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6. In my solution to the Alarm Monitoring System, I didn't use the internet for communication between send the alarm messages from the home to the Alarm Company. Which of the following reasons contributed to that decision?:
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a. Security: if I used the internet, I would have to implement defenses against someone prevent the message for reaching its destination or intercepting the message & pass on false data ("A Man in the Middle Attack"), which would make the system more complex and expensive.
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Yes
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No
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b. Availability: Internet is more like to be unavailable then a phone line
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Yes
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No
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c. Predictability: I cannot predict how long it will take a message to reach the Central Monitoring System.
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Yes
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No
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d. Sending a message over the internet would be less scalable the using phone lines
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Yes
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No
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e. If would be harder to add RT streaming video over the internet than a phone line
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Yes
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No
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7. In my Solution to the Alarm Monitoring System that I gave you, I Said That The In-House Monitor Software Had 3 Subcomponents: A Control Loop For Monitoring Windows & Doors, A Control Loop For Controlling Doors, And A Component For Interacting With A User On A Control Panel. The User Monitor Has Subcomponents That Implement The Model-View-Controller Pattern). Even though the CPU it runs on is dual core. Assuming the schedule analysis tools says that each component/subcomponents will meet its deadline, this design works relatively easily because the deadline for turn on the alarm if a doors with a Control Pad nearby sensors is an exact multiple of the deadline for turning on the alarm for windows & doors without near-by Control-Pad. Are the following statements True or False
(Note both the In-Home Monitor Component, and its User Monitor Component are examples of the Façade Pattern, where all the work they appear to do is actually delegated to subcomponents.)
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Yes
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No
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a. It would be better to have 1 component that does all the work down by the subcomponents in one place, because it could be executed on a single core CPU.
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True
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False
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b. It would be better to have 4 components, replacing the single sensor monitoring component with a component to monitor the doors with a near-by control pad, and a component to monitor windows and doors without near-by control pads, as long as deadlines could still be met, since that would allow greater flexibility because the deadline for each component would be more flexible (i.e. one deadline would not have to be a multiple of the other or a common denominator for the analysis too work.
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True
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False
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c. By extending the logic in (b), it would be better to have 5 components, where to component to monitor windows and doors without near-by control pads, would be replaced by a component to monitor windows, and a component to monitor doors without near-by control pads.
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True
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False
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d. It would be better to have exactly 2 components because that's the number of cores in the CPU
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.True
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False
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