Information and Communication Technology (9-1) 0983 | Paper 1 Mock 21 | Theory

(a) The difference between an LED display and an OLED display:

• An LED display uses a liquid crystal layer with LED backlighting behind the entire screen to illuminate the pixels. The backlight is always on, which means the screen cannot achieve true black. [1]
• An OLED display uses organic compounds that emit their own light when an electric current is applied. Each pixel produces its own light individually, so there is no need for a separate backlight layer. [1]

(b) Two advantages of OLED technology compared to LED:

• OLED screens can display true black by completely turning off individual pixels (since there is no backlight bleeding through). This produces higher contrast ratios and more vivid, lifelike colours. [1]
• OLED screens can be made thinner and more flexible than LED screens because they do not require a backlight layer, enabling curved or foldable display designs. [1]

(c) Two devices that commonly use OLED screens:

• High-end smartphones [1]
• Modern smartwatches [1]

(a) Data verification is the process of checking that data entered into the database is an accurate copy of the original source document. [1] This matters because even small transcription mistakes, such as a misspelled surname or a wrong digit in a phone number, can lead to failed communications or incorrect records. By comparing the entered data against the original form or document, the club ensures the database reflects reality. [1]

(b) Two methods of data verification the club could use:

1. Double entry: the data is entered twice, either by the same operator or by two different operators. The system then automatically compares both entries and highlights any differences, prompting the operator to check and correct them. [1]
2. Visual check (proofreading): after entering the data, the operator reads through it on screen and compares each field against the original source document (for example, a printed membership application form) to spot and correct any discrepancies. [1]

(c) Data validation checks whether entered data is reasonable and conforms to predefined rules, such as format checks, range checks, length checks or type checks. [1] However, an incorrectly entered address could still pass every validation rule: it could be the right length, contain valid characters, follow the correct format and fall within an acceptable range. Because the address is plausible even though it is wrong, validation accepts it. Only verification, which compares the entry against the original source, would catch this kind of error. [1]

(a) The difference between the World Wide Web and the internet:

• The internet is the global physical network of interconnected computers, servers, routers and cables that provides the infrastructure for digital communication. [1]
• The World Wide Web (WWW) is a collection of web pages, websites and resources that are accessed over the internet using web browsers and the HTTP/HTTPS protocol. [1] The web is a service that runs on the internet, but the internet also supports other services such as email and file transfer.

(b) One advantage and one disadvantage of a bus network topology (as shown in the diagram):

• Advantage: It is easy and inexpensive to set up because only a single main cable (the bus) is needed, and devices connect to it with short drop cables. [1]
• Disadvantage: If the main cable (bus) fails at any point, the entire network goes down because all devices share the same communication channel. [1]

(c) Two ways websites use multimedia to communicate information:

1. Websites embed video to demonstrate products, explain concepts visually or show news footage, making content more engaging than text alone. [1]
2. Websites include audio content such as podcasts, interviews or music to provide information or entertainment that users can listen to while doing other tasks. [1]

(a) More RAM allows the computer to hold more programs and data in active memory at the same time. [1] When RAM is insufficient, the operating system must swap data between RAM and the much slower storage drive (a process called virtual memory or paging), which significantly slows the computer down. [1]

(b) The difference between RAM and an SSD:

• RAM is temporary (volatile) memory used to store data and programs that are currently being used by the processor. Its contents are lost when the computer is turned off. [1]
• An SSD (Solid State Drive) is permanent (non-volatile) storage used to store files, programs and the operating system. Data on the SSD is retained when the computer is turned off. [1]

(c) A "3.2 GHz processor" means the processor's clock runs at 3.2 gigahertz, which is 3.2 billion clock cycles per second. [1] A higher clock speed means the processor can execute more instructions in a given time period, making the computer faster at running programs and completing tasks. [1]

(a) Two methods of data transmission shown in the diagram:

• Serial transmission sends data one bit at a time along a single channel. The bits travel sequentially one after another. This method is used for long-distance communication because it is simpler and cheaper to implement over long cables. [1]
• Parallel transmission sends multiple bits simultaneously along multiple channels (for example, 8 bits at once using 8 separate wires). This is faster but is used for short-distance communication within a device, because over longer distances the signals on different wires can arrive at slightly different times, causing errors. [1]

(b) Advantages of fibre optic cable compared to copper cable:

• Fibre optic cables transmit data using light signals at much higher speeds than the electrical signals used in copper cables, supporting greater bandwidth. [1]
• Fibre optic cables are not affected by electromagnetic interference and can carry data over longer distances without signal degradation, making them more reliable. [1]

(c) Two reasons a business might choose a client-server network over peer-to-peer:

• A client-server network has centralised file storage and management on a dedicated server, making it easier to perform backups and enforce security policies across the entire network. [1]
• User access rights and permissions can be managed centrally by the network administrator, ensuring consistent security rather than relying on each individual user to manage their own machine. [1]

(a) Two electrical safety hazards in a room with many computers:

• Overloading power sockets by plugging too many devices into a single outlet can cause overheating and potentially start a fire. [1]
• Damaged or frayed power cables with exposed wiring can cause electric shocks if touched, or can create a short circuit leading to fire. [1]

(b) Three precautions to reduce electrical safety risks:

• Use surge-protected power strips to prevent damage from power surges and to avoid overloading individual sockets. [1]
• Regularly inspect all cables and power leads for signs of damage and replace any that are worn or frayed before they become dangerous. [1]
• Ensure all electrical equipment is tested and certified by a qualified electrician at regular intervals (known as PAT testing). [1]

(c) Why trailing cables are a physical hazard:

