AP Computer Science Principles Big Idea 4: Computer Systems and Networks Practice Questio…
Practice questions for AP Computer Science Principles Big Idea 4 (Computer Systems and Networks), covering the internet, network protocols, and parallel computing, with explanations for every answer.
Questions
What is a computer network?
- A group of interconnected computing devices that can send and receive data
- A single computer with a large amount of memory
- A website that many people visit
- A program that runs on several operating systems
What is the Internet?
- A network of networks
- The collection of web pages people visit using a browser
- A single giant computer owned by one company that every device connects to
- A wireless signal sent from satellites
How is the World Wide Web related to the Internet?
- The Web is a system of linked pages that uses the Internet
- The Web and the Internet are two names for exactly the same thing
- The Internet runs on top of the Web
- The Web existed long before the Internet
The World Wide Web and the Internet are the same thing.
What is a protocol?
- An agreed-upon set of rules for how data is sent
- A physical cable that connects two routers
- A program that blocks viruses
- A list of websites a user has visited
Why are the Internet's protocols open rather than owned by one company?
- Open protocols let any device or network join and interoperate
- Open protocols are more secure because anyone can change them at any time
- Open protocols prevent new devices from connecting
- Open protocols make the Internet slower
What is the main job of the Internet Protocol (IP)?
- Addressing and routing packets
- Guaranteeing that every packet arrives in order
- Displaying web pages in a browser
- Translating domain names into numbers
What does TCP add on top of IP?
- Reliable, ordered delivery
- Faster delivery by skipping all of the error checks that IP performs
- Translation of domain names into IP addresses
- Encryption of every message
Which protocol is often used for live video calls and online games because it is fast and does not resend lost data?
- UDP
- TCP
- HTTP
- DNS
What is the main purpose of the Domain Name System (DNS)?
- To translate domain names into IP addresses
- To encrypt traffic between a browser and a website
- To route packets around broken connections
- To compress web pages
Which protocol does a web browser use to request web pages?
- HTTP
- UDP
- DNS
- IPv6
What is an IP address?
- A unique number that identifies a device on a network
- The name of a website, such as example.com
- The physical street address of an Internet provider
- A password used to access a network
About how many addresses can IPv4 provide with its 32-bit addresses?
- About 4.3 billion
- About 32
- About 4,300
- An unlimited number
Why was IPv6 developed?
- IPv4 was running out of addresses
- IPv4 could not send any data at all
- IPv6 removes the need for routers
- IPv6 is required to view web pages
IPv6 uses 128-bit addresses and IPv4 uses 32-bit addresses. How many times as many addresses does IPv6 allow?
- 2^96 times as many
- 4 times as many
- 96 times as many
- 128 times as many
What is bandwidth?
- The maximum amount of data that can be sent in a fixed amount of time
- The time it takes one bit to travel from sender to receiver
- The number of devices on a network
- The physical width of a network cable
What is latency?
- The delay between sending and receiving data
- The maximum amount of data that can be sent per second
- The number of routers on a path
- The size of a file being downloaded
In which unit is bandwidth typically measured?
- Bits per second
- Seconds
- Bytes stored
- Hertz per mile
A connection can have high bandwidth but also high latency.
DNS is the protocol that guarantees packets arrive in the correct order.
Devices made by different companies can communicate over the Internet because they follow the same protocols.
UDP checks that every packet arrives and resends any that are lost.
The Internet is designed to be scalable.
Which are Internet protocols?
- TCP
- IP
- HTTP
- UDP
- RAM
- CPU
Which statements about TCP are true?
- It requests retransmission of lost packets
- It puts packets back in the correct order
- It translates domain names into IP addresses
- It is used only for email
What system translates a domain name like example.com into an IP address?
What is the term for the maximum amount of data that can be sent over a connection in a fixed amount of time?
What does it mean that the Internet is scalable?
- It can grow to support more devices and users
- It can only support a fixed number of devices, set when it was first designed
- It shrinks when fewer people are online
- It works only in one country
On a video call, the picture is sharp, but there is a noticeable delay before the other person hears you. Which is the most likely cause?
- High latency
- Low latency combined with very high bandwidth
- Too many protocols
- An IPv6 address
A large file downloads slowly even though each piece arrives with little delay. What is most likely limited?
- Bandwidth
- Latency
- DNS
- The number of protocols in use
What is a computing device?
- A physical machine that can run a program
- A program that can run on a computer
- A protocol used on the Internet
- A list of IP addresses
What is a computing system?
- A group of devices and programs working together for a purpose
- A single transistor inside a processor
- One line of code
- An IP address
Which organization type develops and maintains many of the open standards used on the Internet?
- Standards bodies that publish open specifications
- Individual users
- A single private company that owns the Internet
- Website advertisers
Why does the Internet use a hierarchical system for IP addresses and domain names?
- It makes routing and lookup manageable at a huge scale
- It ensures only one country can control all of the addresses on the network
- It prevents devices from changing addresses
- It makes websites load in alphabetical order
Explain the difference between bandwidth and latency, using an example of each.
When data is sent over the Internet, how is it typically transmitted?
- In small chunks called packets
- As one continuous stream along a single reserved path
- As a single file that must travel all at once
- Through DNS servers only
What information does a packet carry besides the data itself?
- Metadata such as the source, destination, and sequence information
- A complete copy of the entire message
- The password of the receiving device
- The physical location of every router on the path
Packets from the same message arrive out of order. What happens?
- They are reassembled in the correct order
- The message is discarded and can never be sent again by the sender
- The receiver displays them in the order they arrived
- The sender is blocked
Packets belonging to the same message may take different paths to reach their destination.
All packets in a message must travel along the same path.
What is routing?
- Finding a path from sender to receiver
- Translating a domain name into an IP address using DNS
- Compressing data before it is sent
- Encrypting a message
What is a router?
- A device that forwards packets toward their destinations
- A program that translates domain names
- A cable connecting two computers
- A type of web browser
A router on a packet's usual path fails. What typically happens?
- The packet is sent along a different path
- Every packet on the Internet stops moving until that router is repaired
- The packet is permanently lost with no way to recover
- The sender's IP address changes
Why is routing on the Internet described as dynamic?
- Paths are chosen based on current conditions and can change
- Every route is fixed in advance and never changes
- Routes are chosen randomly
- Only one path exists between any two devices
What is a path in a network?
- A sequence of directly connected devices from a sender to a receiver
- A single cable between two devices
- The name of a website
- A list of passwords
Why is splitting a message into packets useful?
- Many messages can share the same connections at once
- It makes each message impossible for anyone else to read
- It removes the need for IP addresses
- It ensures packets arrive in order without TCP
What is the term for the small chunks that data is broken into for transmission over the Internet?
A packet's metadata includes information used to deliver it to the correct device.
A file is split into 500 packets. Packet 237 is lost. If the file is sent using TCP, what happens?
- Packet 237 is resent
- All 500 packets are resent from the beginning
- The file is saved with packet 237 missing
- The receiver guesses the missing data
A network has four computers connected as A–B, B–C, C–D. How many paths are there from A to D?
- 1
- 2
- 3
- 4