2023 Edexcel IGCSE Information and Communication (ICT) 模擬試題連答案詳解

A wireless range extender (or repeater) picks up an existing Wi-Fi signal from a wireless router and rebroadcasts it, thereby extending the range of the home network into areas with weak reception. A Network Interface Card (NIC) enables a single device to connect to a network. A network switch is used to connect multiple devices within a wired local area network. A dial-up modem is an older technology used to connect to the internet over analogue telephone lines.

1 mark for the correct answer (b).
- Award 0 marks for any other option.

WPA3 (Wi-Fi Protected Access 3) is the newest and most secure wireless security protocol, providing strong data encryption and protection against brute-force attacks. MAC address filtering and hiding the SSID do not encrypt wireless data and can be easily bypassed by motivated attackers. Disabling DHCP only stops automatic IP allocation, which is not an encryption mechanism.

1 mark for the correct answer (b).
- Award 0 marks for any other option.

A Virtual Private Network (VPN) establishes a secure, encrypted 'tunnel' over the public internet, allowing the remote worker's device to securely access resources on the private office LAN. FTP (File Transfer Protocol) is used only for transferring files and does not provide a secure gateway to an entire network. LAN and PAN are network classifications rather than secure remote-access technologies.

1 mark for the correct answer (a).
- Award 0 marks for any other option.

A switch is a networking device that connects devices on a Local Area Network (LAN). It uses MAC addresses to identify destination devices and forwards data packets specifically to them, improving network efficiency and security compared to a hub.

Award 1.67 marks for stating 'Switch' or 'Network switch'. Do not accept 'Hub' or 'Router'.

WPA3 (Wi-Fi Protected Access 3) is the standard cryptographic protocol used to encrypt data sent over wireless networks, protecting it from interception and unauthorized access.

Award 1.67 marks for stating 'WPA3' or 'WPA2' or 'Wi-Fi Protected Access'. Do not accept 'WEP' as it is obsolete and insecure.

A Virtual Private Network (VPN) creates a secure, encrypted tunnel over a public network such as the internet. This allows remote workers to safely transmit and receive confidential corporate data as if their device were directly connected to the private network.

Award 1.67 marks for 'VPN' or 'Virtual Private Network'. Do not accept 'Firewall' or 'HTTPS'.

1 mark for identifying a valid advantage (e.g., lower cost, simple setup, no central server requirement). 1.5 marks for explaining this in the context of a home network (e.g., individual devices can share resources directly without needing complex administration or expensive dedicated server hardware).

Award up to 2.5 marks: - 1 mark: Valid advantage identified (e.g., lower setup cost, no need for specialist administration, no single point of network failure). - 1.5 marks: Clear development of how this advantage applies or benefits a home user/network (e.g., saving money on server licences, or avoiding complete network failure if one home computer breaks).

1 mark for stating that it connects different networks (the local home network to the internet). 1.5 marks for explaining the mechanism of routing data packets using IP addresses to ensure they reach the correct destination.

Award up to 2.5 marks: - 1 mark: Stating connection of local network to the internet / external network. - 1.5 marks: Explaining packet forwarding, address translation, or routing of data to appropriate IP destinations.

1 mark for stating that WPA encrypts/scrambles the wireless data transmission. 1.5 marks for explaining that interception is made useless because the data cannot be read or understood without the decryption key/passphrase.

Award up to 2.5 marks: - 1 mark: Mention of encryption / scrambling of data during transmission. - 1.5 marks: Explanation of the impact (unauthorized eavesdroppers cannot read or reconstruct the data without the key).

1 mark for mentioning the creation of a secure, encrypted tunnel over the public internet. 1.5 marks for explaining that this prevents interception and protects corporate data confidentiality when using a home ISP.

Award up to 2.5 marks: - 1 mark: Identification of encrypted tunnel / secure link over public network. - 1.5 marks: Explanation of protecting business data from interception/unauthorized access on home/public connections.

