Arcitura Education S90.09 SOA Design & Architecture Lab Exam Practice Test

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Total 40 questions

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Question 1

Answer : C, L

Question 2

Answer : H, L, M

Question 3

You are an architect with a project team building services for Service Inventory A . You are told that no SLAs for Service B and Service C are available. You cannot determine how available these services will be, but it has been confirmed that both of these services support atomic transactions and the issuance of positive and negative acknowledgements. However, you also find out that the services in Service Inventory B use different data models than the services in Service Inventory A . Furthermore, recent testing results have shown that the performance of Service D is steady and reliable. However, Service D uses a different transport protocol than the services in Service Inventory A . The response time of Service A is not a primary concern, but Service Consumer A does need to be able to issue request messages to Service A 24 hours a day without disruption. What steps can be taken to fulfill these requirements?

AThe Event-Driven Messaging pattern is applied so that a subscriber-publisher relationship is established between Service Consumer A and Service A . This gives Service A the flexibility to provide its response to Service Consumer A whenever it is able to collect the three data values without having to require that Service Consumer A remain state ful. The Asynchronous Queuing pattern is applied so that a central messaging queue is positioned between Service A and Service B and between Service A and Service C . The Data Model Transformation and Protocol Bridging patterns are applied to enable communication between Service A and Service B and between Service A and Service C . The Service Autonomy principle is further applied to Service A in order to improve its overall runtime behavioral predictability.

BThe Reliable Messaging pattern is applied so that a system of acknowledgements is established between Service Consumer A and Service A . This gives Service A the flexibility to provide Service Consumer A with acknowledgements that indicate that the processing steps that are occurring between Service A and Service B, Service C, and Service D are progressing. The Asynchronous Queuing pattern is applied so that a central messaging queue is positioned between Service A and Service B and between Service A and Service C and between Service A and Service D . The Redundant Implementation pattern is applied so that a copy of Service D is brought in-Upon reviewing these requirements it becomes D with a standardized service contract that is in compliance with the design standards used in Service Inventory A .

CThe Asynchronous Queuing pattern is applied so that a central messaging queue is positioned between Service A and Service B and between Service A and Service C and between Service A and Service D and so that a separate messaging queue is positioned between Service A and Service Consumer A . The Data Model Transformation pattern is applied to enable communication between Service A and Service B and between Service A and Service C . The Protocol Bridging pattern is applied to enable communication between Service A and Service D .

DNone of the above.

Answer : C

Question 4

Service Consumer A invokes Service A (1). The logic within Service A is required to retrieve three independent data values from Services B, C, and D and to then return these data values back to Service Consumer A . To accomplish this, Service A begins by sending a request message to Service B (2). After receiving a response message with the first data value from Service B, Service A sends a request message to Service C (3). After it receives a response message with the second data value from Service C, Service A then sends a request message to Service D (4). Upon receiving a response message with the third data value from Service D . Service A finally sends its own response message (containing all three collected data values) back to Service Consumer A . Service Consumer A and Service A reside in Service Inventory A . Service B and Service C reside in Service Inventory B . Service D is a public service that can be openly accessed via the World Wide Web. The service is also available for purchase so that it can be deployed independently within IT enterprises. Due to the rigorous application of the Service Abstraction principle within Service Inventory B, the only information that is made available about Service B and Service C are the published service contracts. For Service D, the service contract plus a Service Level Agreement (SLA) are made available. The SLA indicates that Service D has a planned outage every night from 11 PM to midnight.

You are an architect with a project team building services for Service Inventory A . You are told that the owners of Service Inventory A and Service Inventory B are not generally cooperative or communicative. Cross-inventory service composition is tolerated, but not directly supported. As a result, no SLAs for Service B and Service C are available and you have no knowledge about how available these services are. Based on the service contracts you can determine that the services in Service Inventory B use different data models and a different transport protocol than the services in Service Inventory A . Furthermore, recent testing results have shown that the performance of Service D is highly unpredictable due to the heavy amount of concurrent access it receives from service consumers from other organizations. You are also told that there is a concern about how long Service Consumer A will need to remain stateful while waiting for a response from Service A . What steps can be taken to solve these problems?

