最新的高品質 C90-03A 考試練習題庫

Cloud Provider X has deployed a virtualization environment in Cloud X comprised of Physical Server A hosting Virtual Servers A and B. Cloud Provider X implements Cloud Service A on Virtual Server A and makes it available to Cloud Service Consumer A, which interacts with Cloud Service A by sending and receiving messages (1, 2).
Cloud Provider Y has deployed a virtualization environment comprised of Physical Server B hosting Virtual Servers C and D. Virtual Server C is made available to Cloud Service Consumer B, which interacts with Virtual Server C (3,4) in order to prepare for the deployment of a new cloud service that will be used internally by Cloud Provider Y to process data obtained from Cloud Service A Cloud Consumer Z and Cloud Provider X belong to the same organization. Cloud Provider Y is a third-party organization. Which of the following statements provides a valid scenario that accurately describes the involvement of cloud deployment models, cloud delivery models, roles and/or boundaries? (Note that the correct answer represents one of multiple valid scenarios that can exist.)

• A. Cloud X is based on the private cloud deployment model. Cloud Service A is based on the SaaS delivery model. Cloud Y is based on the private cloud deployment model. Virtual Server C is being offered as part of theIaaS delivery model. A cloud resource administrator working for Cloud Consumer Z uses Cloud Service Consumer B to access Virtual Server C. Cloud Consumer Z is the cloud service owner of Cloud Service Cloud Consumer T s organizational boundary encompasses Cloud Service Consumers A and B. Cloud Consumer T s trust boundary encompasses Cloud Service Consumers A and B, Cloud Service A and Virtual Server C.
• B. Cloud X is based on the private cloud deployment model. Cloud Service A is based on the SaaS delivery model. Cloud Y is based on the public cloud deployment model. Virtual Server C is being offered as part of theIaaS delivery model. A cloud resource administrator working for Cloud Consumer Z uses Cloud Service Consumer B to access Virtual Server Cloud Consumer Z is the cloud service owner of Cloud Service A. Cloud Consumer Z's organizational boundary encompasses Cloud Service Consumers A and B. Cloud Consumer T s trust boundary encompasses Cloud Service Consumers A and B, Cloud Service A and Virtual Server
• C. Cloud X is based on the private cloud deployment model. Cloud Service A is based on theSaaS delivery model. Cloud Y isbased on the community cloud deployment model. VirtualServer C is being offered as part of theIaaS delivery model. A cloud resource administrator working for Cloud Consumer Z uses Cloud Service Consumer A to access Cloud Service A. Cloud Consumer T s organizational and trust boundaries encompass Cloud Service Consumers A and B, Cloud Service A and Virtual Server C.
• D. Cloud X is based on the private cloud deployment model. Cloud Service A is based on the SaaS delivery model. Cloud Y is based on the public cloud deployment model. Virtual Server C is being offered as part of theIaaS delivery model. A cloud resource administrator working for Cloud Consumer Z uses Cloud Service Consumer B to access Virtual Server C. Cloud Consumer Z' s trust boundary encompasses Cloud Service Consumers A and B, Cloud Service A and Virtual Server C. The organization that owns Cloud Consumer Z is the cloud service owner of Cloud Service A.

Cloud Provider Y owns Cloud Y, which provides a set of cloud services, virtual servers and one physical server. Cloud Services A and B are hosted on Virtual Server A, which is hosted by Physical Server A. Physical Server A also hosts Virtual Server B, which hosts redundant implementations of Cloud Services A and B for load balancing purposes. Cloud Service Consumer A is accessing Cloud Service A located on Virtual Server A. Cloud Service Consumer B is accessing Cloud Service B located on Virtual Server B. Cloud Service Consumers A and B are both owned by Cloud Consumer X.
Cloud Consumer X has recently complained that Cloud Services A and B have become less available than what is guaranteed in their service level agreements (SLAs). Cloud Provider Y launches an investigation that reveals that Virtual Servers A and B have been subjected to denial of service attacks. This is confirmed as the cause of the decline in the availability of Cloud Services A and B.

Which of the following statements describes a solution that can increase the availability of Cloud Services A and B?

