Paper 1: Data Transmission Flashcards
Serial Data Transmission
Data is sent one bit at a time over a single wire. Useful for long distances where fewer wires are preferred (e.g., USB).
Parallel Data Transmission
Multiple bits of data are sent simultaneously over several parallel wires. Generally faster for short distances (e.g., within a computer).
Simplex Transmission
Data transmission in only one direction (e.g., a radio broadcast).
Half-Duplex Transmission
Data transmission in both directions, but only one direction at a time (e.g., a walkie-talkie).
Full-Duplex Transmission
Data transmission in both directions simultaneously (e.g., a phone call).
Packet Switching
A method of transmitting data by dividing it into small units called packets, which are then sent independently over a network and reassembled at the destination. Makes efficient use of network resources.
Parity Check
A simple method of error detection where an extra bit (parity bit) is added to a group of bits to indicate whether the number of 1s is even or odd.
Check Digit
An extra digit added to a code (like an ISBN or barcode) to help detect errors during data entry or transmission.
Checksum
A more sophisticated error detection method where a numerical value is calculated from a block of data and transmitted with it. The receiver recalculates the checksum and compares it to the received one.
Encryption
The process of converting data into a secret code (ciphertext) to prevent unauthorized access.
Symmetric Encryption
An encryption method that uses the same key for both encrypting and decrypting data.
Asymmetric Encryption
An encryption method that uses two different keys: a public key for encryption and a private key for decryption. The public key can be shared, but the private key must be kept secret.
Internet
A global network of interconnected computer networks that use the Internet Protocol Suite (TCP/IP) to communicate.
World Wide Web (WWW)
A system of interlinked hypertext documents (web pages) accessed via the Internet. It’s one of the services that runs on the Internet.
URL (Uniform Resource Locator)
The address of a resource on the internet (like a web page). It tells the browser how and where to find the resource.
HTTP (Hypertext Transfer Protocol)
The protocol used for transferring files (like web pages, images, etc.) on the World Wide Web.
HTTPS (Hypertext Transfer Protocol Secure)
A secure version of HTTP that encrypts the communication between the web browser and the web server, protecting sensitive data.
HTML (Hypertext Markup Language)
The standard markup language for creating web pages. It defines the structure and content of a web page.
CSS (Cascading Style Sheets)
A style sheet language used for describing the look and formatting of a document written in HTML. It controls the visual presentation of a web page.
IP Address (Internet Protocol Address)
A unique numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication.
MAC Address (Media Access Control Address)
A unique hardware address assigned to a network interface controller (NIC) of a device. It’s used for communication within a local network.
Cookie (Internet)
A small piece of data sent from a website and stored on the user’s computer by the web browser. It can be used to remember information about the user or their browsing activity.
Malware
Software that is intended to damage or disable computers and computer systems. Examples include viruses, worms, and spyware.
Phishing
A type of online fraud where criminals try to trick you into giving them personal information (like passwords or credit card details) by pretending to be a legitimate organization.
Denial-of-Service (DoS) Attack
An attack that aims to make a computer resource unavailable to its intended users, often by overwhelming it with traffic.
Firewall (Software/Hardware)
A security system that monitors and controls incoming and outgoing network traffic based on pre-defined security rules. It acts as a barrier between a trusted internal network and an untrusted external network (like the internet).
Antivirus Software
Software designed to detect, prevent, and remove malware from a computer system.
Password
A secret sequence of characters used to verify the identity of a user and grant access to a system or resource.
Authentication (Methods)
The process of verifying the identity of a user. Examples include passwords, PINs, biometric scans (fingerprint, facial recognition), and two-step verification (using two different methods).
