

  B. The Service Autonomy principle is applied to further isolate the individual implementations of Service A by separating them onto different physical servers. When the new service capability is added, the Service Data Replication pattern is applied to give each implementation of Service A its own copy of the data it requires from the shared database.

  C. The Service Loose Coupling principle is applied together with the Standardized Service Contract principle to ensure that Service Consumer A is not indirectly coupled to the shared database after the new service capability is added to the service contract. The Legacy Wrapper pattern can be applied to establish a new utility service that will provide standardized data access service capabilities for the shared database.

  D. None of the above.

  Correct Answer: B

• Question 15:

  It has been confirmed that Policy A and Policy B are, in fact, the same policy and that the security credential check performed by Service Agent B also needs to be carried out on messages sent to Service

  B .

  

  How can this service composition architecture be changed to reduce the redundancy of policy content and fulfill the new security requirement?

  A. The Policy Centralization pattern can be applied so that Policy A and Policy B are combined into the same policy. The policy enforcement logic is removed from Service Agent C and Service Agent A is then used to enforce the policy for messages sent to Service A and Service B . Service Agent B can be used to perform the security credential check for Service A and Service B .

  B. The Policy Centralization pattern can be applied so that Policy A and Policy B are combined into the same policy. The Service Agent pattern is then applied to introduce a new service agent (called Service Agent D) which carries out the validation and enforcement of Policy A and Policy B. Service Agent B can be moved so that it performs the security credential check for Service B, but not for Service A .

  C. The Policy Centralization pattern can be applied so that Service Agent A is changed to enforce the policy for messages sent to Service A and Service B and to perform the security credential check for Service A and Service B .

  D. None of the above.

  Correct Answer: A

• Question 16:

  Service Consumer A sends a message to Service A. Before the message arrives with Service A, it is intercepted by Service Agent A (1). which checks the message for compliance to Policy A that is required by Service A. If the message fails compliance, Service Agent A will not allow it to proceed and will instead write the message contents to a log. If the message does comply to the policy, it continues to be transmitted toward Service A, but before it arrives it is intercepted by Service Agent B (2), which validates the security credentials in the message header. If the security credential validation fails, the message is rejected and a runtime exception is raised. If the security credentials are validated, the message is sent to Service A.

  Upon receiving the message, Service A retrieves a data value from a database and populates the message header with this data value (3) prior to forwarding the message to Service B. Before the message arrives at Service B. it is intercepted by Service Agent C (4) which checks the message for compliance with two policies: Policy B and Policy C. Policy B is identical to Policy A that was checked by Service Agent

  A. To check for compliance to Policy C. Service Agent C uses the data value added by Service A. If the message complies with both of the policies, it is forwarded to Service B (5), which stores the message contents in its own database.

  

  You are told that Policy B and Policy C have changed. Also, in order to carry out the compliance check of Policy C, Service Agent C will now require a new data value from the Service B database. How can this service composition architecture be changed to fulfill these new requirements?

  A. The Policy Centralization pattern can be applied so that only one service agent is used to enforce Policy A and Policy B. Service A is redesigned to first query Service B for the value required by Service Agent C to check the compliance of the updated Policy C. If the compliance check is successful, the message is sent to Service B .

  B. The Policy Centralization pattern can be applied so that only one service agent is used to enforce Policy A and Policy B. Service Consumer A is redesigned to first query Service B for the value required by Service Agent C. This way, Service Consumer A can include this value in the message header prior to sending the message to Service A .

  C. The Policy Centralization pattern can be applied so that only one service agent is used to enforce Policy A and Policy B. The policy enforcement logic for Policy C is removed from Service Agent C and instead embedded within the logic of Service B . This way, Service B can itself retrieve the value required to check compliance with Policy C. If the message received is not in compliance, Service B will reject it.

  D. None of the above.

  Correct Answer: D

• Question 17:

  Service A. Service B. and Service C are each designed to access the same shared legacy system. The service contracts for Service A, Service B, and Service C are standardized and decoupled from the underlying service logic. Service A and Service B are agnostic services that are frequently reused by different service compositions. Service C is a non- agnostic task service that requires access to the legacy system in order to retrieve business rules required for the service to make runtime decisions that determine its service composition logic. The legacy system uses a proprietary file format that Services A, B, and C need to convert to and from.

  

  Service A is an agnostic utility service that is used by other services to gain access to the legacy system. Services B and C were not designed to access the legacy system via Service A because the Service A service contract was derived from the legacy system API and is therefore not standardized and exhibits negative contract-to-implementation coupling. You are told that additional services need to be created, all of which need access to the legacy system. You are also told that the legacy system may be replaced in the near future. What steps can be taken to ensure that the replacement of the legacy system has a minimal impact on Services B and C and any future services that are designed to rely upon it?

  A. The Service Abstraction, Service Reusability, and Service Autonomy principles need to be applied in order to support the application of the Official Endpoint pattern to Service A . This would position Service A as the official utility service through which the legacy system can be accessed. Service B will need to be redesigned to access Service A instead of accessing the legacy

  system directly. Due to the dependency on business rules embedded within the legacy system the

  option of applying the Rules Centralization pattern is not available. Service C will therefore need to

  continue accessing the legacy system directly.

  B. The Standardized Service Contract and Service Loose Coupling principles can be applied in order to establish a standardized service contract for Service A that will eliminate its negative contract coupling. Service B will need to be redesigned to access Service A instead of accessing the legacy system directly. Due to the dependency on business rules embedded within the legacy system the option of applying the Rules Centralization pattern is not available. Service C will therefore need to continue accessing the legacy system directly.