An embedded system is a dedicated computer system built inside a larger mechanical or electrical system to perform a specific, pre-defined function (e.g., the control system in a washing machine or microwave). Unlike general-purpose computers, they are highly specialized.

1 mark for the correct option (C). No marks for incorrect options.

Clock speed is measured in Hertz (Hz) and represents the number of cycles a CPU can execute per second. 3.2 GHz (Gigahertz) means the processor's internal clock ticks 3.2 billion times per second, allowing it to perform up to 3.2 billion fetch-decode-execute cycles per second.

1 mark for identifying the correct definition of clock speed in GHz (B).

Solid State Drives (SSDs) use flash memory chips and contain no moving mechanical parts. This makes them highly durable (resistant to drops and shocks), silent, and much more energy-efficient, which is critical for preserving battery life in portable devices.

1 mark for selecting C. All other options are incorrect facts about SSD performance/cost.

RAM is volatile read/write memory used to temporarily store data and instructions currently in use by the CPU. ROM is non-volatile read-only memory used to store permanent, essential startup instructions (such as the BIOS/bootstrap loader).

1 mark for the correct statement distinguishing RAM and ROM (C).

Defragmentation utility software reorganizes fragmented files on a magnetic disk so that the data blocks for each file are stored in contiguous (adjacent) sectors. This minimizes the movement of the physical read/write head, resulting in faster file access and retrieval times.

1 mark for correctly explaining how defragmentation improves physical disk performance (C).

In control systems, the microprocessor continuously receives sensor readings, compares these input values with pre-programmed threshold parameters (such as target temperatures), and decides whether to send electrical signals to control output devices (actuators) such as window motors or heaters.

1 mark for identifying the control loop role of comparing inputs to pre-sets (B).

An embedded system is designed with a specific dedicated function within a larger electrical or mechanical system. Unlike general-purpose computers like PCs, embedded systems have highly optimized hardware and software that cannot easily be altered by the user, and they often lack a full operating system or complex user interface.

Award 1 mark for each correct feature up to a maximum of 2 marks: - Designed for one specific task (1 mark) - Built into a larger device or system (1 mark) - Uses a micro-controller or microprocessor with limited, dedicated software (1 mark) - Has little or no user interface (1 mark) - Low power consumption or low hardware resources needed (1 mark).

Cache memory is extremely fast, small SRAM located directly on the CPU chip. By copying the most frequently needed instructions and data into cache, the CPU avoids having to access the slower system RAM. This speeds up the fetch-decode-execute cycle and improves the CPU's overall data processing rate.

Award 1 mark for identifying the purpose/speed of cache and 1 mark for explaining the impact on CPU performance: - Cache is high-speed memory that stores frequently/recently accessed data/instructions (1 mark). - This reduces the time the CPU spends waiting for data from main memory/RAM, which speeds up the fetch-decode-execute cycle (1 mark).

Rugged laptop use in field environments involves physical shocks, drops, and bumps. A magnetic HDD contains spinning platters and read/write heads that can crash and corrupt data under movement. An SSD uses solid-state flash memory with no mechanical parts, ensuring durability. Additionally, lower power consumption means the laptop battery lasts longer in remote areas, and the lighter weight increases portability.

Award 1 mark for each explanation linking a physical feature to the field scenario, up to 3 marks: - SSDs have no moving parts, so they are shock-proof and will not fail if the laptop is dropped or vibrated (1 mark). - SSDs consume less power, which extends battery life when working away from mains electricity (1 mark). - SSDs are lighter in weight, which makes the laptop easier to carry in the field (1 mark). - SSDs have faster data access speeds, allowing quicker startup and saving of research data (1 mark).

The main distinction is volatility: RAM is volatile temporary memory that is wiped clean when power is lost. ROM is non-volatile permanent memory that keeps its instructions, such as the BIOS bootup sequence, even when the system is switched off.

Award 1 mark for a complete contrast of volatility: - RAM is volatile and ROM is non-volatile (1 mark) OR - RAM loses its contents when power is off whereas ROM retains its contents (1 mark). Reject answers that only describe one without contrasting.