AThe Event-Driven Messaging pattern is applied so that a subscriber-publisher relationship is established between Service Consumer A and Service A . This gives Service A the flexibility to provide its response to Service Consumer A whenever it is able to collect the three data values without having to require that Service Consumer A remain state ful. The Asynchronous Queuing pattern is applied so that a central messaging queue is positioned between Service A and Service B and between Service A and Service C . The Data Model Transformation and Protocol Bridging patterns are applied to enable communication between Service A and Service B and between Service A and Service C . The Redundant Implementation pattern is applied so that a copy of Service D is brought in-house and made part of Service Inventory A .

BThe Asynchronous Queuing pattern is applied so that a central messaging queue is positioned between Service A and Service B and between Service A and Service C and so that a separate messaging queue is positioned between Service A and Service Consumer A . The Data Model Transformation and Protocol Bridging patterns are applied to enable communication between Service A and Service B and between Service A and Service C . The Redundant Implementation pattern is applied so that a copy of Service D is brought in-house for fail-over purposes. The Legacy Wrapper pattern is further applied to wrap Service D with a standardized service contract that is in compliance with the design standards used in Service Inventory A . This wrapper utility service first attempts to access the external service, but if that service is unavailable it will access the redundant internal service instead.

CThe Reliable Messaging pattern is applied so that a system of acknowledgements is established between Service Consumer A and Service A . This gives Service A the flexibility to provide Service Consumer A with acknowledgements that indicate that the processing steps that are occurring between Service A and Service B, Service C, and Service D are progressing. The Asynchronous Queuing pattern is applied so that a central messaging queue is positioned between Service A and Service B and between Service A and Service C and between Service A and Service D . The Data Model Transformation and Protocol Bridging patterns are applied to enable communication between Service A and Service B and between Service A and Service C .

DNone of the above.

Answer : B

Question 5

Service Consumer A sends a message with a business document to Service A (1), which writes the business document to Database A (2). Service A then forwards the business document to Service B (3), which writes the business document to Database B (4). Service B then responds to Service A with a message containing a failure or success code (5) after which Service A responds to Service Consumer A with a message containing a failure or success code (6). Upon receiving the message, Service Consumer A updates a log table in Database B (7). The log entry is comprised of the entire business document. Database A is dedicated to the Service A service architecture and Database B is a shared database.

There are two problems with this service composition architecture that you are asked to address: First, both Service Consumer A and Service B need to transform the business document data from an XML format to a proprietary Comma Separated Value (CSV) in order to write the data to Database B . This has led to redundant data format transformation logic that has been difficult to keep in synch when Database B changes. Secondly, Service A is an entity service that is being reused by several other service compositions. It has lately developed reliability problems that have caused the service to become unavailable for extended periods. What steps can be taken to solve these problems?

AThe Legacy Wrapper pattern can be applied so that data access to Database B is separated into a new wrapper utility service. This way, the Data Format Transformation pattern only needs to be applied within the logic of this new service which will expose a standardized contract that both Service Consumer A and Service B can access. The Asynchronous Queuing pattern can be applied so that messaging queues are established between Service Consumer A and Service A and between Service A and Service B . The Service Autonomy principle can be further applied to Service A in order to establish a more isolated and reliable surrounding infrastructure.

BThe Legacy Wrapper pattern can be applied so that data access to Database B is separated into a new wrapper utility service. This way, the Data Format Transformation pattern only needs to be applied within the logic of this new service which will expose a standardized contract that both Service Consumer A and Service B can access. The Reliable Messaging pattern can be applied so that acknowledgements are passed between Service Consumer A and Service A and between Service A and Service B . The Service Compos ability principle can be further applied to Service A in order to optimize its service architecture for improved participation in multiple service compositions.

CThe service composition can be redesigned with the application of the Contract Centralization pattern so that instead of writing the business document to Database B, Service Consumer A sends the business document to Service B instead. This way, Service B would provide the only location where data format transformation logic for Database B needs to be carried out, which further supports the application of the Service Reusability principle. The Reliable Messaging pattern can be applied so that acknowledgements are passed between Service Consumer A and Service A and between Service A and Service B . The Service Compos ability principle can be further applied to Service A in order to optimize its service architecture for improved participation in multiple service compositions.

