Computer Science Principles Practice Test 245 Questions with Verified Answers,100% CORRECT

Computer Science Principles Practice Test 245 Questions with Verified Answers What is a ciphertext? - CORRECT ANSWER An unrecognizable secret formatted file. What does SSL stand for? - CORRECT ANSWER Secure Sockets Layer. What is a digital signature? - CORRECT ANSWER A signature that gives reason to believe that the sender was an authorized one. What is malicious software? - CORRECT ANSWER Another term for malware meaning harmful software. What does public key encryption not require? - CORRECT ANSWER A secure channel by which the initial key exchange must occur. Private Key Encryption - CORRECT ANSWER Another term for symmetric encryption. What is a firewall? - CORRECT ANSWER A security system that monitors incoming/outgoing network traffic. What is asymmetric encryption - CORRECT ANSWER Encryption that uses a public and private key. What is phishing? - CORRECT ANSWER An attempt to collect personal information and money by disguising as a trustworthy source. What is a DDOS attack? - CORRECT ANSWER A cyber attack where the perpetrator uses more than one IP address. What is social engineering? - CORRECT ANSWER The act of psychological manipulation of a human. What is ransomeware? - CORRECT ANSWER Software used to threaten a victim in order to pay. What is hash encryption? - CORRECT ANSWER Encryption done using a hash function. What is a digital certificate? What does it do? - CORRECT ANSWER An electronic document that proves ownership of a public key. What is another word for DNS spoofing? - CORRECT ANSWER DNS cache poisoning. What is a type of encryption that uses a hash function? - CORRECT ANSWER One-way encryption. What is pharming? - CORRECT ANSWER The act of redirecting website traffic to an alternative fake site What encryption type is commonly used for email? - CORRECT ANSWER Asymmetric encryption What is PGP? - CORRECT ANSWER Pretty Good Privacy What is net neutrality? - CORRECT ANSWER The law that asserts that all traffic on the internet is given equal priority. What does each computer connected to the internet have? - CORRECT ANSWER Its own unique address defined by the Internet Protocol. What is the problem with IP addresses? - CORRECT ANSWER IP addresses are difficult for us to remember. What is a DNS, and what does it do? - CORRECT ANSWER The Domain Name Server translates names to IP addresses. What is a good analogy for DNS? - CORRECT ANSWER It's like an address book mapping domain names to actual IP addresses. What are the steps of finding a server using DNS? - CORRECT ANSWER 1. Your computer will check its cache to see if it knows the address you are requesting. 2. The server will ask a root if it knows where the given top-level domain is (.com, .org, etc.). 3. Once we've found our top-level domain server we will ask that server if it can find the second-level domain server (). 4. We will then find the sub-domain by asking the second-level domain server () 5. The second-level domain server will then send our computer the IP address so we can save it! 6. Finally, our PC will send a get request to the IP address. What are the levels of domain and how are they read? - CORRECT ANSWER From highest to lowest level: root, top-level domain, second-level domain, and subdomain Why is DNS hierarchical? - CORRECT ANSWER Each layer is in charge of a small section of data, its easy to manage and add data, and it's much faster leading to a scalable, fault tolerant internet. How fast is the DNS process? - CORRECT ANSWER Extremely fast, completing tasks in milliseconds. What is the internet? - CORRECT ANSWER Physically: A massive network that connects individual networks using a series of complicated routers. Conceptually: A philosophy of making information and knowledge open and accessible to all. What is a network? - CORRECT ANSWER Two or more computer systems linked together. What do routers do? - CORRECT ANSWER Routers forward information around as requested by constituent computers. Who provides the routers we typically connect to? - CORRECT ANSWER The ISPs What is the core functionality of the internet? - CORRECT ANSWER To send information digitally from computer to computer. What three methods do we use to send bits? - CORRECT ANSWER Electricity (copper wires - ethernet), light (fiber optic cables), and radio waves. How is data transferred across the internet? - CORRECT ANSWER Data is transferred using packets that travel in the most efficient route across the internet. The