• All nodes ‘listen’ for traffic to sense when the network is idle.
• When a node wishes to transmit, it transmits a ‘request to send’ frame’ (RTS)
• The intended receiving device will transmit a ‘clear to send’ (CTS) frame if it is available.
• All other nodes ‘sense’ the network is busy and wait a random amount of time before trying to transmit

• Is the protection of programs and data in computers and communications systems against unauthorized modification, access or disclosure
•  

• URL is clicked/typed into a web browser address bar. The page is requested (by the web browser) so HTML and files are fetched from a web server and the browser collates the page, which is then displayed on the monitor.
• OR
  URL is clicked/typed into a web browser address bar (1). The browser locates the IP address either in cache or using a DNS server and the browser sends a request to the web server with that IP address web server uses HTTP to send back the requested web page and the browser displays the content of the page .

method of transmission e.g

• blue tooth
• radio
• optical
• satellite
• infra-red
• microwave

device e.g.

• 3G (WAP) mobile phones/mobile phones/cell phone/remote
• key pad/remote control/keyboard
• infra-red mouse
• multimedia mobile handsets/notebooks
• GPRS (general packet radio service) mobiles
• WLAN(or WiFi) hotspots sited in public areas - e.g. coffee
• shops, railway stations, airports, motorway services
• linked printers
• PDA's (personal digital assistants)
• GPS

• colour codes // colour in HTML/CSS
• error messages
• locations in memory
• memory dump // debugging 
• IP(v6) address
• ASCII // Unicode
• assembly language
• URL.

• Protection against Password-related Vulnerabilities: Traditional password-based authentication methods are vulnerable to various risks, such as weak passwords, password sharing, or password theft.
• Stronger Access Control: Biometric readers add an additional layer of access control to laptops. Even if someone gains physical possession of the laptop, they would still need the authorized user's biometric data to unlock it and access the data. This helps prevent unauthorized individuals from accessing sensitive information stored on the laptop,
• Audit Trail and Accountability: Biometric authentication systems often come with built-in logging and auditing capabilities. This means that each time someone accesses the laptop using their biometric data, it can be recorded and associated with a specific user. This creates an audit trail, allowing organizations to track and monitor access to laptops and establish accountability in case of any security incidents or breaches.

Multitasking - the  capability of an operating system to enable users to run two or more programs at once on a single computer

Real time processing - data processing system in which the time interval required to process and respond to inputs is so small that the response itself is useful for controlling the physical activity of a process

Time-sharing processing  - a processing mode in which the central processor serves two or more users with different processing requirements (tasks)

On-line processing - is that type of processing where the result of data processing transaction is available immediately

• Recommendation on whether to continue or abandon the project
• Methods used to collect data
• benefits and limitations expected
• the technology required to develop and maintain the project
• Installation and running cost
• Time limit

May not have space for cables to be installed

Employees and visitors can move around the building without disconnecting

Adding new users just means giving out the SSID and password

• more efficient than a human
• more accurate than a human
• can lift larger and heavier equipment than a human
• can replace humans working in a dangerous environment
• reduces running costs, such as wages and overheads
• can produce consistent results/output
• can work 24 hours a day // do not need to take breaks.

1. Speeds up coding since converting a pseudocode into a programming language is usually faster and easier
2. Acts as documentation
3. Simplifies debugging since logical errors can be identified and corrected early in design stage
4. Language independent since it is not tied to any specific language so can be translated into different languages
5. It uses simple english-like statements

• the computer appears to “freeze”/”hang”
• computer won’t respond
• failure of hardware (stops computer normal functioning)
• failure of software (stops computer normal functioning)

• Serial is the transmission of data one bit at a time/through one wire
• Parallel is the transmission of data more than one bit at a time/many wires
• Simplex is the transmission of data in one direction only
• Duplex is the transmission of data in both directions simultaneously

Ochieng manages a network for an organisation.
(a) Two computers are assigned the same IP address.
Explain why Ochieng must change the IP address of one of the computers.

• Devices must have a unique IP address because otherwise, a switch would not know which of the two was the correct device to send packets to

(b) Identify the network topology that requires a server.

• Star topology

HTTPS/HTTP: this is a protocol that is used to send data to web pages across the Internet

Uniform Resource Locator (URL):   a text-based version of a web address

Internet Service provider /ISP  - his is the company that provides a user with a connection to the Internet

browser - Software/application that allows users to view web pages / render HTML -

cookie - a text file (stored by a web browser) that contains data about a user’s browsing habits/details/preferences

• Single-mode fibre consists of a narrow core in which all light pulses travel at the same speed and arrive roughly at the same time at the destination.
• Supports higher bandwidth with less signal loss over a greater distance
• Multi-mode Multi-mode fibre consists of a larger core in which multiple light pulses can travel down the core.
• Supports a smaller bandwidth and signals attenuate at a shorter distance than single mode fibre.

– multiple choice/yes-no answers
– easy to understand interface e.g. use of icons/drop down menus etc.
– output shown as % probabilities of fault

1. MAN
2. WAN
3. PAN
4. LAN

• It is a feature used to prevent unwanted changes to be made on the data contained in a sheet by limiting the ability to make changes