When files are saved, modified, and deleted, they become fragmented and scattered across different sectors of a magnetic disk. A defragmenter reorganises the blocks of data so that each file is stored in contiguous, sequential sectors. This means the mechanical drive head does not need to move back and forth across the platters as much, leading to faster file load times and smoother system operation.

Award up to 2 marks for a logical explanation: - Reorganises fragmented files so that their parts are stored together in contiguous/sequential sectors (1 mark). - Reduces physical movement of the drive's read/write head / allows files to be read in a single continuous sweep (1 mark). - Results in faster data retrieval/loading speeds (1 mark).

Defragmentation software scans the magnetic hard disk and rearranges scattered data blocks of files so that they are stored in consecutive (contiguous) sectors. It also consolidates free space. As a result, the drive's read/write head does not need to move back and forth across different parts of the disk platter to read a single file. This reduction in physical movement significantly decreases read/write times and improves system speed.

Award 1 mark for describing how the software reorganises files into contiguous/consecutive blocks or consolidates free space. Award 1 mark for explaining the impact, such as reducing the physical movement of the read/write head or decreasing file retrieval/access times.

In an embedded system like a washing machine, the microprocessor acts as the brain. It continuously reads input data from sensors (e.g., temperature and water level sensors) and processes this data based on the selected program's instructions. It then sends control signals to output devices or actuators (e.g., the heating element, water valve, or motor) to control the washing process.

Award 1 mark for stating that the microprocessor receives and processes inputs/data from sensors or user selections. Award 1 mark for explaining that it sends output/control signals to actuators or components (such as heaters or motors) to perform physical actions.

A Virtual Private Network (VPN) creates an encrypted tunnel over the internet, securing data transmitted between the remote laptop and the office network.

1 mark for option B. 0 marks for any other option.

With hosted software, data is stored on the provider's cloud servers and backed up automatically by the host, reducing the IT maintenance burden on the business.

1 mark for option B. 0 marks for any other option.

A VPN provides a secure tunnel over the internet. It encrypts all data transmitted, protecting sensitive company data from being intercepted. It also assigns the remote device an IP address from the company network, granting access to private internal systems and files that are not publicly accessible.

Award 1 mark for each valid reason up to a maximum of 2 marks:
- Encrypts data in transit / secures data from interception (1)
- Allows access to restricted/private internal network resources (1)
- Masks the user's local IP address/location (1)
- Authenticates the user's identity securely (1)

Hosted software is stored and run on external servers. This provides flexibility as users only need a browser and internet connection to work. Additionally, maintenance tasks like software updates and patches are handled server-side by the service provider, reducing the administrative burden and local storage requirements for the user.

Award 1 mark for each valid advantage up to a maximum of 2 marks:
- Accessible from any location / any device with internet connectivity (1)
- No/less local storage space required on the device (1)
- Automatic updates / maintenance managed by the provider (1)
- Easier collaboration / real-time sharing with other users (1)
- Lower processing power required on the local machine (1)
Do not accept: 'It is free' or 'It is cheaper' without qualification.

Web browsers display specific visual cues in the address bar to show that a site uses SSL/TLS encryption. The 'https' protocol indicates a secure connection, and the padlock icon represents a verified security certificate.

Award 1 mark for each valid indicator up to a maximum of 2 marks:
- The protocol 'https' is visible in the URL (1)
- A padlock icon is shown in the address bar (1)
- The address bar background or padlock changes color (e.g. green) to show validation (1)
Do not accept: references to features not in the address bar itself (e.g. security logos on the page, privacy policy link).

Using a pseudonym or screen name and an avatar instead of real names and real photographs prevents other users in the online community from linking the profile to the individual's true identity, thereby protecting them from potential stalking, doxxing, or identity theft.

Award 1 mark for identifying a valid method (e.g., using a pseudonym/avatar, adjusting privacy settings) and 1 mark for a linked explanation of how this protects their personal identity (e.g., prevents linking to real-world identity, restricts access to personal information).