internet was created with set protocols. (T/F) - CORRECT ANSWER True The internet was created with agreed upon protocols. (T/F) - CORRECT ANSWER True What is a widely agreed upon set of rules that standardize communication between nodes? - CORRECT ANSWER A protocol What is the term for using or donating your computer processing power for a larger group project called? - CORRECT ANSWER Distributed Computing The core functionality of the internet is to send information. (T/F) - CORRECT ANSWER True When sending bits across long distances, the best method would be - CORRECT ANSWER Fiber cable (light) A high frequency wave would be used to transmit a 1, where a low frequency wave would produce a -0-. (T/F) - CORRECT ANSWER True What is the capacity of data transfer in a system called? - CORRECT ANSWER Bandwidth What is the term for the time it takes for a bit to get from sender to receiver called? - CORRECT ANSWER Latency For the most efficient transfer rate, you'd want low latency. (T/F) - CORRECT ANSWER True What is bandwidth measured in and what does the measurement mean? - CORRECT ANSWER Bitrate. Higher bitrate means higher bandwidth. What is the bitrate of a system? - CORRECT ANSWER The amount of data (in bits) that can be sent in a fixed amount of time. How long have underwater cables connected the internet among countries for? - CORRECT ANSWER 157 years Data sent across the internet has a To address as well as a From address. (T/F) - CORRECT ANSWER True What does IP stand for? - CORRECT ANSWER Internet Protocol How many octets are in an IPv4 address? - CORRECT ANSWER 4 How many bits are in an IPv4 address? - CORRECT ANSWER 32 How many bits are there in one octet of an IPv4 address? - CORRECT ANSWER 8 How many possible IPv4 addresses are there? - CORRECT ANSWER Over 4 billion How many bits are there in an IPv6 address? - CORRECT ANSWER 128 How many 4 digit hexadecimal values constitute an IPv6 address? - CORRECT ANSWER Eight 4 digit hexadecimal values What does IETF stand for? - CORRECT ANSWER Internet Engineering Task Force What are the group members of the IETF? - CORRECT ANSWER Engineers, Designers, Vendors, and Researchers What is the Internet Protocol? - CORRECT ANSWER A protocol that defines the structure of an internet address and assigns a unique address to every device on the internet. Suppose we had an internet addressing protocol that used 4 bits to encode a single address. How many devices would be supported? How many unique addresses? - CORRECT ANSWER 16 DNS translates? - CORRECT ANSWER Names to IP addresses Where will your computer first look when you type a domain name? - CORRECT ANSWER Cache DNS works from right to left when translating a domain name. (T/F) - CORRECT ANSWER True What does TLD stand for? - CORRECT ANSWER Top level domain What are the pros and cons of using light (fiber cable) to transfer bits? - CORRECT ANSWER Pros: -Long distance -Fast (Speed of light) Cons: -Expensive What are the pros and cons of using an ethernet cable (copper) to transfer bits? - CORRECT ANSWER Pros: -Cheap Cons: -Only covers medium distances How is light bit transfer done? - CORRECT ANSWER Lights flash bright (1) and dim (0) What are the pros and cons of using radio waves to transfer bits? - CORRECT ANSWER Pros: -Wireless Cons: -Short distance How is radio transfer done? - CORRECT ANSWER Waves are transmitted in high frequency (1) or a low frequency (0) Why are clocks useful for transferring data? - CORRECT ANSWER Clocks tell the receiving computer that a new bit is being sent. What is the usual length of an ethernet connection? - CORRECT ANSWER Shorter than 1 kilometer What type of data transfer method has the lowest latency? - CORRECT ANSWER Fiber optic cables (5 Microseconds/kilometer) What is the internet data delivery system similar to? - CORRECT ANSWER Postal mail: -Physical street address (IP address) -Envelopes have To and From (Packets with To and From) What are the hierarchical parts to an IP address? (Largest to smallest) - CORRECT ANSWER Network (first octet; ex: a country), subnetwork (second octet; ex: a region), sub sub network (third octet; ex: the small network), device (last octet; ex: a computer) What has the internet enabled? - CORRECT ANSWER -Collaboration -Communication -Crowdsourcing -Anonymity -Censorship How many possible IP addresses are there for IPv6? - CORRECT ANSWER Over 340 Undecillion unique addresses (2^128) What is routing? - CORRECT ANSWER The process of sending data between two computers on the internet. How do routers