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 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.
• 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. None of the above.
• D. 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.

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. None of the above.
• D. 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 .

Upon reviewing these requirements it becomes evident to you that the Orchestration
compound pattern will need to be applied. However, there are additional requirements that
need to be fulfilled. To build this service composition architecture, which patterns that is not
associated with the Orchestration compound pattern need to also be applied? (Be sure to
choose only those patterns that relate directly to the requirements described above.
Patterns associated with the Orchestration compound pattern include both the required or
core patterns that are part of the basic compound pattern and the optional patterns that can
extend the basic compound pattern.)

• A. Intermediate Routing
• B. Protocol Bridging
• C. Compensating Service Transaction
• D. Data Model Transformation
• E. State Repository
• F. Process Centralization
• G. Data Format Transformation
• H. Policy Centralization
• I. Atomic Service Transaction
• J. Event-Driven Messaging
• K. Redundant Implementation
• L. Reliable Messaging
• M. Service Data Replication

• A. The 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 .
• B. The 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 stateful.
  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.
• C. 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 so
  that a separate messaging queue is positioned between Service A and Service Consumer
• 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 .
  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.
• E. None of the above.