Task 4.1: Compare AWS pricing models.

• AOn-Demand Instances

  Incorrect

  On-Demand has a static hourly price. Spare capacity is sold for less than that price, and these jobs can use it.

• BReserved Instances with a three-year term

  Incorrect

  Reserved Instances are a discount for a one- or three-year commitment to a matching instance, billed whether or not you use it — a poor fit for jobs that run only some of the time.

• CSpot Instances

  Correct

  Spot Instances use spare EC2 capacity for less than the On-Demand price. They suit flexible work that can be interrupted, such as data analysis and batch jobs.

• DOn-Demand Capacity Reservations

  Incorrect

  A Capacity Reservation guarantees capacity in an Availability Zone but gives no billing discount of its own.

Interruptible, flexible work is exactly what spare capacity is sold for: the team trades a guarantee it does not need for a steep discount.

• ASavings Plans

  Correct

  Savings Plans lower prices compared with On-Demand in exchange for a commitment to a consistent amount of usage, measured in dollars per hour, for one or three years.

• BSpot Instances

  Incorrect

  Spot Instances are cheaper, but Amazon EC2 can interrupt them when it needs the capacity back — not acceptable for this server.

• COn-Demand Capacity Reservations

  Incorrect

  Capacity Reservations reserve capacity in an Availability Zone but provide no billing discount.

• DReserved Instances

  Correct

  Reserved Instances give a significant discount compared with On-Demand for a one- or three-year commitment to an instance configuration.

• EAWS Pricing Calculator

  Incorrect

  The Pricing Calculator estimates costs for planning. It does not change what you are billed.

Steady, always-on usage that will last for years is what commitment discounts are for. Savings Plans are the more flexible of the two.

• ADedicated Instances

  Incorrect

  Dedicated Instances run on hardware dedicated to one customer account, but they give no visibility of sockets, cores or host ID, and support bring your own license only partially.

• BDedicated Hosts

  Correct

  A Dedicated Host is a physical server fully dedicated to you. It shows the number of sockets and physical cores and supports existing per-socket, per-core or per-VM licenses.

• CSpot Instances

  Incorrect

  Spot Instances use spare EC2 capacity at a discount and can be interrupted. They give no control over, or visibility of, the physical server.

• DSavings Plans

  Incorrect

  Savings Plans are a billing discount for a usage commitment. They do not change which hardware your instances run on.

Server-bound licensing is the classic reason for Dedicated Hosts: you get the physical server, and with it the core and socket counts your license terms ask for.

• AData sent from its EC2 instances out to the internet

  Incorrect

  Data transfer from AWS to the internet is charged, and is usually the largest data transfer item on a bill.

• BData sent from one AWS Region to another

  Incorrect

  Transfer between Regions is charged on the outbound side, at the source Region.

• CData sent into AWS from the internet

  Correct

  There is no charge for data transfer from the internet to AWS.

• DData sent between Availability Zones in the same Region

  Incorrect

  Transfer between Availability Zones in a Region is metered, in both directions for each resource, although some services do not charge for it.

As a rule of thumb, data coming in is free, and data going out — to the internet, to another Region, or across zones — is what costs money.

• AStandard Reserved Instances

  Incorrect

  Standard Reserved Instances give the biggest discount but can only be modified; they cannot be exchanged for different instance attributes.

• BConvertible Reserved Instances

  Correct

  Convertible Reserved Instances give a lower discount than Standard ones, but can be exchanged for another Convertible Reserved Instance with different instance attributes.

• CSpot Instances

  Incorrect

  Spot Instances are discounted spare capacity that can be interrupted — not a reservation for a three-year workload.

• DOn-Demand Capacity Reservations

  Incorrect

  A Capacity Reservation reserves capacity in an Availability Zone but gives no billing discount on its own.

Within Reserved Instances, the trade-off is discount against flexibility: Standard saves more, Convertible lets you change course.