determine where to send bits? - CORRECT ANSWER They determine the lowest cost based on the proximity to the IP address, the trustworthiness of the router, and the speed of the connection. Why is router redundancy good? - CORRECT ANSWER Improves reliability, creates a fault tolerant system, and makes the internet have better performance which allow the internet to scale. How many hexadecimal digits does an IPv6 have? - CORRECT ANSWER 32 What are packets? - CORRECT ANSWER The tiny units of data sent over a network. What metadata are packets typically labeled with? - CORRECT ANSWER The To and From address along with the size of the packet. How is the layout of a packet defined? - CORRECT ANSWER Internet Protocol defines the layout of a packet by saying: 1. A destination IP address 2. A from IP address 3. The actual data being sent How do we send multiple packets? - CORRECT ANSWER Transmission Control Protocol (TCP) What does Transmission Control Protocol (TCP) do? - CORRECT ANSWER TCP checks that all the packets arrived and ensures that they can be put together in proper order. What additional metadata do TCP packets have? - CORRECT ANSWER Packet number Packets sent using TCP need to arrive in order (T/F) - CORRECT ANSWER False How is data structured inside a packet? - CORRECT ANSWER HTTP standardizes the language used for communication between servers. What does HTTP stand for? - CORRECT ANSWER HyperText Transfer Protocol (HTTP) What does HTML stand for? - CORRECT ANSWER HyperText Markup Language (HTML) TCP/IP, DNS, and Routing all work together to send packets over the internet (T/F) - CORRECT ANSWER True What does URL stand for? - CORRECT ANSWER Uniform Resource Locator What are the where and what of the URL? - CORRECT ANSWER The where is the Domain () and the when is the path (/) What does HTTP do? - CORRECT ANSWER It ensures that the information inside the packets can be understood. What do packets contain? - CORRECT ANSWER The data being transmitted and the metadata of the packet What is a term for control information that helps route data through the internet? - CORRECT ANSWER Metadata Routing on the Internet is fault tolerant, but not always redundant. (T/F) - CORRECT ANSWER False Redundancy in the Internet improves reliability. (T/F) - CORRECT ANSWER True Which of the following would be a sub-domain of ? A) B) C) D) - CORRECT ANSWER C) A Is redundancy on the internet good? Why? - CORRECT ANSWER Redundancy has good qualities; if several routers fail, data can still be transferred and many devices can be added to the network without affecting traffic. To get the fastest speeds, we would want our latency and bandwidth to do what? - CORRECT ANSWER Latency should decrease (1 ms-- 0.75 ms) while bandwidth should increase (1 mb/s -- 2 mb/s) Most routing on the Internet is hierarchical. (T/F) - CORRECT ANSWER True Most data can follow more than one path to the destination device. (T/F) - CORRECT ANSWER True The structure of the internet makes it difficult to grow significantly. (T/F) - CORRECT ANSWER False Domain names and IP addresses are assigned randomly. (T/F) - CORRECT ANSWER False What is bandwidth? - CORRECT ANSWER The rate at which data is transferred in a set amount of time. Packets sent from a computer always arrive at the destination in order so that they can be reassembled. (T/F) - CORRECT ANSWER False Which protocol is used to establish a secure connection between browsers and servers to ensure that no data is lost? - CORRECT ANSWER Secure Sockets Layer/ Transport Layer Security (SSL/TLS) Why can many different companies create devices that work on the same network? - CORRECT ANSWER Open standards and protocols Which of the following is an example of a subdomain of according to DNS? A) B) C) D) - CORRECT ANSWER D) The internet is the same thing as the World Wide Web. (T/F) - CORRECT ANSWER False HTTP is a protocol primarily used for electronic mail. (T/F) - CORRECT ANSWER False When a request is made by a client computer, HTTP ensures that the client is connected to the requested web page for the entire duration it's being viewed. (T/F) - CORRECT ANSWER False What are the benefits of open standards like HTTP? - CORRECT ANSWER They allow devices and applications across many networks to work together and communicate and are always being created and revised by Internet users around the world. A benefit of the open standards of the internet is that individuals can make changes to the standards for their own personal use. (T/F) - CORRECT ANSWER False What