XMSS 2020 P1 Solution

1 2020 4E Prelim Exam Computing Paper 1 1 True, False, True, False [1] for each correct answer. Total 2 (a) - RGB colour codes, - Memory Dump, - IPv6 , - Media Access Control (MAC) address, - ASCII and Unicode, [1] for each correct answer. 2 (b) 1. It is to reduce the number of bytes required to represent the required information. 2. It is quick and easy to convert between hexadecimal and binary. Total 3 (a) (i) Solving the smaller parts is more manageable and easier to understand. The parts are evaluated separately and the solutions to these parts are then combined to solve the original problem. [1] for each underline key ideas (ii) Modularity is to identify tasks that are of different natures. Usually, these tasks can be separated from each other to become distinct (and sometimes unrelated) sub-problems. This usually results in sub-problems that are different from each other. [1] for each underline key ideas (b) Pattern recognition is identifying similarities or common elements among problems, solutions and steps in solutions. [1]Useful as similar problems would likely be solved by similar solutions, and similar solutions means you can reuse them. [1] for each underline key ideas Total 4 (a) Modulation – It is the process of converting digital data into a form suitable for transmission. [1] for each underline key ideas 4 (b) Router – Device that forwards packets between separate networks. [1] for each underline key ideas

2 4 (c) Data transfer is typically faster and more secure. (advantage) Faster : wired network typically has higher bandwidth than wireless network More secure : to snoop data, you need to have access to the physical hardware and wire while for wireless network, there is no need to have physical access. [1] for advantage and [1] for explanation 4 (b) Wireless network is low in cost and easy to configure and manage. (advantages) Low in cost : wireless network typically cost less as there is less cables to run Easy to configure and manage : easier for devices to join the network as there is no need to access a physical access point. No cables to manage and maintain. [1] for advantage and [1] for explanation Total 5 (a) Make regular backups Avoid opening emails/attachments/files from unknown sources Install and configure a firewall Install anti-virus anti-spyware software and perform regular scan Update software regularly Any 2. [1] for each. (b) Phishing – Use of emails and fake websites, that appear to be real, to trick people to enter their IDs and passwords and thus stealing them Pharming – Interception of requests sent from a computer to a real website, redirecting the request to a fake website for people to enter their IDs and passwords. [1] for each underline key ideas Total 6 (a) An interpreter is a code translator program that translates source code into machine code while the interpreted program is running [1] for each key point 6 (b) - Changes to the source code take effect immediately. - I