DNone of the above.

Answer : A

Question 6

You are told that the database updates performed by Service A and Service B must be either both successful or they cannot happen at all. The database update performed by Service Consumer A must happen after it is given the outcome of the database updates performed by Service A and Service B . Given that Service Consumer A must also update Database B as part of this service composition architecture, how is it possible to fulfill these requirements?

AThe State Repository pattern can be applied so that Service A writes the business document data to a separate state database until it receives a response message from Service B . If the response message contains a success code, Service A writes the business document to Database A . If the response contains a failure code, Service A discards the data that was written to the state database.

BThe Service Data Replication pattern can be applied to Service Consumer A and Service B so that separate dedicated databases can be established allowing Service Consumer A to make updates independently of Service B . Service A is simply redesigned to not write the business document to Database A until after it receives a message containing a success code from Service B .

CThe Atomic Service Transaction pattern can be applied to encompass Service A, Service B and Service Consumer A . This will guarantee that all of the actions performed by the service composition participants will either be successful or will be rolled back if anyone is not successful.

DNone of the above.

Answer : D

Question 7

Service Consumer A sends Service A a message containing a business document (1). The business document is received by Component A, which keeps the business document in memory and forwards a copy to Component B (3). Component B first writes portions of the business document to Database A (4). Component B writes the entire business document to Database B and then uses some of the data values from the business document as query parameters to retrieve new data from Database B (5). Next, Component B returns the new data back to Component A (6), which merges it together with the original business document it has been keeping in memory and then writes the combined data to Database C (7). The Service A service capability invoked by Service Consumer A requires a synchronous request-response data exchange. Therefore, based on the outcome of the last database update, Service A returns a message with a success or failure code back to Service Consumer A (8). Databases A and B are shared and Database C is dedicated to the Service A service architecture.

There are several problems with this architecture: The business document that Component A is required to keep in memory (while it waits for Component B to complete its processing) can be very large. Especially when Service A is concurrently invoked by multiple service consumers, the amount of runtime resources it uses to keep this data in memory can decrease the overall performance of all service instances. Additionally, because Database A is a shared database that sometimes takes a long time to respond to Component B, Service A can take a long time to respond back to Service Consumer A . Currently, Service Consumer A will wait for a response for up to 30 seconds after which it will assume the request to Service A has failed and any subsequent response messages from Service A will be rejected. What steps can be taken to solve these problems?

AThe Service Statelessness principle can be applied together with the State Repository pattern in order to extend Database C so that it also becomes a state database allowing Component A to temporarily defer the business document data while it waits for a response from Component B . The Service Autonomy principle is applied together with the Legacy Wrapper pattern to isolate Database A so that it is encapsulated by a separate wrapper utility service. The Compensating Service Transaction pattern is applied so that if the response time of Service A exceeds 30 seconds, a notification is sent to a human administrator to raise awareness of the fact that the eventual response of Service A will be rejected by Service Consumer A .

BThe Service Statelessness principle can be applied together with the State Repository pattern in order to establish a state database that Component A can defer the business document data to while it waits for a response from Component B . The Service Autonomy principle can be applied together with the Service Data Replication pattern to establish a dedicated replicated database for Component B to access instead of the shared Database A . The Asynchronous Queuing pattern can be applied to establish a messaging queue between Service Consumer A and Service A so that Service Consumer A does not need to remain stateful while it waits for a response from Service A .

CThe Service Statelessness principle can be applied together with the State Repository pattern in order to establish a state database that Component A can defer the business document data to while it waits for a response from Component B . The Service Autonomy principle can be applied together with Service Abstraction principle, the Legacy Wrapper pattern, and the Service Facade pattern in order to isolate Database A so that it is encapsulated by a separate wrapper utility service and to hide the Database A implementation from Service A and to position a Facade component between Component B and the new wrapper service. This Facade component will be responsible for compensating the unpredictable behavior of Database A .

DNone of the above.

Answer : B