is the primary reason that routing on the internet is redundant? - CORRECT ANSWER Networks are still available in case of a path or router failure. TCP/IP is exactly two sets of protocols (TCP and IP). (T/F) - CORRECT ANSWER False TCP is a set of standards for how computers communicate with each other. (T/F) - CORRECT ANSWER True IP is a set of standards for routing and transferring information on a network. (T/F) - CORRECT ANSWER True TCP/IP is the most widely used standard for packets and routing. (T/F) - CORRECT ANSWER True If Jeff measures the amount of time it takes for a packet to get from Google to his' computer, what is he measuring? - CORRECT ANSWER Latency Packets don't contain any information about the destination IP address. (T/F) - CORRECT ANSWER False Packet switching results in a decentralized network. (T/F) - CORRECT ANSWER True It is possible that each packet might take a completely different path to the end host. (T/F) - CORRECT ANSWER True Each packet of information is sent independently. (T/F) - CORRECT ANSWER True What are the benefits of the hierarchical approach to setting up a network? - CORRECT ANSWER It decreases congestion in the network and makes data transferring much more efficient. What is the basic idea of fault tolerance? - CORRECT ANSWER If part of a system fails, the operation continues without interruption. What is the first layer of the Open Systems Interconnection (OSI) model? - CORRECT ANSWER The physical layer The hierarchy of domain name labels descends from left to right. (T/F) - CORRECT ANSWER False Every domain name ends with a top level domain label. (T/F) - CORRECT ANSWER True The left most label of the domain name identifies the server. (T/F) - CORRECT ANSWER True There is virtually no limit on the number of subdomains in a domain name. (T/F) - CORRECT ANSWER True Which of the following domain names are part of the same top tier? A) geA.edu B) geA.net C) geB.edu D) geB.com - CORRECT ANSWER A)geA.edu and C)geB.edu What enables individuals to be on the internet while others are connected to the same source without affecting performance? - CORRECT ANSWER Redundant Routers Top-level domains in the DNS hierarchy can be organizational or geographical. (T/F) - CORRECT ANSWER True What enables users to access sites at the same speed despite many new websites being added every day? - CORRECT ANSWER Hierarchical DNS There are no rules or guidelines for creating a new IP address. (T/F) - CORRECT ANSWER False Each of the octets in an IP address can be any number between 0 and 255. (T/F) - CORRECT ANSWER True What do HTTPS and SSL ensure? - CORRECT ANSWER That the identity of the server involved in an interaction can be trusted and that any messages being sent are encrypted and thus secure. HTTPS and SSL ensure that credit cards, passwords, and any other private information will not be remembered by the website. (T/F) - CORRECT ANSWER False Host names can be found in a database that can be distributed over many servers. (T/F) - CORRECT ANSWER True Why was IPv6 introduced as the new version of the Internet Protocol? - CORRECT ANSWER IPv4 could not support the large number of devices connecting to the internet. The new IPv6 features advanced techniques to redirect network traffic, making the Internet faster and easier to use. (T/F) - CORRECT ANSWER False The new IPv6 categorizes IP addresses, which makes them easier to remember and locate. (T/F) - CORRECT ANSWER False HTTP is the protocol for communicating with web servers and transferring web pages and other data back to a browser. (T/F) - CORRECT ANSWER True HTTP is a protocol used to create and implement web pages. (T/F) - CORRECT ANSWER False What are two ways that the internet has changed collaboration? - CORRECT ANSWER Cloud computing and video conferencing Which of the following identifies a device using the Internet? A) An SMTP B) A domain name C) An IP address D) A packet - CORRECT ANSWER C) An IP address How are protocols such as HTTP, SMTP, and IP created? - CORRECT ANSWER A worldwide group of volunteers draft, revise, and publish protocols. (IETF) Individuals make their own protocols that occasionally catch on and are used by most of the Internet. (T/F) - CORRECT ANSWER False Domain names are easier for humans to remember than the IP addresses of frequently visited websites. (T/F) - CORRECT ANSWER True Domain names must be applicable to their site content. (T/F) - CORRECT ANSWER False Internet standards cannot be altered or removed once they are created. (T/F) - CORRECT