IGCSE ICT Past Papers & Drilling (Paper 1): Hardware, Networks, Security

Question 1

Answer: D (Compiler (compiler)) System software runs the computer itself (compilers, device drivers, operating systems, utilities); spreadsheets, image editors and presentation tools are application software that solve a user’s task.

Question 2

Answer: C (Router (router)) A router forwards packets to other networks and is the internet exit point; a switch only forwards inside one LAN, a NIC is the interface in the computer, and a hub just repeats signals.

Question 3

Answer: D (Range check (range check)) A range check tests the data against the accepted limits as it is entered, so it is validation; double entry, visual checking and two operators comparing entries are all ways of verifying that input matches the source document.

Question 4

Answer: A (8) By definition 1 byte = 8 bits; 4, 16 and 32 are the sizes of other units (4 bits = 1 nibble) and not the definition of a byte.

Question 1

(a) Hardware is the physical parts of the computer; software is the programs that control the computer or process electronic data (4). (b) The CPU executes instructions and does the calculations; RAM temporarily holds the programs and data in use (2 + 2). (c) RAM is readable and writable and loses its contents when the power is off; ROM is normally read-only, written by the manufacturer and kept when the power is off (4).

Question 2

(a) A barcode scanner: it reads the printed code directly, fast and without keying each character (4). (b) A monitor or speaker: it confirms the record immediately so the student knows the loan went through (4). (c) Typing is slow and prone to wrong or missing characters, while a scanner reads the same printed code identically every time (4).

Question 3

(a) A LAN covers one building or campus and is managed by the school; a WAN covers a wide area and uses lines rented from a telecoms provider (4). (b) A router joins different networks and forwards packets towards their destination (for example the internet link); a switch forwards frames to the right computer inside one LAN using MAC addresses (4). (c) Encryption turns the data into cipher text, so without the key an interceptor cannot read it, protecting personal data and passwords (4).

Question 4

(a) A password and biometrics such as a fingerprint or face scan (2 + 2). (b) Two-factor authentication asks for two different kinds of evidence (something known, such as a password, plus something held, such as a code on a phone), so a stolen password alone is not enough to log in (4). (c) Install and update anti-malware software and do not open suspicious attachments or links (also acceptable: a firewall, downloading only from official sources, regular backups) (4).

Question 5

(a) A sensor outputs a continuously varying analogue signal, while a computer only processes digital data made of 0s and 1s, so an analogue-to-digital converter must be used first (4). (b) Validation: a range, format or presence check; verification: double entry or a visual check (4). (c) A check digit is calculated from the other digits by a set rule and stored at the end of the number; the system recalculates and compares it on entry, so a mismatch reveals a mistyped or transposed digit straight away (4).

Question 6

(a) The knowledge base, the inference engine and the user interface (4 marks for all three). (b) Robots work continuously with consistent quality and can do dangerous jobs such as those involving heat or toxic materials (4). (c) Automation removes some job roles, so without retraining, redeployment and honest communication staff morale and livelihoods suffer; it must be planned for (4).