Digital Systems and Impacts
Core concepts
Digital systems questions span hardware, networks and the social consequences of technology. Candidates must understand the components of a computer system: CPU (control unit, arithmetic logic unit, registers), memory (RAM volatile, ROM non-volatile, cache), storage (magnetic, solid-state, optical), input and output devices, and the fetch-decode-execute cycle. Know the role of the operating system in managing memory, processes, files, devices and security.
Networking concepts include LAN versus WAN, topologies, bandwidth and latency, protocols (HTTP/HTTPS, TCP/IP, DNS), IP and MAC addressing, and the role of routers and switches. Security is heavily examined: authentication (passwords, multi-factor, biometrics), authorisation, encryption, firewalls, malware types, phishing and social engineering, plus backup strategies.
Impacts must be discussed in balance. Be able to argue both benefits and costs in areas such as automation and employment, privacy and surveillance, digital divide and equity of access, e-waste and energy use, and intellectual property. Traps: describing a technology without linking it to an effect; presenting one-sided arguments; confusing encryption with hashing; confusing a switch (within a LAN) with a router (between networks); assuming cloud storage removes security obligations.
Worked example
Question: "Discuss one social impact of cloud-based collaboration tools." A strong answer names the impact (improved remote collaboration), gives a mechanism (shared files and real-time editing), and balances it (dependence on connectivity disadvantages rural users). Rule of thumb: claim + mechanism + consequence + counterpoint.