ANSWER False Internet standards ensure that hardware and software created by different companies will be able to communicate with each other online. (T/F) - CORRECT ANSWER True Internet standards are specific procedures and rules that are created in order to benefit the Internet community. (T/F) - CORRECT ANSWER True Although the standards that govern the Internet (like IP and DNS) might change, they will not be affected by a small group or party. (T/F) - CORRECT ANSWER True It is incredibly difficult to change the common protocols and standards of the Internet once they have been created. (T/F) - CORRECT ANSWER False It is hard to persuade people to join the IETF since decisions rarely affect the way the Internet is currently used. (T/F) - CORRECT ANSWER False What is a protocol? - CORRECT ANSWER A widely agreed upon set of standards for communication across nodes. What does SMS stand for? - CORRECT ANSWER Short messaging service 500 % 100? - CORRECT ANSWER 0 What is 8 (decimal) in binary? - CORRECT ANSWER 1000 What is 11 (decimal) in hex? - CORRECT ANSWER b What does MITM stand for? - CORRECT ANSWER Man in the Middle What does CA stand for? - CORRECT ANSWER Certificate Authority What is the word that means to divide and take the remainder? - CORRECT ANSWER Modulus (%) What is 8 (in decimal) in hex? - CORRECT ANSWER 8 What is 15 (decimal) in hex? - CORRECT ANSWER f What is programming that can be understood mostly by humans? - CORRECT ANSWER High-level programming What is an example of high level programming? - CORRECT ANSWER Java, Python, C++, Pascal, etc. What is programming that can be understood by machines? - CORRECT ANSWER Low-level programming Who are the founders of the internet? - CORRECT ANSWER Bob Khan and Vint Cerf What is an example of low-level programming? - CORRECT ANSWER Binary What exists at every place between two devices across the internet? - CORRECT ANSWER A router What type of analysis aims to determine emotions? - CORRECT ANSWER Sentimental analysis What are the big four V's? - CORRECT ANSWER Veracity, Volume, Variety, and Velocity Which of the big four V's would best describe real-time and near-time? - CORRECT ANSWER Velocity It's important to declare the type of variable in Java. (T/F) - CORRECT ANSWER True "int" is only used when declaring a variable - CORRECT ANSWER False "char" type represents a single character. (T/F) - CORRECT ANSWER True Strings are a primitive type. (T/F) - CORRECT ANSWER False Strings must start with a capital "S" (T/F) - CORRECT ANSWER True When naming a variable, it must begin with a letter , $, or _. (T/F) - CORRECT ANSWER True Variable names are case sensitive. (T/F) - CORRECT ANSWER True Combining strings with other strings or combining strings with other variables is an example of what? - CORRECT ANSWER Concatenating What is the shortcut for counter = counter + 1;? - CORRECT ANSWER counter++; What is the shortcut for x = x - y in Java? - CORRECT ANSWER x-= y; What does it mean to truncate? - CORRECT ANSWER To remove the decimal component. 150 % 100? - CORRECT ANSWER 50 When you send information by typing a form over the internet, you are sending a "post" request? (T/F) - CORRECT ANSWER True HTTP and DNS manage the sending and receiving of web files. (T/F) - CORRECT ANSWER True Using IPv6 network addressing, it is estimated that would be the equivalent of having an IP address for every grain of sand in the world. (T/F) - CORRECT ANSWER True IP packets flow across the internet together until they reach their destination. (T/F) - CORRECT ANSWER False What does "cheapest" path mean when referring to packets? (one word answers) - CORRECT ANSWER Time, Politics, or Relationship The best route for packets to travel is the most direct one. (T/F) - CORRECT ANSWER False Sending multiple bits through fiber cable is dependent on what? - CORRECT ANSWER The bounce angle of light. What two ways can a virus infect your computer? - CORRECT ANSWER Fake Install & Security Backdoor What is the term for when hackers overwhelm a site with too many requests? - CORRECT ANSWER Distributed Denial of Service What is the biggest reason for systems being hacked? - CORRECT ANSWER Human error What is the term for scrambling or changing a message to hide it? - CORRECT ANSWER Encryption When the sender and receiver use the same key to encrypt/decrypt a message, it is called what? - CORRECT ANSWER Symmetric encryption or private key encryption What is the term for something that can represent different values in an expression? - CORRECT ANSWER