AP Computer Science Essay Questions Assessment

AABB

A binary message consisting of four bits was sent to you by a friend. The message was supposed to be ABAB. Unfortunately, your friend set the bit on the wire once every 2 seconds, but you read the wire once every second. Assuming that the first bit was sent and read at the same time, what message did you receive instead?

Yes you can recover the original image if you figure out what the 1's and 0's represents for the white or black pixelated panels.

Assume your friend just sent you 32 bits of pixel data (just the 0s and 1s for black and white pixels). Could you recover the original image? If so, how? If not, why not?

No, you cannot determine where the message is going through depending on the traffic route it might take to get to its receiver.

Can you know in advance the path a message will take between you and another computer on the Internet? Justify your answer.

Yes, routing is more better than just average broadcasting because routing forwards and sends data across a network multiple of ways and a numerous amount of people can all connect to one router.

Describe the relative benefits of routing over a broadcast style of communication. Is routed traffic more secure than broadcasting? Justify your answer.

Place values in the binary systems is based on the number system of 2, which are 0 and 1. The place value goes up in a pattern of 1, 2, 4, 8, 16, 32, and so on. The place value of binary is times by 2 every time you go up by one digit.

In 100 words or less describe how place value is used in the binary number system. How is it similar or different from the way place value is used in the base 10 number system.

It is important to have rules in a numbering system because all the numbers can be in a orderly fashion in which to count off correctly. If we didn't have a proper number system we wouldn't be as advanced as we are in modern day society.

In 50 words or less, describe the concept of a number system. Why are rules required for a number system to be useful?

On popular social media websites, they display all information you post out to the public to view. This is an instance of why we should keep our personal information a secret to the world. You want to keep your information secretive from the public because stalkers and hackers on the internet can use your personal information to their advantage. I believe our privacy is tracked down by cookies and web beacons to locate what websites you are using frequently.

In what situations on the Internet do you typically want to keep information secret? From whom do you want to keep it to be secret? How do you think your privacy is maintained on the Internet now?

For an effective encryption scheme it should be convoluted and difficult to decipher, be able to last for a very long period of time, and you must be able to understand how to decipher back to its original text.

List 3 characteristics of the ideal encryption scheme.

"Do you like vanilla, strawberry, or chocolate ice cream?" is an example of a question that can't be answered in binary message because it has three different options to choose from and the message code can only pick between two possible values.

Provide an example of a question that could NOT be answered with a single binary message. Explain why this is the case, making reference to the definition of a binary message.

With all of Shakespeare's completed work would add up to 5 megabytes worth of data while a 4 minute MP3 song will be 4 megabytes. Shakespeare's work is approximately 1 megabyte bigger than the MP3 4 minute song.

Shakespeare's complete works have approximately 3.5 million characters. Which is bigger in file size: Shakespeare's complete works stored in plain ASCII text or a 4 minute song on mp3? How much bigger?

ASCII codes need to know that the codes do work. For the protocols that make up different functions of the internet with its set of rules, it assumes that most functions do exist.

The definition of HTTP makes use of the ASCII character set without reference to how these characters are encoded. Explain why this is an example of abstraction.

No the salesperson isn't telling the truth because with only 8GB of memory, a phones camera can only save up to 1,000; not 10,000 photos.

The salesperson in a cell phone store is telling me that the phone I'm considering has 8GB of memory, which means I can save 10,000 photos taken with the phone's camera! Is the salesperson telling me the truth? Why or why not?

decryption is a process of unscrambling the original message to make it readable while "cracking" a code is not having the encryption for deciphering the message, instead you go in and try many different combinations of code until you finally "crack" it.

What is the difference is between "cracking" a code and "decrypting" a message?

The IP address for a website can possibly change and it's used with that given URL.

Why do computers need to periodically check the DNS for websites you have already visited?

The reason for compressing anything digitally is because if any pattern is repetitive, we can simply that text down so it'll take up less space and it'll be less confusing.

Why do you want to compress anything? What's the point?

Whenever we look up a web site it goes to DNS servers when looking up the IP address of that website, it constantly does that every time you look up the page.

Why don't we need to know the IP addresses for our favorite sites?