• A. Cloud Provider Y can implement a cloud bursting system, whereby Cloud Service A on Virtual Server B automatically takes the place of Cloud Service A on Virtual Server A when that service fails. Similarly,Cloud Service B on Virtual Server A can then automatically take the place of Cloud Service B on Virtual Server A when that service fails.
• B. Cloud Provider Y can move Cloud Service B to Virtual Server A, thereby positioning Virtual Server B as a redundant fallback server used when Virtual Server A is successfully attacked. Similarly, Cloud Provider Yean move Cloud Service A to Virtual Server B, so that Virtual Server A acts as a redundant fallback server for when Virtual Server B is successfully attacked.
• C. Cloud Provider Y can implement the identity and access management mechanism to mitigate denial of service attacks and can further implement the failover system mechanism (by introducing a redundant physical server with redundant virtual servers) so that when an attack is successful on a given virtual server, a redundant virtual server can take its place.
• D. Cloud Provider Y can introduce a single sign-on mechanism for Virtual Server A to mitigate denial of service threats. The automated scaling listener can then be implemented on VirtualServer B in order to limit the number of instances of Cloud Services A and B. This will prevent Virtual Server B from overloading due to denial of service attacks.

A cloud consumer is interested in leasing cloud-based virtual servers. It compares the virtual servers offered by Cloud Provider X and Cloud Provider Y.
Cloud X (owned by Cloud Provider X) and Cloud Y (owned by Cloud Provider Y) both provide shared physical servers that host multiple virtual servers for other cloud consumers.
The virtual servers on Cloud X are accessed directly, whereas the virtual servers on Cloud Y are accessed via an automated scaling listener. On Cloud X, virtual servers are pre-configured to support a specific amount of concurrent cloud service consumers. When this threshold is exceeded, cloud service consumer requests are rejected. Due to the use of the automated scaling
listener, virtual servers on Cloud Y can provide a greater level of elasticity.

The hourly cost to the cloud consumer to use a virtual server on Cloud X is half that of the cost to use a virtual server on Cloud Y.
Within a one month period, Cloud Provider X bases its hourly charge on the maximum number of virtual servers used. Within a one month period, Cloud Provider Y bases its hourly charges on actual virtual server usage. Cloud Provider Y charges $20 for each hour that a cloud consumer uses a virtual server.
The cloud consumer predicts its monthly usage requirements to be as follows: The cloud consumer is required to choose the cloud provider with the lowest on-going cost, based on its predicted usage. Which of the following statements accurately calculates the on-going usage costs of Cloud Providers X and Y and correctly states the cloud provider that the cloud consumer must choose?

• A. The total usage duration is (20 + 30 + 50) x 12 hours = 1,200 hours.
  The actual usage is (20 X 3) + (30 X4) + (50 X 5) server hours = 430 server hours.
  The cost of using virtual servers from Cloud ProviderXis12X5X$10 = $600.
  The cost of using virtual servers from Cloud Provider Y is 430 X $20 = $8,600.
  The cloud consumer must therefore choose Cloud Provider X.
• B. The total usage duration is (20 + 30 + 50) hours = 100 hours.
  The actual usage is (20X3)+ (30X4) + (50X5) hours =430 hours.
  The cost of using virtual servers from Cloud Provider Xis100X5X$10 = $5,000.
  The cost of using virtual servers from Cloud Provider Y is 430 X $20 = $8,600.
  The cloud consumer must therefore choose Cloud Provider X.
• C. The total usage duration is (3 x 20) + (4 x 30) + (5 x 50) hours = 430 hours.
  The actual usage is (20 + 30 + 50) hours = 100 hours.
  The cost of using virtual servers from Cloud Provider X is (430 X $10) = $4,300.
  The cost of using virtual servers from Cloud Provider Y is (100 X $20) = $2,000.
  The cloud consumer must therefore choose Cloud Provider Y.
• D. The total usage duration is (20 + 30 + 50) hours = 100 hours.
  The actual usage is (20 + 30 + 50) X 5 server hours = 500 server hours.
  The cost of using virtual servers from Cloud Provider X is (500 X 5 X$10) = $25,000.
  The cost of using virtual servers from Cloud Provider Y is (500 X $20) = $10,600.
  The cloud consumer must therefore choose Cloud Provider Y.