Variable What is iteration? - CORRECT ANSWER When a process is executed again and again The fact that open standards are developed by panels of experts makes them very trustworthy. (T/F) - CORRECT ANSWER True What does a CA do? - CORRECT ANSWER CA's issue digital certificates that certify ownership of public keys. Which encryption method is most widely used? Why? - CORRECT ANSWER Public key encryption; this method doesn't require a secure channel What type of encryption works well but requires both parties to have the same key? - CORRECT ANSWER Symmetric or private key encryption The trust model of the internet makes the internet relatively inexpensive. (T/F) - CORRECT ANSWER True Many hardware, software, and human components contribute to the security of the internet. (T/F) - CORRECT ANSWER True What is the benefit of choosing good variable names? - CORRECT ANSWER It makes the program easier to edit and debug What is a benefit of the trust system of the internet? - CORRECT ANSWER It enables cooperation between two online nodes. The trust model of the internet ensures absolute security. (T/F) - CORRECT ANSWER False The internet is designed to scale so that more systems and networks can join at any time. (T/F) - CORRECT ANSWER True Many methods of cybersecurity rely on cryptography. (T/F) - CORRECT ANSWER True There are hardware and software components of cybersecurity in addition to human components. (T/F) - CORRECT ANSWER True The trust model of the internet refers to computers trusting entities that have been trusted by others. (T/F) - CORRECT ANSWER True Public key encryption and symmetric encryption are two very common cybersecurity techniques that rely on cryptography. (T/F) - CORRECT ANSWER True What would have to be done to violate the security of a message encrypted with a public key? - CORRECT ANSWER Another party gaining access to the private key What is the act of reporting an incorrect IP address and effectively rerouting the original query to a different website? - CORRECT ANSWER DNS spoofing. The right most label of the domain name identifies the server. (T/F) - CORRECT ANSWER True Redundancy creates unnecessary routers in the network. (T/F) - CORRECT ANSWER False (key word: unnecessary) Each network connected to the internet is owned by a separate entity - a government, business, organization, or individual. (T/F) - CORRECT ANSWER True How do programmers determine if an algorithm takes a reasonable amount of time? - CORRECT ANSWER Programmers count the number of steps Algorithms need to run in a reasonable amount of time in order to be considered practically useful. (T/F) - CORRECT ANSWER True A hash calculation appears within a Digital Certificate and is created from a CA. (T/F) - CORRECT ANSWER False What is it called when a maximum value is exceeded in a program? - CORRECT ANSWER An overflow error What is a set of instructions in order called? - CORRECT ANSWER A sequence Why do we use if statements in Java? - CORRECT ANSWER To do something only if a condition is true What is something that can be a part of an array? - CORRECT ANSWER Parameters What is it called when a process reduces the duplication of code? - CORRECT ANSWER An abstraction What do we use control structures for in JavaScript? - CORRECT ANSWER To control the flow of the program What is a programming language that is object-oriented, and specifically designed to have as few implementation dependencies as possible? - CORRECT ANSWER Java What is something that can be used in a program to pass information between functions? - CORRECT ANSWER A variable What is a code comment? - CORRECT ANSWER A way to give your reader notes to explain what your code doing What is 11010 in decimal? - CORRECT ANSWER 26 What is the purpose of using a for loop in code? - CORRECT ANSWER To repeat something a fixed number of times What is the part of a computer instruction that specifies data that is to be operating on or manipulated and, by extension, the data itself? - CORRECT ANSWER An operand What is code that is repeated? - CORRECT ANSWER Iteration What is a street in a Karel world? - CORRECT ANSWER Row 11011 converted to decimal - CORRECT ANSWER 27 11110 converted to decimal - CORRECT ANSWER 30 What is a parameter? - CORRECT ANSWER An input in a function What is the result of this expression? 5 + 2 / 3 + 1 - CORRECT ANSWER 6 When code is executed again and again - CORRECT ANSWER Loop What is the output of the following lines? int x = 24; Sln("The total is " + x + x); - CORRECT ANSWER The total is 2424