  C. The Legacy Wrapper pattern can be applied together with the Standardized Service Contract principle in order to establish a standardized service contract for Service A that will eliminate its negative contract coupling. The Official Endpoint pattern can then be applied to position Service A as the official utility service through which the legacy system can be accessed. Services B and C will need to be redesigned to access Service A instead of accessing the legacy system directly.

  D. None of the above.

  Correct Answer: C

• Question 18:

  Service A. Service B. and Service C are each designed to access the same shared legacy system. The service contracts for Service A, Service B, and Service C are standardized and decoupled from the underlying service logic. Service A and Service B are agnostic services that are frequently reused by different service compositions. Service C is a non- agnostic task service that requires access to the legacy system in order to retrieve business rules required for the service to make runtime decisions that determine its service composition logic. The legacy system uses a proprietary file format that Services A, B, and C need to convert to and from.

  

  You are told that additional services need to be created, all of which need access to the legacy system. You are also told that the legacy system may be replaced in the near future. What steps can be taken to ensure that the replacement of the legacy system has a minimal impact on Services A, B, and C and any future services that are designed to rely upon it?

  A. The Legacy Wrapper pattern can be applied together with the Standardized Service Contract principle to position a standardized service contract between the legacy system and any services that require access to it. This effectively establishes a new utility service dedicated to the encapsulation of the legacy system. When the legacy system is replaced, the utility service can keep its standardized service contract. To build the utility service, the Data Format Transformation pattern is applied to convert between the proprietary legacy system file format and the XML format used in the standardized service contract.

  B. The Legacy Wrapper pattern can be applied together with the Official Endpoint pattern so that the Service A service contract is positioned as the sole access point for the legacy system. The Data Format Transformation pattern is applied to enable the conversion between the proprietary legacy system file format and the XML format used in the Service A service contract. Finally, the Contract Centralization pattern is applied so that Service A is forced to only access the legacy system via its

  published standardized service contract.

  C. The Legacy Wrapper pattern can be applied together with the Data Format Transformation pattern and the Standardized Service Contract principle in order to establish an intermediate layer of standardized transformation logic that is positioned between the legacy system and Services A, B, and C. This way, if the legacy system is replaced, the services will not be affected because of the abstraction established by the standardized transformation layer.

  D. None of the above.

  Correct Answer: A

• Question 19:

  The architecture for Service A displayed in the Figure shows how the core logic of Service A has expanded over time to connect to a database and a proprietary legacy system (1) and to support two separate service contracts (2) that are accessed by different service consumers.

  The service contracts are fully decoupled from the service logic. The service logic is therefore coupled to the service contracts and to the underlying implementation resources (the database and the legacy system).

  Service A currently has three service consumers. Service Consumer A and Service Consumer B access Service A's two service contracts (3, 4). Service Consumer C bypasses the service contracts and accesses the service logic directly (5).

  

  You are told that the database and legacy system that are currently being used by Service A are being replaced with different products. The two service contracts are completely decoupled from the core service logic, but there is still a concern that the introduction of the new products will cause the core service logic to behave differently than before. What steps can be taken to change the Service A architecture in preparation for the introduction of the new products so that the impact on Service Consumers A, B, and C is minimized?

  A. The Service Abstraction principle can be applied to hide the implementation details from the core service logic of Service A, thereby shielding this logic from changes to the implementation. In support of this, the Service Facade pattern can be applied to position Facade components between the core service logic and Service Consumers A and B. These Facade components will be designed to regulate the behavior of Service A . The Contract Centralization pattern can be applied to force Service Consumer C to access Service A via one of its existing service contracts.

  B. A third service contract can be added together with the application of the Contract Centralization pattern. This will force Service Consumer C to access Service A via the new service contract. The Service Facade pattern can be applied to position a Facade component between the new service contract and Service Consumer C in order to regulate the behavior of Service A . The Service Abstraction principle can be applied to hide the implementation details of Service A so that no future

  service consumers are designed to access any of Service A's underlying resources directly.

  C. The Service Facade pattern can be applied to position Facade components between the core service logic and the two service contracts. These Facade components will be designed to regulate the behavior of Service A . The Contract Centralization pattern can also be applied to force Service Consumer C to access Service A via one of its existing service contracts.

  D. None of the above.

  Correct Answer: C

• Question 20:

  Service A has become increasingly difficult to maintain. Its core service logic has become bloated and convoluted because it has been updated numerous times during which additional functionality was added to interact with the database and the legacy system and to support interaction with Service Consumers A and B (via the two service contracts) as well as interaction directly with Service Consumer C.

  

  What steps can be taken to solve these problems and to prevent them from happening again in the future?

  A. The Service Facade pattern can be applied to position a Facade component between the core service logic and the implementation resources (the database and the legacy system) and to also position a Facade component between the two service contracts and Service Consumers A and

  B. The Official Endpoint pattern can be applied to limit access to Service A to one of its two published service contracts. The Service Loose Coupling principle can be applied so that Service Consumer C does not negatively couple itself directly to the core service logic of Service A . B. The Service Facade pattern can be applied to position a Facade component between the core service logic and the implementation resources (the database and the legacy system) and to position a faade component between the core service logic and the two service contracts. The Contract Centralization pattern can be applied to limit access to Service A to one of its two published service contracts. The Service Abstraction principle can be applied to hide the implementation details of Service A from service consumers.

  C. The Service Faade pattern can be applied to position a Facade component between the core service logic and the two service contracts. The Contract Centralization pattern can be applied to limit access to Service A to one of its two published service contracts. The Service Loose Coupling principle can be applied so that Service Consumer C does not negatively couple itself directly to the core service logic of Service A .

  D. None of the above.

  Correct Answer: B