Cloud Computing Questions and Answers

Answer: A

Correct answer: on-demand self-service

NIST lists five: on-demand self-service, broad network access, resource pooling, rapid elasticity and measured service. Self-service comes first because it is the one that changes how the organisation works - capacity is obtained without raising a request or waiting on anyone, which is what turns provisioning from a project into a command. Unlimited capacity, guaranteed availability and free access are none of them, and no provider offers any of the three.

Answer: B

Correct answer: A-2, B-4, C-1, D-3

Each characteristic names a distinct property. Self-service is provisioning without human interaction on the provider’s side. Resource pooling is the multi-tenant sharing of a common pool, which is what makes the economics work. Rapid elasticity is scaling out and in quickly with demand. Measured service is the metering that makes pay-per-use possible - and without it, elasticity would have no commercial consequence.

Answer: C

Correct answer: unlimited free capacity

No provider offers unlimited capacity and none offers it free; quotas exist on every account and everything is metered. The other three are genuine NIST characteristics, and the remaining two are broad network access and on-demand self-service. What the cloud actually provides is the *appearance* of ample capacity, obtained without planning ahead.

Answer: D

Correct answer: scaling in as well as out automatically

Scalability is the capacity to grow to meet demand and says nothing about coming back down. Elasticity adds the automatic return: resources are released when the load falls, which is what makes the metered charge track the actual demand. Without the scaling in, an autoscaled system would ratchet upward to its peak and stay there, and the cost benefit would disappear.

Answer: A

Both are true and the reason gives the economics, and it is why automatic scale-in policies are as important as scale-out ones in a well designed deployment. Idle capacity still costs money. Scale-in policies deserve equal attention.

Answer: B

Correct answer: 1 and 2 only

Statements 1 and 2 give the two halves of the distinction: scalability is growth, and elasticity adds automatic contraction. Statement 3 denies that distinction. A system can be highly scalable and not elastic at all - a cluster that can be enlarged by hand meets the first definition and not the second.

Answer: C

Sharing is what makes the economics work, since idle capacity for one tenant serves another. Isolation between tenants is therefore a central security requirement. Pooling is what makes it economic. Idle capacity for one tenant serves another.

Answer: D

Both are true and the reason gives the necessity, and hypervisor and network isolation are the mechanisms by which it is normally achieved. A failure of isolation is among the most serious faults a cloud provider can suffer.

Answer: A

Correct answer: capital to operating expenditure

On-premises infrastructure is bought up front, depreciated and owned; cloud capacity is rented and expensed monthly. That shift is the financial argument for the cloud: no large outlay before the first user arrives, and cost that follows actual usage. It also has a consequence often overlooked - the spending becomes continuous and visible, so it needs governing rather than merely approving once.

Answer: B

Correct answer: 1 and 2 only

Statements 1 and 2 are correct, and the second is the more important: capacity no longer has to be bought for the annual peak and left idle the rest of the year. Statement 3 is a claim no analysis supports - a steady, predictable, heavily utilised workload is frequently cheaper on owned hardware, and the cloud’s advantage is greatest where demand is variable or uncertain.