Trailing cables across the floor create a trip hazard that could cause someone to fall and injure themselves, and could also pull equipment off the desk if snagged by a passing person. [1]

(a) The difference between a microprocessor and a microcontroller:

• A microprocessor is a standalone processing unit that requires external components such as memory and input/output interfaces to function. It must be connected to these components on a circuit board. [1]
• A microcontroller integrates the processor, memory and input/output interfaces onto a single chip, forming a complete system on one integrated circuit. [1]

(b) Two components typically built into a microcontroller but separate from a microprocessor:

• RAM (random access memory) for temporary data storage. [1]
• Input/output ports for connecting directly to sensors and actuators. [1]

(c) Two reasons why a microcontroller is more suitable for a simple embedded device like a toaster:

• A microcontroller is cheaper because all components are on one chip, reducing manufacturing costs for simple devices that only need to perform a single task. [1]
• A microcontroller uses less power than a microprocessor with separate components, making it suitable for small, low-power devices where energy efficiency matters. [1]

(a) Two advantages of using email for communicating across different time zones:

• Emails can be composed and sent at any time, and the recipient can read and respond when it is convenient in their own time zone. There is no need for both parties to be available simultaneously. [1]
• A written record of all communications is automatically kept in the email system, making it easy to refer back to previous discussions, decisions and instructions without relying on memory. [1]

(b) Two limitations of using email for team collaboration:

• Email is not suitable for real-time discussions, as there can be significant delays between sending a message and receiving a reply. Quick decisions that require immediate back-and-forth are slowed down. [1]
• Long email chains with many replies and forwarded messages can become confusing and difficult to follow. Important information can easily be buried in the thread, and different team members may be responding to different versions of the discussion. [1]

(c) Two alternative methods of online communication the team could use alongside email:

• Video conferencing (such as Zoom or Microsoft Teams) for real-time face-to-face meetings, allowing participants to see each other and share screens. [1]
• Instant messaging (such as Slack or Microsoft Teams chat) for quick, informal real-time text communication that is faster and more fluid than email for short exchanges. [1]

(a) Examples of input and output devices:

• Input device: Keyboard (or mouse, scanner). [1] An input device sends data into the computer for processing.
• Output device: Monitor (or printer, speakers). [1] An output device presents processed data from the computer to the user.

(b) The role of the CPU (Central Processing Unit):

1. The CPU fetches instructions from memory, decodes them to understand what operation is required, and then executes them. This is known as the fetch-decode-execute cycle. [1]
2. It performs all the processing in the computer, including arithmetic calculations, logical comparisons and data movement between components. [1]

(c) The difference between RAM and ROM:

• RAM (Random Access Memory) is volatile memory, meaning it loses all its contents when the power is switched off. It is used to hold the data and programs that are currently being used by the processor. [1]
• ROM (Read Only Memory) is non-volatile memory, meaning it retains its contents permanently even when the power is off. It stores the startup (boot) instructions that the computer needs to begin operating when first turned on. [1]

(a) The firewall sits between the internet and the company's internal network. It monitors all incoming and outgoing network traffic [1] and blocks unauthorised access by filtering data packets according to predefined security rules, while allowing legitimate traffic to pass through. [1]

(b) Two other security measures the company should implement are:

• Install anti-virus and anti-malware software on all computers to detect and remove malicious programs before they can cause damage. [1]
• Enforce strong passwords and user authentication policies so that only authorised personnel can access the network and its resources. [1]

(c) The company should use encryption when sending data over the internet because encryption converts data into an unreadable coded form during transmission. [1] If the data is intercepted by an attacker while travelling across the internet, they will not be able to read or make use of the information, protecting sensitive business and customer data. [1]

(d) One physical security measure is to keep the server in a locked, dedicated server room with access restricted to authorised IT staff only, controlled by key cards or biometric locks. [1] This prevents unauthorised individuals from physically accessing, tampering with, or stealing the server hardware and the data stored on it. [1]

(a) The ADC (analogue-to-digital converter) converts the analogue signal produced by the temperature sensor [1] into a digital value that the microprocessor can process. [1] Temperature is a continuous physical quantity, and the sensor produces an analogue electrical signal. Since the microprocessor can only work with digital data (binary numbers), the ADC performs this essential conversion.

(b) Feedback is used so the system can continuously monitor the actual temperature of the room. [1] By feeding the current temperature reading back to the microprocessor, the system can compare it against the desired temperature and automatically adjust the heater or fan output to maintain the correct temperature without human intervention. [1] Without feedback, the system would have no way of knowing whether its actions were having the intended effect.

(c) The heater/fan shown in the diagram is an actuator. [1] Its role is to physically change the environment by heating the air (when the temperature is too low) or cooling it with the fan (when the temperature is too high), in direct response to control signals from the microprocessor. [1]

(a) Three types of multimedia content for the charity's web page:

1. Video, such as footage showing the charity's work in action, testimonials from beneficiaries or a promotional appeal. [1]
2. Audio, such as an interview with a volunteer, a podcast episode about the charity's mission or a recorded speech from a fundraising event. [1]
3. Animation, such as an animated infographic that visually explains the charity's impact using moving graphics and statistics. [1]

(b)

• Advantage: Multimedia makes the page more engaging and emotionally impactful, helping to communicate the charity's message more effectively than text and static images alone. [1]
• Disadvantage: Multimedia files (especially video) are large and increase page loading times, which may deter visitors with slow internet connections from staying on the site. [1]

(c) To ensure disabled users can access the information, the charity should provide text-based alternatives such as captions (subtitles) for video content and written transcripts for audio content. [1] This allows users who are deaf or hard of hearing, or who use screen readers, to access the same information.