A VPN establishes an encrypted tunnel between the user's device and the VPN server. This ensures that even if data packets are intercepted by bad actors on the unsecured public Wi-Fi network, the content remains unreadable, protecting sensitive credentials and personal data.

Award 1 mark for identifying a benefit/feature (e.g., data encryption / tunneling) and 1 mark for explaining how this helps on a public Wi-Fi hotspot (e.g., prevents data interception / reading of sensitive data by hackers).

Email providers often have strict limits on attachment sizes, which restricts sending high-resolution photos. An online photo-sharing platform allows users to upload high-quality images once and share them via a single URL, saving bandwidth for both sender and recipient.

Award 1 mark for identifying a benefit (e.g., bypasses file size limits, saves local storage/bandwidth, allows centralized collaboration) and 1 mark for explaining how this is an improvement over emailing (e.g., avoiding bounce-backs from large files, allowing instant viewing of multiple albums via a single link).

Hosted application software runs on remote servers and is accessed via a web browser. If the user's internet connection is lost or unstable, they will not be able to access the software or edit their files, unlike locally installed applications which run directly from the computer's hard drive.

Award 1 mark for identifying a disadvantage of hosted software (e.g., dependency on internet connection, ongoing subscription costs, potential data privacy concerns) and 1 mark for explaining why this is a disadvantage compared to local installations (e.g., cannot work offline, loss of productivity during outages).

Wireless networks rely on radio frequency (RF) signals to transmit data. Solid, dense materials like concrete absorb the energy of these waves and reflect them, weakening the signal strength (attenuation) by the time it reaches the receiver, leading to slower speeds or complete loss of connection.

Award 1 mark for identifying the physical process (e.g., absorption, reflection, or attenuation of radio signals) and 1 mark for explaining the impact on the wireless network (e.g., reduced signal range, lower data speeds, or dropped connections).

When using a third-party payment gateway, the customer's financial details (like credit card numbers or bank accounts) are securely stored with the payment processor. The retailer only receives the payment authorization and confirmation, minimizing the risk of the customer's financial data being stolen if the retailer's database is breached.

Award 1 mark for identifying a security feature of third-party payment processors (e.g., masking financial details, centralized encryption) and 1 mark for explaining how this protects the buyer (e.g., prevents the retailer from seeing/storing the card number, reduces exposure to merchant database hacks).

Providing downloadable, low-resolution video files and text-based transcripts allows students with slow or metered internet connections to access learning materials. Low-resolution files use less data, and downloadable content can be retrieved during off-peak hours or when a connection is temporarily available, minimizing the barrier of low bandwidth.

1 mark for identifying the correct method: B. Under the digital divide, students with low bandwidth cannot access HD live streams (A) or high-bandwidth VR environments (D), and high-performance graphics cards (C) do not solve network bandwidth limitations and add financial barriers.

To participate in an interactive video conference, a student needs to send their audio or video (input) and receive the host's audio or video (output). A microphone or webcam serves as a valid input device, while speakers, headphones, or a monitor serve as valid output devices.

Award 0.75 marks for a correct input device (e.g., microphone, webcam). Award 0.75 marks for a correct output device (e.g., speakers, headphones, monitor). Do not accept generic terms like computer.

Transitioning to online learning reduces physical resource consumption such as paper and transport fuel, leading to lower carbon emissions. However, it increases electricity usage to power digital devices and data centers, and contributes to electronic waste.

Award 0.75 marks for a valid positive impact (e.g., reduced paper use, reduced vehicle emissions). Award 0.75 marks for a valid negative impact (e.g., increased e-waste, increased power consumption by servers).

1 mark for identifying an advantage (e.g., reduced background noise or prevention of echo). 1 mark for explaining the reason/how it works (e.g., the speaker is isolated from the microphone, or the microphone is closer to the mouth).

Award 1 mark for a valid advantage and 1 mark for an explanation of how it improves the audio quality. Max 2 marks.

