Aqa A-Level Computer Science Study Guide Questions And Correct Answers

What is a host ID? {Ans: - Identifies specific device on a network - Right hand bits}What is symmetric encryption? {Ans: - Using same key to encrypt and decrypt - Key has to be transferred}What is a list? {Ans: - Collection of elements of a similar type ex. integers, characters, strings}What is buffer overflow? {Ans: - When a program accidentally writes data too small to handle - Can result in overflow data in a neighbouring space - Malware can deliberately do this and manipulate overflow into malicious instructions}Whats the MBR? {Ans: - Memory buffer register - Temporarily holds data moving between processor and main memory}What is a circular queue? {Ans: - Organised ring that reuses spaces that have been freed by dequeuing front of array}How can you represent many to many in a database? {Ans: - Linking table in middle is required}What is a man in the middle attack? {Ans: - Once an attacker has a key, they just wait for conversation - Sit in middle and pretend to be recipient/sender}Is a network ID static? {Ans: Yes}What is encryption? {Ans: - Ensuring data cannot be understood if you do not