1 mark for identifying a benefit (e.g., flexibility of study time, self-paced learning). 1 mark for explaining how this benefits the student's learning process (e.g., ability to replay difficult sections to improve understanding).

Award 1 mark for identifying the benefit and 1 mark for explaining the positive impact on student learning. Max 2 marks.

1 mark for stating that it filters out irrelevant pages/narrows the search results. 1 mark for explaining how this saves time or improves search efficiency.

Award 1 mark for stating how boolean operators modify the search results and 1 mark for explaining the improvement in efficiency. Max 2 marks.

1 mark for identifying a negative environmental impact (e.g., high electricity consumption of servers, electronic waste from upgrading devices). 1 mark for explaining the environmental consequence (e.g., increased carbon footprint, toxic chemicals in landfill).

Award 1 mark for identifying a negative environmental impact and 1 mark for explaining its consequence. Max 2 marks.

An effective response should discuss the following key areas:

1. **Factors contributing to the Digital Divide:**
- **Geographical:** Rural areas often lack high-speed broadband infrastructure compared to urban centers, limiting access to stable internet connections.
- **Economic:** Low-income households cannot afford modern digital devices (laptops, tablets) or the ongoing cost of high-speed internet/mobile data.
- **Physical/Social:** Students with disabilities may lack specialized assistive technologies (screen readers, adaptive hardware). Additionally, a lack of digital literacy among parents/guardians can hinder a student's ability to navigate online learning platforms.

2. **Impact on Online Learning:**
- Students without reliable internet cannot attend synchronous (live) video lessons, leading to learning gaps.
- Lack of dedicated devices means siblings may have to share a single device, restricting their study time.
- Students are unable to access heavy multimedia learning resources, download textbooks, or submit assessments on time, widening the achievement gap.

3. **Potential Solutions:**
- **Infrastructure Investment:** Governments investing in rural fiber-optic or satellite broadband initiatives.
- **Financial Support & Subsidies:** Providing free/subsidized devices and internet vouchers to low-income families.
- **Community Resources:** Establishing local digital hubs, mobile classrooms, or allowing school libraries to remain open after hours for internet access.
- **Alternative Delivery Methods:** Schools providing pre-loaded USB drives or offline learning packs for students with zero connectivity.

This question is marked using a levels-of-response marking grid (8 marks total):

**Level 1 (1–3 marks):**
- Demonstrates basic knowledge of the digital divide.
- Identifies one or two factors or impacts (e.g., 'some people are poor and cannot buy computers') but lacks depth or explanation.
- Information is presented with little structure and lacks appropriate ICT terminology.

**Level 2 (4–6 marks):**
- Demonstrates a good understanding of the digital divide.
- Explains at least two factors (geographical/economic/physical) and links them directly to their impact on online learning.
- Suggests at least one realistic solution to bridge the divide.
- The response is structured, mostly clear, and uses some appropriate ICT terminology.

**Level 3 (7–8 marks):**
- Demonstrates a comprehensive and detailed understanding of the digital divide.
- Thoroughly discusses geographical, economic, and physical/social factors, with a clear, balanced analysis of their impacts on student participation.
- Recommends and justifies multiple practical, well-thought-out solutions.
- The response is coherent, logically structured, and uses precise ICT terminology throughout.

Haptic feedback is a tactile feedback technology which recreates the sense of touch by applying forces, vibrations, or motions to the user. A games controller or force-feedback steering wheel are common output devices that use internal motors to vibrate and provide this physical feedback to the player during key events in a game.

1.75 marks for any valid output device that provides haptic/tactile feedback. Accept: Games controller / gamepad (with vibration), Force feedback steering wheel / joystick, Haptic vest / suit, VR controllers (with vibration). Reject: Speakers / Headphones (auditory), Monitor / Screen (visual).

An open-source software license allows users to view, modify, and distribute the underlying source code of the program. This is in contrast to proprietary (closed source) software, where the source code is kept private by the creator.

1.75 marks for identifying open source licensing. Accept: Open source (license), GNU General Public License (GPL), FOSS. Reject: Shareware, Freeware (since freeware provides the executable for free but usually does not provide the source code).

A MAC address is a unique hardware identifier assigned to a Network Interface Card (NIC) by the manufacturer. It is used to direct data packets to the correct physical device within a local area network (LAN).

1.75 marks for stating the purpose of identifying a device physically/locally. Accept: Uniquely identifies a device/NIC on a local network, Used for routing data at the physical/data link layer to a specific device. Reject: Identifies a device on the internet (this is an IP address function), Connects the computer to the internet.

Cloud-based collaborative suites allow multiple users to edit the same file in real-time. Examples include Google Docs, Microsoft Office Online (Word Online), and other cloud-hosted editors.

1.75 marks for identifying an appropriate online collaborative tool or specific platform. Accept: Cloud-based word processor / spreadsheet / presentation software, Google Docs / Google Sheets / Google Slides, Microsoft Word Online / Office 365, Shared online document / Real-time collaborative editor. Reject: Email (does not allow simultaneous editing of a single document), Offline Word processor.

A MAC address is a unique identifier assigned to a network interface card (NIC) by the manufacturer. Because it is hardcoded, it remains unchanged and represents the physical identity of the device. When data is sent across a LAN, switches read the destination MAC address to ensure the data is forwarded directly to the correct physical device rather than being broadcast to the entire network.

Award 1 mark for identifying that a MAC address uniquely identifies a physical device or Network Interface Card (NIC). Award 1 mark for explaining that it is static, unique, or hardcoded by the manufacturer. Award 1 mark for explaining that network switches use it to route or direct data packets to the correct destination device.

By choosing an open-source licence, the development team makes the underlying source code public. This allows external developers worldwide to inspect, modify, and improve the software. As a result, security vulnerabilities are discovered and patched faster, and new features can be integrated through community contributions without increasing the team's internal development costs.

Award 1 mark for identifying that open-source software makes the source code publicly viewable, editable, or shareable. Award 1 mark for explaining that this enables external developers to contribute, collaborate, or test the software. Award 1 mark for explaining the benefit, such as rapid bug fixing, community-driven feature additions, or cost reduction.

Indicative Content: 1. Accessibility and Reach: Public video sharing platforms are designed for global access across all devices and operating systems without complex configuration. Private servers would require external users (like parents or the public) to use VPNs or specialized login credentials, creating barriers to public outreach. 2. Cost and Infrastructure: Videos require massive amounts of storage space and bandwidth. Using a public platform eliminates the need for the academy to invest in high-capacity storage servers, backup systems, and specialized IT support. 3. Bandwidth and Performance: A local school network has limited upload bandwidth. If multiple users attempt to stream high-definition videos simultaneously from a local server, it will cause severe buffering and slow down other vital school network operations. Public platforms utilize global Content Delivery Networks (CDNs) to stream videos seamlessly. 4. Built-in Features: Public platforms offer automated video optimization (transcoding into various resolutions), closed captioning, playlists, and viewer analytics, which would require expensive custom software to replicate on a private server. 5. Counter-arguments and Mitigation: Public platforms may show distracting advertisements or inappropriate recommended content. However, the academy can mitigate this by embedding the videos directly onto the school website, using unlisted settings, or choosing ad-free educational subscription tiers.

Level 1 (1-3 marks): The response identifies basic advantages of public video platforms or disadvantages of local servers (e.g., public platforms are free, local servers have limited space). The points are descriptive and lack deep analysis or connection to the scenario. Level 2 (4-6 marks): The response compares both options with some analysis. It explains how technical factors like bandwidth, accessibility, and cost affect the academy's goals of peer learning and public outreach. The argument is structured but may lack a fully balanced justification or clear conclusion. Level 3 (7-8 marks): The response provides a highly detailed, balanced, and fully justified argument. It thoroughly analyzes technical, financial, and administrative impacts for both options in relation to the scenario. It reaches a logical, well-supported conclusion that addresses both benefits and how potential drawbacks of public platforms can be mitigated.